Socioeconomic disparities in sarcoma diagnosis, expert center access, and advocacy group awareness: a multicenter study in Southern Europe

Abstract

Background

Management of sarcoma in expert centers (SECs) improves outcomes, and patient advocacy groups provide information, support, and representation of patients’ needs; however, access to both remains uneven. We aimed to identify factors associated with patient referral and advocacy group awareness in Spain and Portugal, 2 universal healthcare systems with distinct sarcoma pathways.

Materials and Methods

Between April and December 2023, we conducted a survey-based study of adults with sarcoma under active treatment or follow-up across 9 Spanish hospitals (5 SECs) and one Portuguese hospital. Sociodemographic and clinical data, referral patterns, and advocacy group awareness/contact were analyzed.

Results

A total of 415 patients were included (Spain, n = 365; Portugal, n = 50). In Spain, lower income (odds ratio [OR] 2.38; 95% CI, 1.16-5.03) was associated with longer diagnostic delays. Rural residence (OR 3.48; 1.79-7.04) and longer diagnostic delays (OR 2.41; 1.26-4.66) were associated with referral to other hospitals. Cancer advocacy group awareness was lower among patients with lower income (OR 0.38; 0.17-0.81) and higher with longer diagnostic delays (OR 2.08; 1.05-4.25). Sarcoma-specific advocacy group awareness was generally low (20%) but higher with university education (OR 4.27; 1.56-12.35). Few patients contacted cancer (14%) or sarcoma-specific groups (7%); contact was more frequent with longer diagnostic delays (OR 2.27; 1.11-4.63) or symptomatic presentation (OR 2.50; 1.04-5.97). Compared with the Portuguese cohort, Spanish patients were referred less frequently and had greater awareness of advocacy groups.

Conclusion

Socioeconomic disparities affect sarcoma diagnosis, referral, and advocacy group engagement, even within universal healthcare systems. Equity-oriented care requires timely SEC referral and advocacy group visibility.

Implications for practice.

This multicenter study of 415 patients with sarcoma in Spain and Portugal identifies socioeconomic differences across several aspects of the sarcoma care pathway even within universal healthcare systems. Lower income was associated with longer reported diagnostic delays and lower awareness of cancer advocacy groups. Awareness of sarcoma-specific groups was low overall and higher among patients with university education. Longer diagnostic delays and symptomatic presentation were associated with advocacy-group contact. Clinicians and health systems should prioritize timely referral to sarcoma expert centers and signpost patients to advocacy resources, particularly those most socioeconomically vulnerable, to promote more equitable, patient-centered care.

Introduction

The RARECARE initiative defines rare tumors as cancers with an incidence ≤6 per 100,000 persons per year.¹ Although individually uncommon, their collective health burden is substantial, accounting for nearly one-quarter of all cancer diagnoses.^2,3 Moreover, patients with rare cancers tend to have poorer prognosis compared to their common counterparts (5-year relative survival 49% vs 63%).^3,4 This is likely driven by several factors: delayed or incorrect diagnosis, limited clinical expertise resulting in greater variability in care quality, challenges in drug development, and insufficient awareness among clinicians and patients regarding available treatments, care pathways, and supportive resources.^5–7

Among rare malignancies, sarcomas stand out as a paradigm. They represent only 1% of adult cancers despite comprising more than 100 entities,^8–10 of which 77 qualify as ultra-rare (incidence ≤1 per 1,000,000 persons per year) by the Connective Tissue Oncology Society definition.¹¹ Sarcoma outcomes remain poor in advanced disease, with an overall survival of approximately 18 months.^12,13 Their rarity limits accrual for adequately powered prospective trials, hindering the generation of robust evidence and impeding evidence-based decision-making. Consequently, most guideline recommendations rely on observational non-randomized studies or expert consensus (evidence levels III-IV).^14,15 As an additional layer of complexity, socioeconomic disparities in access to care and diagnostic pathways are documented worldwide; although greatest in low-income settings, they persist in high-income countries, with direct implications for cancer outcomes.^16–20 In Europe, lower educational attainment has been associated with higher incidence and mortality for nearly all cancer types,^21,22 with similar trends in the United States.^23–25 These inequities may be even more pronounced in sarcomas and other rare cancers,²⁶ but remain largely unknown.

