To the Editor,
Sebaceous carcinoma (SC) is a rare malignant adnexal neoplasm that shows sebocytic differentiation. It usually involves sun-exposed areas, particularly the head and neck. However, immunosuppression, such as that seen in organ transplant recipients, increases the likelihood of atypical and aggressive cutaneous malignancies, including SC (1). This report presents a rare case of rapidly growing SC in a non-ultraviolet (UV) exposed area in a kidney transplant patient under chronic immunosuppression.
A 60-year-old fair-skinned male presented with a rapidly enlarging skin lesion on the left upper trunk, which had developed over the previous 6 months. Eleven years earlier, he had undergone a kidney transplant and was receiving oral prednisone, tacrolimus, and azathioprine for immunosuppression.
Dermatological examination revealed a 2 cm, exophytic, non-pedunculated nodule with yellow and pink hues on an erythematous base, accompanied by signs of inflammation (Figure 1). Excisional biopsy was performed with primary closure. Histopathological analysis confirmed SC (Figure 2). Although no tumor was observed at the surgical margins, the lesion was within 1 mm of the closest margin.
Postoperative staging included full-body computed tomography and ultrasonographic evaluation of the left axillary region. No metastatic or pathological lymph nodes were detected. Due to the close margin, a wider re-excision was carried out. Immunosuppressive therapy continued unchanged. The patient was followed for one year without recurrence or metastasis.
Sebaceous carcinoma is a rare but aggressive tumor with metastatic potential, particularly in immunocompromised hosts. The presented case is notable for its trunk localization, which is atypical due to the limited exposure to UV radiation. Immunosuppressive agents—particularly calcineurin inhibitors such as tacrolimus—are known to increase cancer susceptibility (2).
Surgical excision remains the primary treatment approach for SC, and lymph node dissection or adjuvant therapies may be considered depending on the stage and metastatic involvement. In our case, the absence of lymphovascular invasion or metastatic disease justified treatment with surgical excision alone. Given the reported aggressive nature of SC, close clinical surveillance was maintained for one year, during which no adverse findings were observed (3).
Sebaceous carcinoma should be considered in the differential diagnosis of rapidly growing skin lesions in immunosuppressed individuals, even when located in non–sun exposed regions. Early diagnosis and adequate surgical intervention are essential. This case underscores the importance of vigilant skin examination and monitoring in kidney transplant recipients under chronic immunosuppressive therapy.
