Surgical treatment of Peyronie’s disease by plaque incision and buccal mucosa graft: a systematic review and meta-analysis

Abstract

Peyronie’s disease (PD) is a debilitating condition affecting the sexual and psychological health of millions of men and their partners around the world. Plaque incision (PI) surgery with buccal mucosa graft (BMG) is a promising option for patients with PD. This systematic review aims to comprehensively assess the efficacy of PI with BMG in the management of PD. PubMed, Scopus, Web of Science, Embase, CENTRAL, and Clinicaltrials.gov were systematically searched for possible keywords to include full-text studies and abstracts. After full-text screening and extraction, the quality of included studies was assessed using the National Institutes of Health (NIH) study quality assessment tools. Open Meta-Analyst software was used with a random effect model for all analyses. Seventeen reports were included in the current systematic review, including nine full-text reports and eight abstracts. Meta-analysis of the included data revealed that PI with BMG showed a success rate of 98.6%, a satisfaction rate of 92.1%, and a very low de novo erectile dysfunction rate of 1.7%, with a penile shortening rate of 1.1%. The International Index of Erectile Dysfunction and the length of the affected side significantly increased by 1.69 points and 1.99 cm, respectively. Head-to-head analysis showed comparable outcomes between BMG and other grafting methods. PI with BMG seems to be an effective treatment for PD with comparable potential to other grafting methods. Further randomized clinical trials are needed to evaluate the efficacy of PI with BMG in comparison to other grafting techniques.

INTRODUCTION

Peyronie’s disease (PD) is a medical condition characterized by the formation of a plaque or scar tissue in the erectile tissue of the penis causing penile deformities and abnormal curvature of the penis.1 PD is a widely prevalent disorder with prevalence ranging from 0.3% to 7.1%, which may increase to 20.3% in specific populations like diabetics and patients suffering from erectile dysfunction (ED).2 PD deformities cause pain, ED, and sexual dissatisfaction for the patients and their partners, with subsequent deterioration of the psychological health and quality of life. There have been several conservative treatments for PD, especially for the acute phase of the disease.

The acute phase usually takes less than 6 months, is hallmarked by pain and inflammation, and is mainly managed with non-steroidal anti-inflammatory drugs, in addition to the recently added intralesional injection.3 However, surgery remains the gold-standard treatment option for chronic disease and severe cases, including penile plication, incision, or excision with grafting, where plaque incision (PI) and grafting represent the most popular technique, especially for severe cases. There are many grafting materials to provide the best functions and the lowest adverse effects, including autografts (from the patient), allografts (from other humans), xenografts (from animals), and synthetic grafts.4

The best grafting method should be available and cheap, and has the best functional outcomes. Autografts were much considered in recent research for its availability, flexibility, and the minimal associated incidence of infection. Autografts, including saphenous vein, tunica vaginalis, and buccal mucosa, have been used with varying success rates.5 Recent studies supported the efficacy of PI with buccal mucosa grafting (BMG) and its comparability to other long-established techniques.6,7 However, the state of evidence is still unclear.

A previous systematic review investigated the efficacy of different grafting methods in Peyronie’s surgery.5 BMG resulted in the highest penile straightening rates and the lowest incidence of de novo ED among all grafting methods. However, a limited number of studies on BMG were involved, with a lack of assessment of other safety and efficacy parameters. There was no direct comparison of PI with BMG with other grafting methods as well. The guidelines of Cochrane recommended a broad systematic review to comprehensively assess the evidence on each intervention.8 Therefore, this systematic review and meta-analysis aimed to comprehensively assess the evidence of plaque incision with BMG for the treatment of PD.

Cochrane Handbook rules and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement guidelines were followed throughout the current systematic review and meta-analysis.8,9 The study protocol was pre-specified and registered on the International Prospective Register of Systematic Reviews (PROSPERO; No. CRD42024571186).

Inclusion and exclusion criteria

The following criteria were used to include studies in the study analysis: (1) all types of studies evaluating the effectiveness of plaque incision and BMG; (2) participants aged 18 years old or elder with PD; and (3) full-text and abstracts (when the full-text was unavailable) were included. The inclusion of the abstracts is supported by Cochrane instructions and the recommendations of Scherer and Saldanha10 on gray literature, to minimize publication bias and to provide a more comprehensive view of the state of the evidence. Review articles and studies on other grafts or operations were excluded. Trials that were published repeatedly were excluded and the latest study was included.