In this context, multidisciplinary tumor boards (MDTB) play a central role in sarcoma management, guiding most diagnostic and therapeutic decisions.^18,27 Because MDTB are typically based in high-volume reference centers, well-structured referral networks at the national and European levels are essential to ensure timely access to expert care. In fact, their implementation and the management of sarcomas within reference centers have been associated with improved outcomes and guideline adherence.^28–32 Nevertheless, differences in healthcare organization between countries, even within universal healthcare coverage, can further attenuate or amplify disparities. For instance, in Southern Europe, Spain has a national referral network composed of 8 adult sarcoma expert centers (SECs), designated by the Spanish Health Ministry on the basis of specific high-volume and quality criteria,^33,34 alongside several active sarcoma advocacy groups. Unlike mandatory referral systems operating in other European countries,^29,31 referral to SECs in Spain remains voluntary and dependent on the referring physician or center.^33,34 By contrast, Portugal centralizes most of the cancer care within 5 national comprehensive centers but lacks dedicated sarcoma networks and sarcoma-focused advocacy groups. As healthcare and research increasingly shift toward patient-oriented models, patient advocacy groups are also becoming key stakeholders, especially in rare cancers.^35–37 Their contributions include providing psychological support to patients and families; offering information on disease natural course, quality of life and treatment options; and giving voice to patient needs, which can help shape and prioritize healthcare policies.^38–40 Increasing awareness among both patients and professionals of the role and resources offered by sarcoma advocacy groups therefore represents a clear unmet need and an important opportunity to improve sarcoma care.

In this study, we examined sociodemographic and geographic factors associated with disparities in sarcoma care pathways in Southern Europe. Specifically, we aimed to identify determinants of diagnostic inequities, referral patterns, advocacy-group awareness, and contact, assess patients’ perceptions of advocacy groups, and compare these patterns between Spain and Portugal, neighboring countries with contrasting cancer care and referral models.

Materials

Ethical considerations

The study was approved, where required, by the Institutional Review Boards of participating centers and conducted in accordance with applicable regulations, including the General Data Protection Regulation (EU 2016/679), Spanish Organic Law 3/2018, and the Declaration of Helsinki. Surveys were anonymous and contained no identifiable information. Participation was voluntary, without incentives. Patients were informed that their responses would be used for research purposes; therefore, completion of the survey was considered to imply informed consent.

Study design and patient population

This prospective study involved 9 Spanish cancer centers: 5 SECs (Vall d’Hebron University Hospital, Santa Creu i Sant Pau Hospital, Gregorio Marañón University Hospital, Clínico San Carlos University Hospital, and La Paz University Hospital), 4 non-SECs (Basurto University Hospital, Miguel Servet University Hospital, Ciudad Real General University Hospital, and A Coruña University Hospital Complex), and one Portuguese cancer center (Portuguese Oncology Institute of Porto, Francisco Gentil).

Eligible participants were adults with histologically confirmed sarcoma receiving active systemic treatment for localized or advanced disease or undergoing follow-up after radical-intent treatment between April and December 2023.

Data collection

Data were collected using a survey jointly developed by the Spanish Group of Sarcoma Research (GEIS) and sarcoma patient representatives. Survey materials were emailed to GEIS investigators, who received 3 reminders during the first 2 months. Investigators printed and offered the survey consecutively to eligible patients during routine visits; patients were not contacted electronically. The number of patients invited was not recorded. At study completion, the surveys were submitted to the coordinating center (Vall d’Hebron University Hospital). The same procedure was followed for the Portuguese cohort using a translated version of the survey. Sociodemographic information included age, sex, level of education (elementary, secondary, or university studies), province of residence (for Spanish population only) and type of living area (rural or urban), and personal income. Sex was self-reported by participants as male or female; gender identity was not separately assessed. Patients were categorized into low or high income based on self-reported income relative to the median individual annual gross salary in Spain in 2023, with those reporting below-median income classified as low income. Clinical data included age of diagnosis, the specific sarcoma subgroup (soft tissue sarcomas [STS], bone sarcomas, gastrointestinal stromal tumors [GIST], or others), disease presentation (asymptomatic, lump or symptomatic, with specification of symptoms), time from first symptom to diagnosis (if applicable), and information about center referral (either physician’s choice or self-requested transfer). Variables related to patient engagement with advocacy groups included awareness of cancer and sarcoma-specific advocacy groups, prior contact with these groups, patients’ opinions of their role, and the perceived benefit provided.

Statistical analysis

Qualitative variables were summarized using frequencies and percentages, while quantitative variables were reported as medians with interquartile ranges. Group comparisons were conducted using Pearson’s χ² test for categorical variables and the Wilcoxon rank-sum or Kruskal–Wallis tests for comparisons between 2 or more groups, respectively, for continuous variables.

