Case Study Features Rare Primary Merkel Cell Carcinoma Without Skin Involvement
Posted: Tuesday, January 5, 2021
Although uncommon, some patients may develop primary ectopic or metastatic Merkel cell carcinoma in noncutaneous sites, according to researchers from Democritus University of Thrace, Greece. This case study identified Merkel cell carcinoma in a mass located in the adipose tissue of the upper arm without skin involvement. These results were published in the Journal of Surgical Case Reports.
“It should be highlighted that the patient did not present any of the risk factors for Merkel cell carcinoma; moreover, the absence of a skin lesion could also be misleading and contribute [to] delayed diagnosis in a more advanced stage and, subsequently, shorter survival,” reported Nicolaos Lyratzopoulos, MD, and colleagues.
The patient was a 63-year-old woman with a complaint of a mass in the inner side of her right arm, with no other symptoms or related medical history. The soft, painless, mobile mass had doubled in size within 4 months of initial examination. Although there were no visual markers on the epidermis, the axillary lymph nodes were enlarged. Due to the rapid enlargement of the mass, an MRI, CT scan, and PET scan were utilized and excluded distant muscle, bone, or tissue involvement. The mass was subsequently excised, and axillary lymph nodes dissected.
Pathologic examination of the mass revealed neoplastic cells with round nuclei and scant cytoplasm, necrosis, mitoses, and lymph cell infiltration. Further, the lymph nodes exhibited positive cytogenic markers via immunohistochemistry. The patient was diagnosed with Merkel cell carcinoma of the adipose tissue with metastatic axillary lymph nodes.
Postoperative radiotherapy was administered, and follow-up examinations occurred every 6 months for 5 years—with no evidence of recurrence. The patient is currently disease-free and in good health 8 years following her cancer diagnosis.
Disclosure: The study authors reported no conflicts of interest.