Information sources and search strategy

PubMed, Scopus, Web of Science, Embase, CENTRAL, and Clinicaltrials.gov were systematically searched from inception till July 2024 for relevant keywords. For example, our search strategy for PubMed was (“Peyronie’s disease” or Peyronie or Peyronies) AND (“plaque incision” or plaque) AND (“buccal mucosa” or “buccal grafting” or buccal). We did not restrict the search by any date or language. We manually searched Google Scholar and screened references for potential studies.

Screening and data selection

Two blinded authors (AA and AR) conducted the two screening phases. First, they screened the titles and abstracts of the retrieved articles using the Rayyan app.11 Second, the full text of eligible studies was retrieved and screened using a spreadsheet. Any apparent conflicts among the review authors were addressed through a discussion with a third author (MR). Authors of unreachable studies were contacted; otherwise, abstracts were included when the full-text could not be reached.

Data extraction

Data were gathered using a pre-designed extraction sheet, including study ID (last name of first author and year), study design, country, full article or abstract, number of patients, duration of follow-up, duration of the disease, mean age of patients, preoperative curvature degree, adverse events, and summary of the studies. A discussion with the primary author resolved any conflicts.

Evaluation of the quality of studies

The National Institutes of Health (NIH) study quality assessment tools were used to assess the quality of evidence of the included full-text studies. The following tools were used: the Quality Assessment Tool for Before–After (Pre–Post) Studies which included 12 items, the Quality Assessment Tool for Case Series Studies which included 9 items, and the Quality Assessment tool for Controlled Intervention Studies which included 14 items. An overall score is calculated, and an overall quality assessment is determined as good, fair, and poor.12,13 Abstracts were not assessed due to limited information.

Statistical analyses

All statistical analyses were performed using Open Meta-Analyst software for Windows 10.14 Continuous outcomes were represented as mean difference of change (MD) with corresponding 95% confidence interval (CI), while proportion outcomes were expressed as percentage (%) and 95% CI. Significant heterogeneity was considered when the Chi-square P-value was less than 0.1 or the I² was greater than 50%. A random effects model was used to pool the results of the included studies to account for potential heterogeneities. P < 0.05 was considered statistically significant. Publication bias was countered with a search through several databases for papers and clinical trials and by the inclusion of the abstracts. However, inspection of the funnel plot was not possible due to the low number of studies.

Missing data were requested from corresponding authors, and if not received, it was calculated from available data. Mean and standard deviation (s.d.) were calculated from the median and interquartile range (IQR)/range using the equations provided by Wan et al.15 Abstracts were excluded from meta-analysis to provide the higher quality of results and were qualitatively represented in the tables and the articles.

STUDY SELECTION AND CHARACTERISTICS OF INCLUDED STUDIES

Out of 94 studies found through the initial search, 17 studies6,7,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30 were included in our systematic review, including nine full-text articles and eight abstracts (Figure 1). Most of the full-text studies were from Italy, followed by Kazakhstan, Türkiye, and Spain. Abstracts were additionally from Russia, Germany, Egypt, China, Bulgaria, and North Macedonia. The full-text studies contained information from 261 patients (BMG = 218) suffering from PD. All studies used the plaque incision method and had at least one arm using BMG. Two studies6,7 were double comparing BMG directly to other grafting methods, while the other studies were single arm (prospective or retrospective), case studies, or series. The results of the quality assessment led to the categorization of 3 studies6,16,17 as good quality showing good adherence to methodological standards, while the rest of the studies were of fair quality showing some defects (Table 1).

Figure 1.

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow diagram of the selection process.

Table 1.