Multivariable logistic regression models were fitted to assess associations between variables, expressed as odds ratios (ORs) with 95% CI. Within each multivariable logistic regression model, P-values were adjusted for multiple comparisons using the Benjamini–Hochberg false discovery rate correction. Statistical significance was defined as P ≤ .05. All statistical procedures were performed using R software (version 4.4.2). No formal sample size or power calculation was performed. In both countries, the sample comprised all eligible patients who returned the survey at participating centers during the study period; no target or maximum was set. The Spain–Portugal comparison was therefore considered exploratory.

Results

Spanish cohort

Baseline characteristics

From 125 institutions across 17 autonomous communities in Spain within the GEIS network, 9 institutions from 6 different autonomies submitted the surveys (see above in Material and Methods). This cohort included 365 patients (Table 1). The median age was 57 years, and 53% of patients were female. Most patients lived in urban areas (76%) and reported lower-than-average personal income (74%). Educational attainment was evenly distributed across elementary (32%), secondary (35%), and university levels (33%).

Table 1.

Characteristics of the Spanish and the Portuguese cohorts.

Characteristic—n (%)	Spain N = 365	Portugal N = 50	P-valuea
Age (y)—median (IQR)	57 (47-66)	59 (45-69)	.7
Female sex	192 (53)	23 (46)	.5
Region (Spanish Autonomous Communities)			N/A
Aragon	22 (6)	N/A
Catalonia	170 (47)	N/A
Madrid	97 (27)	N/A
Basque Country	45 (12)	N/A
Other	31 (8)	N/A
Living area			.056
Urban	279 (78)	32 (64)
Rural	81 (23)	18 (36)
Missing	5	0
Reported income			.092
Low	257 (74)	31 (62)
High	88 (26)	19 (38)
Missing	20	0
Education			<.001
Elementary	112 (32)	32 (64)
Secondary	122 (35)	10 (20)
University	115 (33)	8 (16)
Missing	16	0
Sarcoma type			<.001
Soft tissue	195 (54)	18 (36)
Bone	39 (11)	7 (14)
GIST	72 (20)	23 (46)
Other	20 (5.5)	2 (4)
Unknown	37(10)	0 (0)
Missing	2	0
Year of sarcoma diagnosis			.001
<2010	25 (7)	12 (24)
2010-2019	195 (58)	26 (52)
≥2020	117 (35)	12 (24)
Missing	28	0
Symptomatic disease at diagnosis?			.2
No	53 (15)	6 (12)
Palpable mass only	143 (39)	14 (28)
Yes (pain, hemorrhage, etc.)	167 (46)	30 (60)
Missing	2	0
Time to diagnosis (m)			.003
Mean (SD)	5.8 (12.2)	2.4 (2.7)
Median (IQR)	2 (1-6)	2 (0.3-3)
Missing	25	0
Center of treatment			N/A
SECs	257 (70)	N/A
Non-SECs	108 (30)	N/A
Same hospital diagnosis and treatment?			<.001
Yes	193 (54)	10 (20)
Yes, but requested second opinion	8 (2)	0 (0)
No, referred to other hospital	123 (34)	40 (80)
No, requested a change	35 (10)	0 (0)
Missing	6	0

Abbreviations: GIST, gastrointestinal stromal tumor; IQR, interquartile range; m, months; N/A, not applicable; SEC, Sarcoma Expert Center; y, years.

^aPearson’s chi-squared test; Wilcoxon rank sum test.

STS was the most common sarcoma group (54%), followed by GIST (20%) and bone sarcomas (11%). Notably, 37 patients (10%) were unaware of their specific sarcoma subgroup. More than half of the patients (58%) had been diagnosed between 2010 and 2020, while 117 (35%) were diagnosed after 2020. The disease was most frequently diagnosed at a symptomatic stage (46%) with pain or hemorrhage, while a palpable mass was the initial presentation in 143 patients (39%).

Time to sarcoma diagnosis

Median time from symptom onset to diagnosis was 2 months (IQR: 1-6). Female patients more frequently reported delays ≥6 months (33% vs 19% of males; P = .013; Table S1), although this association did not remain significant in multivariate analysis. By sarcoma subgroup, GIST was associated with shorter diagnostic delays: 78% of patients with GIST were diagnosed in less than 3 months compared with 48%, 34%, and 26% in STS, bone sarcomas and other subgroups of sarcomas, respectively (P < .001; Table S1).

