Unusual metastasis of breast cancer to the paranasal sinuses: a case report

Abstract

Background

Breast cancer is the most common malignancy in women, with invasive ductal carcinoma being the predominant subtype. Although metastases commonly affect the bones, liver, lungs, and brain, involvement of the paranasal sinuses is exceedingly rare and poses significant diagnostic challenges.

Case presentation

A 70-year-old postmenopausal woman from Pakistan with a history of left-sided mastectomy and chemotherapy for invasive ductal carcinoma presented with an altered sensorium, aphasia, and reduced oral intake. Imaging revealed an aggressive, destructive lesion in the left frontal sinus, ethmoid air cells, and posterior parietal bone. Biopsy confirmed metastasis from the primary breast carcinoma. The patient received palliative radiotherapy and supportive care owing to her preference to avoid invasive interventions. Despite management, her condition progressively deteriorated, and she succumbed 2 years later. Paranasal sinus metastases are uncommon and often mimic rhinosinusitis, leading to a delayed diagnosis. Breast cancer metastasis to this region underscores the unpredictability of metastatic spread even years after the initial diagnosis. Management focuses on symptom control because surgical intervention is typically limited by anatomical constraints and the patient’s overall health.

Conclusion

This case highlights the importance of maintaining a high index of suspicion for atypical metastatic sites in survivors of breast cancer. Multidisciplinary approaches and patient-centered care are critical for optimizing quality of life in advanced disease stages.

Introduction

Breast carcinoma remains the predominant form of cancer among women, with international statistics indicating that invasive breast cancer constitutes 11.6% of newly diagnosed tumors in 2022 [1]. Invasive ductal carcinoma accounts for approximately 50–75% of all invasive breast cancers. Clinically, these tumors are typically palpable as breast masses owing to the pronounced fibrosis observed [2]. The three most commonly affected organs in breast cancer metastasis are the bones, liver, and lungs. Metastases can also occur in the brain and skin, but such instances are relatively uncommon [3]. Notably, involvement of the nasal cavity and paranasal sinuses in breast cancer metastasis is exceedingly rare, comprising only 8% of total paranasal sinus metastases derived from breast cancer [4, 5].

This case is particularly noteworthy not only because of the ectopic localization of the metastasis but also because the clinical presentation was delayed by 4 years following the initial diagnosis of invasive ductal carcinoma. The emergence of neurological symptoms, such as confusion and difficulties in speaking, may indicate involvement of the central nervous system. This type of presentation highlights the necessity for clinicians to be vigilant of metastatic disease in breast cancer survivors, even when traditional metastatic sites remain unaffected. Consequently, timely detection and comprehensive management facilitated by a multidisciplinary team are essential for mitigating local complications and preserving the patient’s quality of life in the later stages of disease progression. This case report aims to highlight the diagnostic challenges of breast cancer metastasis to the paranasal sinuses, which represent an exceptionally rare site of spread, and to contribute to the limited literature by raising awareness of this unusual clinical presentation among clinicians.

Case presentation

A 70-year-old Pakistani woman, postmenopausal for 8 years, with a history of type 2 diabetes mellitus and hypertension, and no family history of breast cancer, presented to the emergency department with altered sensorium accompanied by decreased oral intake and aphasia that had persisted for the past 4 days. The patient reported no history of visual disturbances, syncope, vomiting, fever, or headaches. She underwent a left-sided mastectomy and level 2 axillary clearance for invasive ductal carcinoma located in the upper outer quadrant of the left breast 4 years prior (Fig. 1), which was estrogen receptor-positive, progesterone receptor-negative, and HER2/neu-positive. The following was observed: tumor size 3.2 cm, grade II, lymph node status 2/15 positive, Ki67 25%, estrogen receptor (ER)-positive (Allred score 7), progesterone receptor (PR)-negative, HER2 IHC 3+. Lymphovascular invasion was identified. On the basis of these findings, the tumor was staged as pT2N1 according to the American Joint Committee on Cancer (AJCC) classification. Following mastectomy, the patient’s adjuvant therapy was delayed, and radiotherapy was administered 2 years later because she could not afford timely treatment and lived at a considerable distance from tertiary care hospitals. Chemotherapy was subsequently initiated at the time of metastatic progression.