Summary of the included studies

Study	Study design	Full-text or abstract	Country	Grafting method	Number of patients	Adverse events	Summary of the findings	Quality
Ainayev et al.162021	Prospective single arm	Full-text	Kazakhstan	BMG	20	Seroma and hematoma were seen in 2 and 5 patients, respectively, which resolved spontaneously	High success rates (90% at 24 months), no penile shortening or new erectile dysfunction occurred, and 10% of patients were dissatisfied	Good*
Ainayev et al.6 2022	Prospective double arm	Full-text	Kazakhstan	BMG and TVG	20	Seroma and hematoma were seen in 2 and 5 patients, respectively, which resolved spontaneously	Both buccal and tunica vaginalis grafts were effective and there was no significant difference between the two groups	Good***
					20
Cormio et al.17 2019	Prospective single arm	Full-text	Italy	BMG and BMG + TAB	29	There are no intraoperative complications. Glans numbness was reported by 6 (8.3%) patients	BMG, with or without TAP, achieved 100% penile straightening, 100% ability to obtain an erection, 97.1% ability to penetrate without (85.3%) or with (11.8%) PDE5i is 89.7% ability to complete intercourse, and 86.8% satisfaction with intercourse	Good*
					43
Cormio et al.18 2009	Prospective single arm	Full-text	Italy	BMG	15	There were no intraoperative or postoperative complications	All patients resumed unassisted intercourse 1 month after surgery. Postoperative evaluation showed 100% penile straightening and 93.3% patient satisfaction	Fair*
Danacıoğlu et al.7 2021	Retrospective double arm	Full-text	Türkiye	SVG	23	Ecchymosis was observed in the penile shaft of one (5.5%) patient from the BMG group	Both grafting techniques with PI were effective with no complications or significant differences between them	Fair***
				BMG	18
Molina Escudero et al.19 2015	Case study	Full-text	Spain	BMG	1	No complaints were reported	A year later, the patient preserves erectile function without the use of drugs, with a penile length of 9.2 cm	Fair**
Fabiani et al.20 2021	Retrospective single arm	Full-text	Italy	BMG	27	Hemorrhage at the donor site: 1 Penile shaft hematoma: 1 Glandular erection pain: 1 Preputial edema: 4 Skin necrosis: 1 Cystic intra-graft lesions: 3 Penile abscess: 1 Recurvatum relapse: 0 De novo erectile dysfunction: 2	BMG resulted in 100% success rates of penile straightening with 2 cases of post-operative erectile dysfunction	Fair*
Fabiani et al.21 2016	Case series	Full-text	Italy	BMG	17	Hemorrhage at the donor site: 1 De novo erectile dysfunction: 1 Penile shaft hematoma: 1 Glandular erection pain: 1	BMG resulted in 100% success rates of penile straightening with 1 case of post-operative erectile dysfunction and no replacement and 94% satisfaction	Fair**
Zucchi et al.22 2015	Retrospective single arm	Full-text	Italy	BMG	28	1 patient had curvature relapse, and 1 patient had slight erectile dysfunction	Patient satisfaction was 85% on the Patient Global Impression of Improvement questionnaire. Twenty-five partners were satisfied (90%)	Fair*
Liu et al.23 2009	Case series	Abstract	China	BMG	27	No complications were reported	Complete straightening of the penis was achieved in 21 patients, slight residual curvature (<15°) was noted in 3 patients, a little	NA
							shortening of the penis (<1 cm) in 2 patients, and erectile pain in 3 patients
Dmitrenko et al.24 2023	Prospective single arm	Abstract	Bulgaria	BMG	14 (BMG=10)	25.5% of patients had shortening of the penile body. In 21%, there was postoperative erectile dysfunction. 50% of patients found reduced sensitivity of the glans penis in the early postoperative period	Straightening of the penile body was achieved in 100% of cases	NA
Zahran et al.25 2016	Prospective single arm	Abstract	Egypt	BMG	15	Four patients encountered significant penile shortening >1 cm, and five patients encountered residual penile curvature >20°. De novo erectile dysfunction was encountered in all patients	All surgeries were successful. None of the 15 patients reported excellent satisfaction. The mean postoperative IIEF-5 score after 6 months was 12.3, and the percentage of yes responses to "did the treatment improve your ability to engage in sexual activity?" was only 13.3% and only two patients were just satisfied with the surgery	NA
El-Seweifi26 2010	Prospective single arm	Abstract	Germany	BMG	11	No complications were found	Penile straightening was documented in all patients without any shortening of the shaft. Satisfaction of the female partner was observed 6 weeks postoperatively. There was 1.8 mean increase in the IIEF-5. There is no recurrence during the follow-up period	NA
Gvasalia et al.27 2014	Retrospective single arm	Abstract	Russia	BMG	33	There were no donor-site complications	Of the 33 cases, complete straightening of the penis was achieved in 24 patients, while slight residual curvature (<15°–20°) was observed in the remaining cases (27%)	NA
Gvasalia et al.28 2017	Retrospective double arm	Abstract	Russia	BMG and saphenous allograph	BMG: 41  Saphenous allograph: 81	There were no donor-site complications in either group, and the donor site was better in the buccal mucosa graft site	Complete penile straightening in group BMG was achieved in 56% of patients versus 63% in the saphenous group (P=0.05). The overall satisfaction rate due to our questionnaire was 83% in group BMG and 85% in group saphenous	NA
Izairi29 2011	Prospective single arm	Abstract	North Macedonia	BMG	18	There were no intraoperative or postoperative complications	6 months postoperative evaluation showed 100% penile straightening, excellent rigidity, no penile shortening, no curvature recurrence or de novo erectile dysfunction	NA
Kotov and Usufov30 2019	Retrospective single arm	Abstract	Russia	BMG	35	NA	Postoperative penile straightening was achieved in 92.4% of patients	NA

