Merkel cell carcinoma in a patient with basal cell carcinoma: a case of localized disease with negative sentinel node biopsy.

INTRODUCTION

Merkel cell carcinoma (MCC) is a rare but aggressive neuroendocrine skin cancer with a high risk of recurrence and metastasis. It typically affects sun-exposed areas in elderly or immunocompromised individuals. Early diagnosis and management are essential due to its rapid progression and potential for early metastasis.

CASE PRESENTATION

We report the case of a 65-year-old male with a history of diabetes mellitus and basal cell carcinoma who developed MCC on his left upper extremity. Initial imaging, including a sentinel lymph node biopsy (SLNB) and magnetic resonance imaging (MRI), localized the tumor and assessed lymph node involvement. The SLNB was negative for metastasis, and a wide excision confirmed no residual MCC. Further imaging with positron emission tomography (PET) and computed tomography (CT) scans showed no distant metastasis, indicating localized disease. The patient underwent wide excision followed by radiation therapy (RT) (50 Gy in 25 fractions), experiencing mild post-radiation effects such as swelling and erythema.

CLINICAL DISCUSSION

MCC poses significant diagnostic and therapeutic challenges due to its nonspecific presentation and rapid progression. In this case, early detection and appropriate imaging allowed for timely intervention. Negative SLNB results and localized disease justified the use of wide excision and MC. Multimodal treatment, including surgery and radiation, is crucial in managing localized MCC.

CONCLUSION

This case emphasizes the importance of early detection, comprehensive imaging, and multimodal therapy in the management of MCC. Close follow-up remains essential, especially in cases with negative SLNB, to monitor for recurrence or metastasis.