In the multivariate analysis (Figure 1A), lower income was independently associated with longer diagnostic delays: 52% of patients with lower income reported a delay ≥3 months compared with 40% of patients with higher income (OR 2.38, 95% CI 1.16-5.03; P = .020). Patients referred to other centers also experienced longer diagnostic delays: 58% of referred patients had a delay ≥3 months vs 45% of non-referred patients (OR 2.0; 95% CI 1.14-3.56; P = .016). Patients diagnosed more recently reported longer diagnostic delays across all periods compared with those diagnosed before 2010 (Figure 1A). No differences were observed by education level or residence area.

Figure 1.

Multivariable analyses of factors associated with diagnostic delay and referral to specialist care. (A) Variables associated with a diagnostic delay ≥3 months. (B) Variables associated with referral to another hospital for treatment (including physician-initiated referral and patient-requested transfer). Abbreviations: m, months; SEC, Sarcoma Expert Center.

Treatment center and pattern of referral

Overall, 257 of 365 patients (70%) were treated at SECs, while the remaining 108 patients (30%) were managed at non-SECs. Regardless, most patients (201; 55%) received treatment at the same hospital where the diagnosis was established, while 123 (34%) were referred to a different institution for treatment. Additionally, 35 patients (10%) self-requested transfer to another center.

Patients managed at non-SECs had lower education levels (university studies: 23% vs 37% in SECs; P = .015) and were more likely to reside in rural areas (33% vs 18%; P = .004). Patients in non-SECs were also more frequently diagnosed in a symptomatic disease stage (55% vs 42%; P = .044). Significant differences were observed regarding sarcoma subgroups treated in each type of center (P = .001), with higher percentage of GIST in non-SECs (32% vs 15%) and higher rates of bone sarcomas in SECs (13% vs 6%). Univariate analyses comparing patients managed at non-SECs vs SECs are presented in Table S2. With regard to patient referral, patients who were transferred to other hospitals for treatment were significantly younger than those who were not transferred, regardless of whether they were referred by their attending physicians or actively requested the transfer themselves (median age: 60 years for patients not referred/transferred vs 53 years for referred patients vs 52 years for patients who requested a change; P = .005 across groups; Table S3).

In the multivariate analysis (Figure 1B), patients residing in rural areas were significantly more likely to be referred to other hospitals for treatment (referral rates: 55.7% vs 39.9% in urban areas; OR 3.48; 95% CI 1.79-7.04; P < .001). Furthermore, patients with a diagnostic delay ≥6 months were also more likely to be referred for treatment (referral rates: 42% vs 31.9% in those with <6 months of diagnostic delay; OR 2.41; 95% CI 1.26-4.66; P = .008). Consistent with this, patients managed at SECs were more likely to have been referred from other centers (39% vs 22%) or actively requested a center transfer as compared to those treated at non-SECs (13% vs 2.8%; OR for referral/transfer: 4.65; 95% CI 2.47-9.15; P < .001).

Patient advocacy groups awareness and contact

While most patients (66%) were aware of the existence of cancer patient advocacy groups, only 20% were aware of sarcoma-specific advocacy groups. Contact rates were low overall: 14% for cancer advocacy groups, and 7% for sarcoma-specific ones.

Awareness differed significantly by region (Figures 2A and 3), being highest in Aragón (87% for cancer and 59% for sarcoma-specific groups) and lowest in Galicia (33%) and Castilla-La Mancha (9%), respectively (P = .026 and P < .001). Contact rates paralleled awareness, ranging from 36% in Aragón to 0% in Galicia (P = .003). Awareness also varied by subgroup (Figures 2B and 3): patients with GIST showed the highest sarcoma-specific awareness (37%), and those with STS or an unknown subgroup the lowest (16% and 11%; P = .003).

Figure 2.

Multivariable analyses of factors associated with patient engagement with patient advocacy groups. Variables associated with: (A) awareness of cancer advocacy groups; (B) awareness of sarcoma-specific advocacy groups; (C) contact with advocacy groups, including cancer and sarcoma-specific groups; and (D) favorable perceptions of sarcoma-specific advocacy groups (analysis of favorable perceptions of cancer advocacy groups is not shown because no significant associations were found). Abbreviations: m, months; SEC, Sarcoma Expert Center.

Figure 3.

Percentage of patients aware of sarcoma-specific patient advocacy groups by Spanish autonomous community (A) and sarcoma subtype (B). Abbreviations: GIST, gastrointestinal stromal tumor.