^*NIH tool for pre-post studies; ^**NIH tool for case series studies; ^***NIH tool for controlled studies. BMG: buccal mucosa graft; TVG: tunica vaginalis graft; TAB: tunica-albicans; NA: not available; NIH: National Institutes of Health; PI: plaque incision; IIEF-5: International Index of Erectile Function-5; TAP: tunica albuginea plication; SVG: saphenous vein allograph; PDE5i: phosphodiesterase 5 inhibitor

The age of participants ranged from 46 years to 61 years, the follow-up time ranged from 13 months to 62 months, and the disease duration ranged from 15.3 months to 21.8 months. All studies accepting only participants with a minimum 6 months of Peyronie’s disease diagnosis (Table 2).

Table 2.

Baseline characteristics of the included studies

Study	Full-text or abstract	Grafting method	Number of patients	Follow-up time points (months after operation)	Follow-up time (month)	Age (year)	Duration of disease (month)	Preoperative curvature degree (°)	Preoperative IIEF-5 score	Length of affected side (cm)	Site of curvature
Ainayev et al.16 2021	Full-text	BMG	20	3, 12, and 24	NA	46.5±9.9a	16.7±6.8a	45b	17.5±2.2a	11±1.5a	Dorsal: 9 Ventral: 2 Lateral: 4 Dorsolateral: 3 Ventrolateral: 2
Ainayev et al.6 2022	Full-text	BMG	20	3, 12, and 24	NA	46.5±9.9a	16.7±6.8a	45b	17.5±2.2a	11±1.5a	Dorsal: 9 Ventral: 2 Lateral: 4 Dorsolateral: 3 Ventrolateral: 2
		TVG	20	3, 12, and 24	NA	47.2±10.8a	16.5±11.4a	48±6.6a	18.4±2.5a	11.5±1.2a	Dorsal: 13 Ventral: 2 Lateral: 4 Dorsolateral: 1
Cormio et al.17 2019	Full-text	BMG	29	1, 3, 6, and 12 months and yearly	62.01±34.3a	61.18±4.03a	15.29±4.93a	66.37±18.18a	21.53±1.89a	10.8±1.51a	Dorsal: 52 Lateral: 12 Ventral: 8
		BMG + TAB	43			59.45±5.9a	16.1±6.9a	74.65±17.43a	20.86±1.82a	10.83±1.1a
Cormio et al.18 2009	Full-text	BMG	15	1, 3, 6, and 12 months and yearly	13.1	56.3b	19.4	72±37a	21.3b	11.5b	Dorsal: 11 Dorsal+right: 1 Dorsal+left: 4 Ventral: 1 Left: 1
Danacıoğlu et al.7 2021	Full-text	SVG	23	1, 3, 6, and 12 months and yearly	18±4.8a	57.65±6.4a	21.8±5a	70±12.2a	19.2±2.7a	18.9±2.6a	Dorsal: 8 Ventral: 6 Lateral: 9
		BMG	18		17.7±3.9a	53.17±10.1a	20.2±5.5a	75±10.4a	18.9±2.6a	11.9±0.8a	Dorsal: 6 Ventral: 7 Lateral: 5
Molina Escudero et al.19 2015	Full-text	BMG	1	12	NA	55b	NA	90b	4b	10b	NA
Fabiani et al.20 2021	Full-text	BMG	27	72	28.3b	57±7.25a	16.5±10.5a	61.9±7a	22.5±1.5a	NA	Dorsal: 18 Ventral: 2 Complex: 7
Fabiani et al.21 2016	Full-text	BMG	17	30	21.47±8.77a	56.4±7.23a	17.2	57.4b	22.4b	NA	Dorsal: 10 Dorsal-HG: 1 Dorsal-HGD: 2 Dorsal-lateral: 1 Ventral: 1
