Daijiworld Media Network - London
London, Oct 26: A 93-year-old woman with an eight-month history of a bleeding, ulcerated lesion on her left nipple was initially diagnosed with undifferentiated sarcoma, but further examination after surgery revealed invasive melanoma, highlighting the diagnostic challenges posed by this rare malignancy.
The lesion measured approximately 3–4 cm and appeared as a firm, purplish, protruding mass. Breast imaging identified a suspicious nipple mass measuring 44 × 35 mm, along with enlarged axillary lymph nodes. However, fine-needle aspiration did not reveal malignant cells, while a CT scan showed no evidence of distant disease.
An initial core biopsy suggested undifferentiated sarcoma, prompting doctors to perform a modified radical mastectomy and axillary lymph node dissection.
Further histopathological examination identified ulcerated, invasive superficial spreading melanoma of the nipple-areolar complex. The tumour had a Breslow thickness of at least 60 mm and a mitotic rate of seven mitoses per square millimetre.
The tumour displayed considerable cellular variability and inconsistent expression of melanocytic markers. Although the initial biopsy tested negative for S100, subsequent immunohistochemical testing showed patchy positivity for S100, Melan-A, HMB45, PRAME and tyrosinase.
The findings highlighted how limited tissue sampling can overlook important diagnostic features, particularly in poorly differentiated malignancies.
All 15 dissected axillary lymph nodes were found to be free of cancer, and the surgical margins were clear. The melanoma was classified as Stage IIC (pT4bN0M0).
Following a multidisciplinary review, the medical team decided against adjuvant treatment, primarily taking the patient's advanced age into consideration. She remained disease-free 26 months after diagnosis.
The case also raises questions about the most appropriate surgical approach for melanoma affecting the nipple. Although mastectomy was performed following the initial sarcoma diagnosis, a review of published cases indicated that such lesions are increasingly managed according to established principles for cutaneous melanoma.
Wide local excision is generally preferred over mastectomy, which has not demonstrated a survival advantage. Sentinel lymph node biopsy also plays an important role in assessing the spread of the disease to regional lymph nodes.
Primary melanoma of the nipple-areolar complex is exceptionally rare and can resemble Paget's disease, breast carcinoma or benign pigmented lesions. The condition can occur in patients of any sex, making awareness of its varied presentation important.
The case underscores the need to consider melanoma when evaluating persistent nipple abnormalities. Comprehensive histopathological examination, appropriate biopsy sampling and expanded immunohistochemical testing can help prevent diagnostic errors and guide treatment, potentially avoiding unnecessarily extensive surgery.