Patients who were aware of or had contacted advocacy groups were significantly younger than their counterparts (eg, for cancer advocacy groups, median age of 54 years in aware patients vs 57 years in unaware patients, P < .001; median age of 53 years in patients with previous contact vs 58 years among those without previous contact; P = .019). As expected, patients who were aware of the existence of cancer advocacy groups had higher contact with these associations (contact rate: 19% vs 4%; P < .001). Univariate analyses of variables associated with awareness of cancer advocacy groups, sarcoma-specific advocacy groups and contact with these associations are presented in Tables S4, S5, and S6, respectively.

In the multivariate analyses of factors associated with patients’ awareness of cancer advocacy groups (Figure 2A), lower income was independently associated with lower awareness of advocacy groups (61.1% and 79.5% in low vs high income, respectively; OR for awareness: 0.38; 95% CI 0.17-0.81: P = .021). On the contrary, longer diagnostic delays were associated with higher awareness of advocacy groups (awareness rates: 67.7% in patients with a diagnostic delay ≥6 months vs 57.4% in those with a diagnosis <3 months; OR for awareness: 2.08; 95% CI 1.05-4.25; P = .04). With regard to awareness of the existence of sarcoma-specific advocacy groups (Figure 2B), higher education was associated with higher awareness (33% in patients with university studies vs 12% in elementary studies; OR for awareness: 4.27; 95% CI, 1.56-12.35; P = .006). Interestingly, awareness was also significantly higher among patients treated at non-SECs vs SECs (27% vs 18%; OR for awareness: 2.47; 95% CI 1.24-4.99; P = .011). Regarding previous contact with patient advocacy groups (Figure 2C), factors independently associated included longer diagnostic delays (contact rates of 17.2% and 10.4% in patients with a diagnostic delay ≥6 months vs those with a diagnosis <3 months; OR: 2.27; 95% CI 1.11-4.63; P = .024) and symptomatic disease at diagnosis (24.5% vs 16.1% in those with asymptomatic presentation; OR: 2.50; 95% CI 1.04-5.97; P = .038).

Patients’ opinion on advocacy groups

Most patients regarded patient advocacy groups as necessary or indispensable: 81% for cancer advocacy groups and 73% for sarcoma advocacy groups. Regarding the potential role of these advocacy groups, patients most frequently believed they could provide information about the disease (76%), assurance and support (60%), psychological assistance (56%), treatment information (52%), and information regarding ongoing clinical trials (44%).

In the multivariate analysis of factors influencing patients’ opinions on sarcoma-specific advocacy groups (Figure 2D), patients who were referred to other hospitals for treatment had more favorable perceptions of sarcoma-specific advocacy groups compared to those that were never referred (rates of positive opinions: 89% vs 77% in non-referred patients; OR 2.67; 95% CI 1.30-5.77; P = .01). Additionally, patients who had previously contacted sarcoma-specific advocacy groups showed a non-significant trend toward more favorable opinions compared with those who had not interacted with them (favorable opinion rates: 95.7% vs 78.8%; OR 7.44; 95% CI 1.31-142.46; P = .065). No independent associations were observed with perceptions of general cancer advocacy groups. Univariate analyses of factors associated with favorable perceptions on cancer and sarcoma-specific advocacy groups are presented in Tables S7 and S8, respectively.

Comparison with the Portuguese cohort

To explore the impact of healthcare system organization, we compared these results with a cohort of patients with sarcoma from the Portuguese Oncology Institute of Porto, Francisco Gentil, Portugal (n = 50, Table 1). Both cohorts were similar with respect to sex distribution, median age, income category, rural vs urban residence, and symptomatic presentation at diagnosis. However, the cohorts differed significantly in educational attainment, which was markedly higher in the Spanish cohort: 33% had university studies compared to 16% in Portugal; 64% of Portuguese patients had only elementary studies compared to 32% in Spain (OR for university studies, Spanish vs Portuguese cohort: 3.37; 95% CI 1.26-9.82; P = .019; Figure 4). The distribution of sarcoma subgroups also differed substantially, with a higher prevalence of STS in the Spanish cohort (54% vs 36%), while the Portuguese cohort had a higher proportion of GIST (46% vs 20%; P < .001).

Figure 4.

Multivariable analysis comparing the Spanish and Portuguese cohorts. Abbreviation: m, months.

