|Year : 2014 | Volume
| Issue : 2 | Page : 399-400
Merkel cell carcinoma: A rare presentation
Prosanta Kumar Bhattacharjee, Shyamal Kumar Halder, Rajendra Prashad Ray
Department of Surgery, I.P.G.M.E. and R/S.S.K.M Hospital, Kolkata, West Bengal, India
|Date of Web Publication||14-Jul-2014|
Prosanta Kumar Bhattacharjee
Flat no. 5, 4th Floor, Suryatoran Apartments, 114/A, Barasat Road, Kolkata
Source of Support: None, Conflict of Interest: None
A 33-year-old man presented with a lump at the right side of chest wall of 4 months duration which started bleeding suddenly from an ulcer at its center. Examination revealed a globular ulcerated mass 2 cm in diameter, on the anterior axillary fold, with adherent clot at its center. No regional lymphadenopathy was noted. Wide local excision with 2 cm margin was done. Biopsy report revealed malignant small round-cell tumor. Immunohistochemistry showed it to be cytokeratin-20-positive and S100-negative, suggesting the diagnosis of Merkel cell carcinoma. The patient did not receive any other adjuvant therapy. He is being followed-up for the last 4 years and has shown no features of recurrence so far.
Keywords: Merkel cell carcinoma, radical surgery, ulcer
|How to cite this article:|
Bhattacharjee PK, Halder SK, Ray RP. Merkel cell carcinoma: A rare presentation. J Can Res Ther 2014;10:399-400
| > Introduction|| |
In 1875, Friedrich S. Merkel first described human Merkel cells.  The term Merkel cell carcinoma (MCC) was first used in 1980.  MCC is a primary intra-dermal tumor, of neuroendocrine origin, seen mostly in Caucasians above 50 years of age on sun-exposed areas. It is a rare tumor of the skin with a very poor prognosis.
Only a few cases have been reported below 50 years, particularly in immunosuppressed individuals with a possible association with Merkel Cell Polyomavirus, which was first described in 2008 as one of seven known human oncogenic viruses. 
MCC commonly presents as a small, less than 2 cm, solid, painless erythematous intradermal mass, usually with no ulceration, and with early nodal metastases. ,
We report a rare case of MCC in a 33-year-old man who presented with acute bleeding from an ulcerated mass, which was promptly excised with wide local margins. In spite of the relatively aggressive nature of this neoplasm, the patient did not manifest any recurrence over the last 4 years of follow-up.
| > Case report|| |
A 33-year-old man presented with a painless, slowly growing mass over the right upper chest wall of 4 months' duration which had spontaneously ulcerated and started bleeding on the day of presentation. There was no recent history of trauma, pain, fever, or weight loss.
On examination, the patient was of average build and nutrition. There was a well-defined, firm, globular, non-tender mass approximately 2 cm in diameter over the right anterior axillary fold. The mass had a smooth surface; it was not fixed to the underlying structures but was fixed to the overlying skin. There was an ulcer at the center of the lesion about 0.5 cm in diameter. The ulcer had rolled-up margins, indurated base, and the floor had adherent clot. There was no clinically apparent regional lymphadenopathy.
Routine and laboratory studies including coagulation profile were unremarkable. Serological tests for HIV were nonreactive. Skiagram of the chest showed no abnormality.
The history and the clinical findings suggested a neoplastic lesion arising from the skin and hence, a wide local excision of the lump with 2 cm margin all around was decided upon promptly. The deeper plane of excision was just superficial to deep fascia. Cut surface was heterogeneous with cystic areas filled with blood.
Histopathology showed a monomorphic appearance with uniform round cells having scanty amphophilic to eosinophilic cytoplasm with vesicular basophilic nuclei with prominent nucleoli, fine granular apoptotic bodies, and mitotic figures in plenty. The lesion was well vascularized and showed areas of hemorrhage [Figure 1].
|Figure 1: H and E ×200; showing monomorphic uniform round cells eosinophilic cytoplasm with vesicular basophilic nuclei with prominent nucleoli, apoptotic bodies and mitotic figures|
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Immunohistochemistry report showed the tumor to be cytokeratin-20-positive and S100-negative, suggesting it to be MCC.
The patient did not receive any other adjuvant therapy. He is being regularly followed-up for the last 4 years and is doing well so far without any evidence of local or regional recurrence.
| > Discussion|| |
MCC is an unusual skin malignancy, which is often confused with amelanotic melanoma. MCC lacks distinctive clinical features, and as such it is difficult to diagnose clinically. By the time the diagnosis is made most of the tumors have metastasized to regional lymph nodes. Differential diagnoses include basal cell carcinoma, lymphoma, melanoma, and squamous cell carcinoma. Aging, sun exposure, and immunosuppression are recognized risk factors.  None of these risk factors was present in our patient.
Immunohistochemistry is required to diagnose MCC, as histopathology can only point to malignant round-cell tumor.  On histopathology, the triad of vesicular nuclei with small nucleoli, abundant mitosis, and apoptosis is only suggestive of MCC.
On immunohistochemistry, MCC is CK20-positive. It is negative for S100, and this helps in differentiating it from melanoma, metastatic small cell carcinoma of lung, and other round-cell tumors. 
Prognosis largely depends on the stage of the disease with 90% 5 years' survival in localized disease. The early presentation of our patient probably explains the absence of nodal metastasis. Presence of lymph node metastases is the most important predictor for survival. 
Patients presenting with nodal involvement or clinically evident systemic spread need proper radiological staging.
Surgery is the only curable form of treatment. Wide local excision, Mohs micrographic surgeries are recommended treatment in localized disease. 
Therapeutic lymph-node dissection is employed in patients with nodal involvement. Radiotherapy is indicated as an adjuvant therapy in nodal metastases, sometimes in combination with chemotherapy.  Chemotherapy primarily is used in metastatic MCC. 
In this reported patient, prompt and radical surgery proved to be curative. He was not administered any other adjuvant therapy and there has not been any recurrence, either local or distant, over the last 4 years' follow-up.
| > References|| |
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