Fig. 1.

Mammography of the left breast in mediolateral oblique (A) and craniocaudal (B) views demonstrates an ill-defined, high-density lesion with spiculated margins and adjacent fat stranding involving the retroareolar region of the upper outer quadrant. Yellow arrows indicate the primary malignant breast lesion. Post-contrast computed tomography axial (C) and coronal (D) images show a heterogeneously enhancing, ill-defined mass in the left breast retroareolar region with surrounding fat stranding, subcutaneous tissue thickening, and involvement of the overlying skin (yellow arrows). No axillary lymphadenopathy is identified

Upon examination, bilateral downgoing plantar reflexes were noted, and motor reflexes remained intact; however, the gag reflex was absent. A diminished sense of smell suggested a potential nasal obstruction or congestion. A noncontrast computed tomography (CT) scan of the brain revealed an aggressive, destructive lesion affecting the left frontal sinus and ethmoid air cells, accompanied by a soft tissue component that involved the posterior parietal bone and extended to the extradural space (Fig. 2), although no definitive intracranial extension was observed. Biopsy confirmed that the metastatic mass originated from an initial diagnosis of invasive ductal carcinoma of the breast. Immunohistochemical analysis of the paranasal sinus lesion revealed morphology consistent with metastatic invasive ductal carcinoma. The lesion remained ER- and HER2-positive, and PR-negative, consistent with the primary tumor profile. In addition, GATA3 immunostaining was positive, further supporting the diagnosis of breast carcinoma metastasis.

Fig. 2.

Noncontrast computed tomography scan of the brain demonstrating an aggressive, destructive lesion involving the left frontal sinus and ethmoid air cells with an associated soft tissue component (A, yellow arrows). Additional involvement of the posterior parietal bone is seen with soft tissue extension up to the extradural space (B, yellow arrows), without definite intracranial parenchymal invasion

The patient opted for palliative care and expressed a desire to avoid invasive treatment options. Palliative radiotherapy was administered to the left chest wall and axilla following mastectomy for symptomatic metastasis, along with psychosocial support and symptomatic treatment, as necessary. Unfortunately, the metastasis did not respond to palliative radiotherapy, and the patient’s condition deteriorated, ultimately leading to death 2 years after her initial presentation to our facility.

Discussion

This case illustrates the diagnostic challenges and poor prognosis associated with paranasal sinus metastasis from breast carcinoma, a rare entity that requires heightened clinical suspicion. The ethmoid sinus, owing to its high vascularization and anatomical proximity to the orbit and cranial base, is susceptible to hematogenous spread; however, such occurrences remain relatively rare. In the present case, metastasis to the ethmoid sinus was identified 4 years after the primary diagnosis, indicating the unpredictable nature of metastatic breast cancer even after an extended disease-free interval.

Breast cancer cells that develop metastatic potential undergo alterations in their original characteristics, resulting in increased invasiveness, a phenomenon that is influenced by the tumor microenvironment. This process encompasses the activation of pathways such as epithelial–mesenchymal transition and various epigenetic modifications [6].

Literature indicates that metastatic breast cancer within the sinus region is associated with notably high mortality rates; however, effective treatment may enhance survival rates and, importantly, improve quality of life [4].

Imaging modalities, such as magnetic resonance imaging (MRI) or computed tomography (CT), are imperative for diagnosing metastatic sinus disease, while biopsy is essential for histopathological confirmation. In this specific instance, neurological signs necessitated neuroimaging to exclude the possibility of intracranial invasion or brain metastasis. From a therapeutic standpoint, managing sinus metastasis via surgical intervention poses significant challenges, attributed to both the anatomical location and the patient’s overall health status. Symptom management, particularly in cases involving pain or sinus obstruction resulting from metastasis, can be achieved through targeted radiotherapy directed at the sinus site. In scenarios involving concurrent central nervous system (CNS) involvement, systemic treatment options, including hormone therapy or chemotherapy, may be considered [3].

