Hormone receptor-positive (HR+) breast cancer is known for its potential to recur many years after initial treatment. Although most recurrences occur within the first 5–10 years, late recurrence, especially beyond 15 years of age, is rare and isolated cutaneous recurrence is even less frequently reported. However, awareness of the possibility of extremely late and subtle local recurrences in patients with HR+ breast cancer has gradually increased over time. Clinicians should remain vigilant for atypical cutaneous changes near previous surgical sites, even decades after the initial treatment, and consider biopsy in the absence of classic signs of recurrence. We report the case of a 56-year-old woman who experienced an isolated cutaneous recurrence nearly 20 years after mastectomy for HR+ breast cancer, presenting with only faint erythema.

Granular cell tumor is a rare disease, and it is even rarer in the male breast. Although it is typically a benign tumor, due to its features and image findings, it can be easily misdiagnosed and managed as a malignant tumor. Therefore, the extent of the surgery can inappropriately be expanded. To avoid misdiagnosis and overtreatment, surgeons must perform a careful evaluation. We describe a case of a granular cell tumor of the male breast treated with mastectomy.