Zucchi et al.22 2015	Full-text	BMG	28	6 and 12	43 (12–96)d	55b	NA	63.75±17.46a	21.5±2a	NA	Dorsal: 20 Dorsal + lateral: 5 Lateral: 1 Ventral + lateral: 1 Ventral: 1
Liu et al.23 2009	Abstract	BMG	27	NA	53 (24–72)d	NA	Between 1 year and 13 years	30–80c	NA	NA	Dorsal root: 15 Dorsal shaft: 6 Subcoronal shaft: 3 Ventral shaft: 3
Dmitrenko et al.24 2023	Abstract	BMG	14 (BMG=10)	NA	24b	35–61c	NA	NA	NA	NA	NA
Zahran et al.25 2016	Abstract	BMG	15	6	NA	56.7b	NA	65b	NA	11.3b	NA
El-Seweifi26 2010	Abstract	BMG	11	3, 6, 12, 18 and 24	14.8b	46.6b	NA	NA	NA	NA	NA
Gvasalia et al.27 2014	Abstract	BMG	33	NA	42b	46 (23–70)d	NA	<30c	NA	NA	Dorsal: 23 Ventral: 10
Gvasalia et al.28 2017	Abstract	BMG	BMG: 41 Saphenous allograph: 81	NA	BMG: 70b Saphenous allograph: 46b	NA	NA	NA	NA	NA	NA
Izairi29 2011	Abstract	BMG	18	1, 3, 6, and 12	NA	53.8b	NA	68b	NA	NA	NA
Kotov and Usufov30 2019	Abstract	BMG	35	3 and 12	28.9±13.7a	54.1±8.23a	NA	82.8 (45–120)d	NA	NA	NA

^aMean±s.d. ^bMean. ^cRange. ^dMedian (IQR). BMG: buccal mucosa graft; TVG: tunica vaginalis graft; TAB: tunica albicans; SVG: saphenous vein allograph; NA: not available; IIEF-5: International Index of Erectile Function-5; s.d.: standard deviation; IQR: interquartile range

META-ANALYSIS OF SURGERY SUCCESS AND SATISFACTION RATES

Six studies6,7,17,18,20,22 (n = 176) reported success rates defined as residual penile curvature <15°, where meta-analysis supported PI with BMG to have the significantly highest success rate of 98.6% (95% CI: 96.8%–100.3%, P < 0.0001; Figure 2). The studies were very homogenous with I² = 0. This result was further supported by high satisfaction rates reported in five studies (n = 133), where the meta-analysis showed a significant satisfaction rate of 92.1% (95% CI: 88.1%–96.0%, P < 0.001), with no significant heterogeneity (I² = 0). As shown in Figure 3.

Figure 2.

Meta-analysis of success rates. 95% CI: 95% confidence interval.

Figure 3.

Meta-analysis of satisfaction rates. 95% CI: 95% confidence interval.

POST-OPERATIVE DE NOVO ED AND PENILE SHORTENING RATES

Seven studies6,7,17,18,20,21,22 (n = 193) reported results on post-operative de novo ED and the results of the meta-analysis found a very low proportion of 1.7% (95% CI: −0.1%–3.5%, P = 0.068, I² = 1%; Figure 4). In addition, three studies reported results on penile shortening after the operation and the pooled results were 1.1% (95% CI: −0.8%–3.0%, P = 0.268, I² = 0; Supplementary Figure 1 ^{(52.9KB, tif)} ).

