Merkel cell carcinoma metastatic to the transverse colon: Disease free after six years - cure or just prolonged remission?

Abstract

Merkel cell carcinoma is an uncommon but highly immunogenic skin malignancy that has the potential to metastasize to any site in the body. Despite treatment many patients experience relapse, often to distant sites beyond the site of initial treatment. The development of distant soft tissue or visceral metastases is considered incurable, despite treatment with prognosis usually being measured in months. We report the case of an elderly man who developed colonic metastases from a head and neck primary and with treatment has survived disease free for over 6 years. Such reports are infrequently documented and highlight the unpredictable nature of this disease.

Metastatic Merkel Cell Carcinoma In The Splenic Flexure Of The Colon Mimicking Primary Colonic Carcinoma-A Case Report With Literature Review

“…Our literature review shows only 3 out of 9 cases of MCC with colon metastasis attained clinical remission [10,13,15]. Compared to our patient, all three case reports utilized adjuvant radiotherapy at the first occurrence of MCC.…”

An Extraordinary Cause of Colonic Obstruction: Merkel Cell Carcinoma of Unknown Primary

“…To date, there have been 8 cases documenting existing or recurrent MCC metastatic to the colon (Table 1 ). 8 – 14 Our case is the first describing MCCUP of the colon, highlighting the need for awareness of MCC and MCCUP as a root cause of neuroendocrine tumor of the GI tract. In patients with an extensive cancer history or who may be immunocompromised, a thorough GI workup inclusive of biopsy and pathologic staining is necessary to distinguish a potentially insidious malignancy.…”

“…Previously described cases of MCC metastatic to the colon were not tested for MCPyV and were linked to a known cutaneous lesion. [8][9][10][11][12][13][14] Confirmation of metastatic MCCUP to rare sites of the colon is difficult because of low incidence, lack of primary lesion, and range of symptomatic presentations. Diagnosis of cutaneous MCC is confirmed by biopsy of a suspicious lesion with appropriate ancillary immunohistochemical studies correlated with imaging studies and possible lymph node biopsy.…”

“…Prior reports of GI involvement have highlighted metastasis most commonly to the stomach, but metastases to the colon are exceedingly rare. 8 – 14 To our knowledge, MCC metastatic to the colon has not been documented in the absence of a corresponding primary cutaneous lesion. Described is a patient who presented with bowel obstruction secondary to a large, circumferential hepatic flexure colon mass.…”

Recurrence of Merkel cell carcinoma in the gastrointestinal tract: a case report

“…The second one reports the case of a patient who presented with hematochezia from MCC in the rectum [ 15 ]. A third case reports primary head and neck MCC with metastasis to the colon who survived for 6 years [ 16 ].…”