Spanish patients reported longer diagnostic delays than Portuguese patients (mean time to diagnosis: 5.8 vs 2.4 months; P = .003). The median year of sarcoma diagnosis was more recent in the Spanish cohort than in the Portuguese cohort (2017 vs 2014; P = .001; OR for year of diagnosis ≥2020 vs <2010: 4.04; 95% CI 1.27-13.30; P = .019; Figure 4). Regarding referral patterns, most Portuguese patients were transferred to another hospital for treatment (80%), a significantly higher rate than in Spain (34%; OR for referral, Spain vs Portugal: 0.21; 95% CI 0.08-0.46; P < .001; Figure 4). This finding is consistent with Portugal’s more centralized model, in which cancer care is concentrated in fewer national comprehensive centers, leading to higher referral rates.

Notably, Spanish patients had markedly higher awareness of both cancer advocacy groups (66% vs 16% in Portugal) and sarcoma-specific advocacy groups (20% vs 4%; OR for advocacy group awareness, Spain vs Portugal: 8.58; 95% CI 3.57-23.35; P < .001; Figure 4). This difference is consistent with the advocacy landscape in Portugal, where sarcoma-specific organizations are absent and the overall culture of patient advocacy is less established, which likely contributes to the higher proportion of neutral or negative opinions regarding patient advocacy groups reported by Portuguese patients (regarded as unnecessary/irrelevant in 20% vs 8% in Spain; P < .001). Univariate analyses comparing these 2 cohorts are presented in Table S9.

Discussion

Despite universal healthcare coverage in both Spain and Portugal, this study reveals meaningful socioeconomic disparities across care pathways of patients with sarcoma. That such inequities persist within universal systems suggests they may be even more pronounced in countries without guaranteed coverage. We found that lower-income patients experienced significantly longer diagnostic delays, compounding the preexisting burden of economic and geographic disadvantage. Although referral to larger institutions and specialist centers is common, particularly for patients in rural areas, the logistical, financial, and psychosocial demands of this process may place considerable strain on patients during an already vulnerable period. Additionally, female patients reported longer diagnostic delays than male patients, a striking disparity that may reflect cultural norms, differences in how symptoms are interpreted, or gender-related barriers within the healthcare pathway.^41,42

Patients managed at non-SECs were more frequently diagnosed at a symptomatic stage compared to SECs, and those referred to other hospitals experienced significantly longer diagnostic delays. Referral should not be viewed as an adverse outcome in itself. In centralized systems such as Portugal’s, transfer to a high-volume center is the usual pathway to specialist multidisciplinary care. In Spain, however, the absence of a mandatory referral pathway means that access to SECs depends on decisions by referring physicians, creating the potential for uneven or delayed access to specialist care when referral is not planned from the outset. In our cohort, referred patients were more likely to live in rural areas and reported longer diagnostic delays. Therefore, the relevant concern is not referral itself, but whether patients reach expert care equitably and promptly, and the logistical and personal burden involved.

Previous analyses from NETSARC and GEIS have shown that care in SECs leads to better survival outcomes and greater adherence to clinical practice guidelines.^29–31 Thus, our findings align with this evidence, indicating that these disparities begin early in the course of the disease, underscoring the need for timely referral to SECs. Furthermore, patients treated at SECs in our cohort were more likely to have sarcoma subtypes requiring multidisciplinary management, such as bone sarcomas, whereas patients with GISTs were more frequently managed outside SECs, possibly reflecting a more standardized therapeutic approach driven by the availability of tyrosine kinase inhibitors. Patients treated at SECs also more often had higher educational levels and lived in urban areas, suggesting that access to specialized sarcoma care is influenced not only by clinical factors but also by sociodemographic characteristics and geographic proximity to SECs.

Despite high awareness of cancer advocacy groups, awareness of sarcoma-specific groups and overall contact rates remained low. Patients’ awareness was associated with socioeconomic factors, being higher among younger patients and those with greater income and educational level. These findings highlight the need for organized efforts to raise awareness of patient advocacy groups so that all individuals, regardless of socioeconomic background, can access these valuable resources. Advocacy groups play a crucial role in rare cancers, where support and reliable information are often scarce.^38,40 In this study, patients treated in non-SECs showed higher awareness of advocacy groups, possibly reflecting a greater need for information when specialized guidance is less readily available. Similarly, patients with longer diagnostic delays and those diagnosed at more advanced, symptomatic stages had significantly higher contact with these organizations, possibly as a response to feeling unsupported or to compensate for prolonged uncertainty before obtaining a diagnosis. Along similar lines, patients referred to other hospitals held more favorable perceptions of advocacy groups, suggesting their value may be more readily recognized by those navigating complex care pathways. Moreover, the more positive views reported by patients who had previously interacted with these organizations suggest that direct experience may further reinforce recognition of their value. Although the direction of these associations cannot be determined from a cross-sectional design, together these findings highlight the potential role of patient advocacy groups in bridging gaps in sarcoma care. Given the disparities observed across European countries, including in our study, the evidence supports strengthening efforts to raise awareness of these groups to enhance patient engagement, promote greater involvement in care, and contribute toward a more patient-centered model of cancer management.