Figure 4.

Meta-analysis of de novo erectile dysfunction. 95% CI: 95% confidence interval.

INTERNATIONAL INDEX OF ED AND LENGTH OF THE AFFECTED SIDE

Six studies6,7,18,20,21,22 (n = 125) examined the effects of PI with BMG on the International Index of Erectile Dysfunction-5 (IIEF-5). PI with BMG led to a significant increase in IIEF-5 score by 1.687 (95% CI: 0.966–2.407, P < 0.001) with high heterogeneity (I² = 81.88; Supplementary Figure 2 ^{(65KB, tif)} ). The heterogeneity was mainly caused by the study of Ainayev et al.,16 and after its exclusion, the results maintained its significance (MD = 1.343, 95% CI: 0.943–1.742, P < 0.001), and the heterogeneity improved (I² = 35.78%), as shown in Supplementary Figure 3 ^{(58.6KB, tif)} .

Meta-analysis of three studies7,17,18 (n = 101) showed PI with BMG to significantly elongate the length of the affected side of the penis by a mean of 1.989 cm (95% CI: 1.641–2.338, P < 0.001, I² = 77.45%; Supplementary Figure 4 ^{(49.2KB, tif)} ). However, there was high heterogeneity from the study of Cormio et al.,19 where results maintained their significance after its exclusion (MD = 1.815, 95% CI: 1.645–1.985, P < 0.001) with subsequent improvement of the heterogeneity (I² = 0) as shown in Supplementary Figure 5 ^{(48KB, tif)} .

BMG IN COMPARISON WITH OTHER GRAFTING METHODS

Two studies6,7 directly compared BMG with other grafting methods with plaque incision approach. Ainayev et al.16 found no significant differences between BMG and tunica vaginalis grafting (TVG) in success rates (90% for both), post-operative IIEF-5 scores (mean ± s.d.: 20.6 ± 2.6 for TVG vs 21.3 ± 2.2 for BMG), or other parameters, including penile curvature and Doppler measurements. Moreover, Danacioglu et al.7 compared BMG to saphenous vein graft (SVG) and found that both grafting methods were respectively comparable in success rates (88.8% vs 88.9%, P = 0.619), IIEF-5 scores at 12-month follow-up (P = 0.559), de novo ED (P = 0.744), and satisfaction rate (P = 0.553).

DISCUSSION

The exact mechanism of PD is still unknown. However, the acceptable theory is that a fibrous plaque is formed in the tunica albuginea of the corpora cavernosa of the penis that may result from penile trauma, microvascular injuries, and/or connective tissue disorders.31 The main benefit of PI with grafting is to avoid penile shortening by plaque excision.32 This was further supported by the current results which revealed increased length of the affected side with significantly low rates of penile shortening. However, these results look like other grafting methods evidenced by controlled studies in the present review, and further double-arm studies are needed to find the best grafting method for PD surgeries.

The current systematic review and meta-analysis revealed that PI with BMG has a high success rate with significantly improved satisfaction rates. Moreover, the significantly higher IIEF-5 scores indicate improved erectile functions, which was associated with increased penile length, in comparison with the pre-operative parameters. Furthermore, this approach was associated with a very low percentage of de novo ED and penile shortening. All analyzed data were homogenous and maintained their significance after sensitivity analysis and the exclusion of the two articles with heterogeneous data. Head-to-head comparison of different grafting methods showed comparable outcomes of BMG with SVG and TVG. However, the latter finding may be limited by the low number of included studies.

Most of the included studies defined success as the presence of postoperative penile curvature of <15°,6,16,17,18,20,21 or 20°.7 Most analyzed studies depended on the Patient Global Impression of Improvement (PGI-I) questionnaire to assess satisfaction, while others used the Sexual Encounter Profile (SEP)18 or did not assess patients’ satisfaction.6,20 Although satisfaction is a subjective measure, it is an important parameter to consider for such procedures concerned with sexual life. Therefore, a validated questionnaire capturing all aspects of PD is crucial. Using SEP, Cormio et al.17 found 13% of patients were dissatisfied with overall sexual intercourse, and 81% were not happy with the hardness or erected penis, despite the good erection they reported and the high ability to penetrate in almost 97%. This highlights the importance of addressing patients’ expectations before the operation and measuring their satisfaction in future studies, along with partner satisfaction, as well.