Recent literature, including findings by Pittoni et al., highlights the complexities associated with paranasal sinus metastasis of breast cancer, particularly in older female patients. The clinical trajectory of the patient in this study deteriorated over 2 years, ultimately resulting in death, underscoring the poor prognosis associated with nonsurgical treatment approaches. The present case demonstrates an initial symptomatic improvement with chemotherapy, supporting the premise that individualized treatment strategies can enhance clinical outcomes. These variations underscore the necessity for patient-tailored treatment regimens that account for both patient history and preferences [4].

Comparatively, the cases discussed by Davey and Baer illustrate a pattern of rapid clinical decline linked to metastatic breast cancer. A notable contrast was observed in the progression of the disease; our patient succumbed after 2 years, whereas a 75-year-old woman displayed deterioration within a mere 6 weeks following her initial definitive diagnosis. This rapid disease progression emphasizes the aggressive nature of the metastatic process and highlights the critical importance of effective symptom management alongside the realization of palliative care for affected patients [7].

Currently, advances in the management of metastatic breast cancer involving rare sites, including the paranasal sinuses, remain limited. Survival outcomes are largely influenced by the efficacy of systemic therapies. The presence of neurological symptoms complicates management, as CNS involvement is often associated with lower survival rates and a significantly diminished quality of life. Although other therapeutic avenues may yield immediate clinical benefits, they are generally considered chronic conditions, necessitating a focus on symptomatology [3].

Breast cancer metastases are observed in over 50% of patients, commonly affecting the bone, lungs, liver, and brain, whereas head and neck involvement is relatively uncommon. A heightened index of suspicion should be maintained, particularly for patients with a history of malignancies [8]. Symptoms associated with paranasal sinus metastasis often mimic rhinosinusitis, which can result in delayed diagnosis. Determining the appropriate treatment strategy in such cases is exceedingly challenging because radical surgical options are typically not feasible, with surgical intervention primarily limited to biopsy for differential diagnoses [9, 10]. Most patients receive palliative radiotherapy in combination with chemotherapy [11]. Literature reports a diagnostic interval for paranasal metastasis following breast cancer diagnosis ranging from 3 months to 12 years, with mechanisms facilitating metastasis to the paranasal sinuses. Tissue biopsies are essential for accurate diagnosis, necessitating close collaboration among oncologists, radiologists, and pathologists [9, 12].

Conclusion

Breast cancer metastasis to the paranasal sinuses is an exceedingly rare phenomenon that poses significant diagnostic and therapeutic challenges. This case emphasizes the necessity of maintaining heightened awareness of atypical metastatic sites in individuals with a history of breast cancer, even many years after the initial diagnosis. Diagnostic imaging modalities such as computed tomography (CT) and magnetic resonance imaging (MRI) are essential for establishing an accurate diagnosis. Although treatment options are frequently limited to palliative care owing to the anatomical location of the metastasis and the overall health status of the patient, prompt and multidisciplinary management can facilitate symptom relief and enhance the patient’s quality of life. Furthermore, this case illustrates the unpredictable nature of metastatic breast cancer and the critical need for patient-centered treatment strategies that consider individual preferences and clinical circumstances. Increased awareness of such rare metastatic presentations is crucial to optimizing outcomes in the management of advanced breast cancer.

Author contributions

HS: conceptualization, data curation, investigation, and writing—original draft. AK: project administration, supervision, writing—original draft, and writing—review and editing. IS: conceptualization, data curation, investigation, writing—review and editing, and correspondence. AHH: conceptualization, writing—original draft, and writing—review and editing.

Funding

We received no funding for this study.

Data availability

Data are available on request from the authors.

Declarations

Ethics approval and consent to participate

Formal ethical approval was waived because this study involved a single retrospective case report with no experimental intervention. Patient confidentiality was strictly maintained.

Consent for publication

Written informed consent was obtained from the patient for publication of this case report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal.

Competing of interests

The authors declare no conflicts of interest.