This is the first study, to our knowledge, to explore advocacy group awareness and engagement in patients with sarcoma. It is nationwide and multicenter, includes both expert and non-expert centers, and provides a comparison with a cohort from another healthcare system. It also provides a landscape of interest in Southern Europe regarding sarcoma patient-centered management in multidisciplinary networks, which is the current model pursued by bodies such as EURACAN and the European Commission.

Despite these valuable insights, several limitations must be acknowledged. The study is cross-sectional; therefore, the temporal or causal relationship between variables cannot be established. It is also survey-based and relies on self-reported data, which may be affected by recall, interpretation, and desirability biases. For instance, the association between more recent diagnosis and longer reported diagnostic delays, observed in both cohorts, likely reflects recall bias, as patients diagnosed earlier may have less accurate recollection of symptom onset. Despite offering the survey to consecutive eligible patients, sampling biases may still be present, as only patients willing to respond from centers willing to participate were included. Additionally, the few centers participating in this study may be more receptive to patient referral and advocacy engagement, potentially overrepresenting favorable features. Although treatment status at survey completion was not recorded, patients under surveillance may be overrepresented because long-term follow-up inherently selects survivors, potentially underrepresenting those with poorer prognosis. Some subgroup analyses were based on small sample sizes, resulting in imprecise estimates with wide confidence intervals that limit the reliability of those specific associations. Furthermore, the survey did not capture treatment received, clinical trial participation, or clinical outcomes, precluding assessment of whether engagement with patient advocacy groups influenced patient care. Lastly, the Portuguese cohort was small and derived from a single institution, which may not be representative of the broader Portuguese cancer care landscape.

Conclusion

This study highlights significant socioeconomic disparities in sarcoma care, even within universal healthcare systems, which may place vulnerable patients at greater disadvantage. In this context, our findings emphasize the potential role of patient advocacy groups in supporting patients through these challenges. These groups provide valuable resources, including information, reassurance, and emotional support. However, awareness of and contact with sarcoma-specific advocacy groups remain low, pointing to the need for greater efforts to raise their visibility. Socioeconomic differences extended across the care pathway: patients managed at SECs more often had higher educational levels and were less likely to have presented with symptomatic disease. Ensuring greater awareness of these organizations and improving the timeliness of referrals to SECs are critical steps toward enhancing patient care, facilitating access to vital resources, increasing patient engagement, and fostering a more patient-centered approach to sarcoma management. Prospective studies should determine whether engagement with advocacy groups influences treatment pathways and clinical outcomes.

Author contributions

Pau Mascaró-Baselga (Conceptualization, Data curation, Investigation, Methodology, Project administration, Resources, Visualization, Writing—original draft), Víctor Navarro (Data curation, Formal analysis, Visualization, Writing—review & editing), Ana Sebio (Investigation, Writing—review & editing), Rosa Álvarez (Investigation, Writing—review & editing), Sara Carvalho (Investigation, Writing—review & editing), María Ángeles Sala-González (Investigation, Writing—review & editing), Gloria Marquina (Investigation, Writing—review & editing), Javier Martínez-Trufero (Investigation, Writing—review & editing), Juana María Cano (Investigation, Writing—review & editing), Andrés Redondo (Investigation, Writing—review & editing), Aurea Molina-Díaz (Investigation, Writing—review & editing), Diego Gomez-Puerto (Investigation, Writing—review & editing), Carlo María Cicala (Investigation, Writing—review & editing), Miguel Henriques-Abreu (Investigation, Writing—review & editing), Claudia Valverde (Investigation, Writing—review & editing), Guillermo Villacampa (Formal analysis, Methodology, Supervision, Writing—review & editing), and César Serrano (Conceptualization, Investigation, Methodology, Project administration, Resources, Supervision, Writing—review & editing)

Supplementary material

Supplementary material is available at The Oncologist online.