Several studies used BMG since Shioshvili and Kakonashvili33 first published their results on its uses for PD surgery on humans in 2005. The results of the present study, including all analyzed articles, showed comparable success and satisfaction rates with the previously published data. The evaluation of post-operative ED is one of the most important outcomes and has been evaluated by two methods in this study, including calculating the number of de novo cases of ED and through IIEF-5. Only one study used penile Doppler ultrasound and found improved penile circulation postoperatively.6 Despite using the first two methods seems to be easier and more applicable, further studies should consider using Doppler ultrasound to provide more objective measurements.

Compared to the broad review by Natsos et al.,5 the current study aimed to provide a more comprehensive review of PI with BMG in PD, by including more studies, conducting more quantitative and qualitative analyses, and providing a more in-depth insight into the evidence. Furthermore, more important outcomes were assessed in this meta-analysis, exploring the direct comparison between BMG and other grafting methods. Literature suggests that more than half of abstracts fail to be published, while positive results and higher quality are associated with higher publication rates.34 Investigating abstracts included in this systematic review revealed that three studies7,17,18 showed comparable high efficacy and low adverse event rates like full-text studies. In comparison, four studies23,24,25,30 showed either lower success rates or higher complications compared to the results of this meta-analysis of full-text studies. This may highlight slight potential publication bias favoring positive results.

This systematic review has several limitations that should be acknowledged. First, the inclusion of abstracts may have decreased the level of evidence. However, this decision was made to gain deeper insights into the state of evidence in the field. Nevertheless, abstracts were not included in the meta-analysis, helping to ensure the reliability of our findings. Second, certain analyses revealed significant heterogeneity. However, this was addressed by conducting sensitivity analyses which confirmed that our findings remained robust. Additionally, the limited number of patients included in the studies may restrict the generalizability of the current results. It is important to consider the potential impact of a smaller sample size on the overall conclusions drawn from the review. Furthermore, the lack of randomized controlled trials and the lower-than-optimal quality of some of the included studies contribute to a decrease in the overall level of evidence. It is worth noting that these limitations are not unique to the current study but reflect the general state of research in andrology in general and specifically in PD field.35

CONCLUSION

This systematic review and meta-analysis provide a comprehensive review of the evidence for the effectiveness of PI with buccal mucosal grafting in the treatment of PD. This approach was associated with very high success rates, high patient satisfaction, and improved erectile function. Although there were some cases of de novo ED and penile shortening, the overall outcomes were favorable. The comparison with other grafting methods did not show significant differences in outcomes. However, the limited number of studies and the unpublished abstracts in our review highlight the need for more studies to support our results. The search for the best grafting method for Peyronie’s surgeries is still ongoing and future randomized controlled trials are needed to provide decision-makers with definitive answers to the efficacy and disadvantages of each method. These studies shall consider measuring all aspects of PD to provide comprehensive evidence for decision-making.

AUTHOR CONTRIBUTIONS

HB, OS, and CB conceived and designed the study. AA, AR, MR, and NB carried out the literature screening, and data extraction and analysis. HB, CB, NB, AG, and DR carried out writing (review and editing). All authors participated in manuscript writing, and read and approved the final manuscript.

COMPETING INTERESTS

All authors declared no competing interests.

Supplementary Information is linked to the online version of the paper on the Asian Journal of Andrology website.

Supplementary Figure 1

Meta-analysis of penile shortening. 95% CI: 95% confidence interval.

Supplementary Figure 2

Meta-analysis of IIEF-5 scores. 95% CI: 95% confidence interval; IIEF-5: International Index of Erectile Function-5.

Supplementary Figure 3

Sensitivity analysis for IIEF-5 scores. 95% CI: 95% confidence interval; IIEF-5: International Index of Erectile Function-5.

Supplementary Figure 4

Meta-analysis of the change in length of the affected side. 95% CI: 95% confidence interval.

Supplementary Figure 5

Sensitivity analysis for the length of the affected side. 95% CI: 95% confidence interval.