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Conflicts of interest

P.M.B. reports travel support from Amgen, Eli Lilly, Pierre Fabre, Rovi, LEO Pharma, Ferrer, Servier. V.N. declares no conflicts of interest. A.S. reports consulting/advisory relationship with Springworks, Merck, Boehringer Ingelheim, Deciphera; honoraria from PharmaMar, Springworks, Deciphera; and travel support from PharmaMar, Deciphera, Cebiotex. R.A. reports consulting/advisory relationship with Boehringer Ingelheim, Merck, Novartis, Roche; honoraria from Pfizer, Deciphera, PharmaMar; travel support from Deciphera, PharmaMar, Roche, MSD Oncology; and participation as clinical trial investigator (no personal compensation) for AstraZeneca, Boehringer Ingelheim, Cebiotex, Janssen Oncology, Novartis, Pfizer, Rain Therapeutics, Roche. S.C. reports travel support from MSD, AstraZeneca, GSK, Lilly. M.A.S.G. reports consulting/advisory relationship with PharmaMar, Pierre Fabre, Regeneron; honoraria from AstraZeneca, Pfizer, Deciphera, Roche, PharmaMar; and travel support from Roche, Pfizer, AstraZeneca, PharmaMar. G.M. reports consulting/advisory relationship with PharmaMar, Clovis Oncology, GSK, Lilly, Pfizer, Boehringer Ingelheim, Deciphera, Eisai, AstraZeneca, Cogent Biosciences; honoraria from Roche, AstraZeneca, GSK, Clovis Oncology, Eisai, PharmaMar, Bayer, Lilly, Ipsen, MSD, Inhibrx Biosciences, Deciphera; and travel support from Roche, PharmaMar, GSK, MSD, Pfizer, Novartis, Merck, Lilly, Eisai, AstraZeneca, Angelini. J.M.T. reports consulting/advisory relationship with Boehringer Ingelheim, Deciphera, Eisai, GSK, PharmaMar, Springworks Therapeutics; honoraria from Eisai, Ipsen, Merck, MSD, Roche, Springworks Therapeutics; and travel support from PharmaMar, Roche. J.M.C. declares no conflicts of interest. A.R. reports consulting/advisory relationship with MSD, AstraZeneca, GSK, AbbVie, Pharma&; honoraria from MSD, AstraZeneca, GSK, AbbVie, Pharma&; and travel support from AstraZeneca, GSK. A.M.D. declares no conflicts of interest. D.G.P. reports consulting/advisory relationship with Clinigen; and travel support from PharmaMar, Servier. C.M.C. reports honoraria from Deciphera Pharmaceuticals, Orion Pharma; and travel support from Deciphera Pharmaceuticals, PharmaMar. M.H.A. reports consulting/advisory relationship with Novartis, Gilead, GSK, PharmaMar, Deciphera, MSD, AbbVie; honoraria from Daiichi Sankyo, Novartis, AstraZeneca, MSD, PharmaMar, Merck, Lilly, AbbVie; and travel support from MSD, AstraZeneca, GSK, Lilly, PharmaMar. C.V. reports consulting/advisory relationship with Eli Lilly, Bayer, Boehringer Ingelheim, Deciphera, Cogent, Mundipharma, Springworks, GSK; honoraria from MSD, PharmaMar, Deciphera; institutional research funding from PharmaMar, Bayer, Roche, Mundipharma, Boehringer Ingelheim, GSK, Lilly, Adaptimmune, Karyopharm, Foghorn Therapeutics, Inhibrx Biosciences, Servier, iOMX Therapeutics, MSD, Ayala Therapeutics, Rain Therapeutics, Immunome, Philogen, Cebiotex, PTC Therapeutics, Peptomycs; and an unpaid leadership role as Board of Directors and Chair (2018–ongoing) of GEIS and as an OECI auditor. G.V. reports consulting/advisory relationship with Reveal Genomics; and honoraria from Pfizer, MSD, GSK, Pierre Fabre, AstraZeneca. C.S. reports consulting/advisory relationship with Bayer, NewBay, IDRX, Cogent, Deciphera; institutional research funding from IDRX, Blueprint Medicines; honoraria from Roche, PharmaMar, Deciphera; and travel support from Gilead, PharmaMar, Pfizer, Bayer AG.

Data availability

The data underlying this study were obtained from anonymous surveys collected across participating centers and contain sensitive patient-level information. For ethical and legal reasons, the data are not publicly available. De-identified data may be shared upon reasonable request to the corresponding author, subject to approval by the participating centers and relevant ethics committees.