Merkel Cell Carcinoma: A Retrospective Study on 48 Cases and Review of Literature

Abstract

Merkel cell carcinoma (MCC) is a rare and aggressive neuroendocrine tumor of the skin. Fourty-eight patients with MCC were observed at the Rare Hormonal Tumors Group of Cremona Hospital, 15 of these with unknown primary site. Due to rarity of Merkel cell carcinoma, clinical experience is generally limited. Data from our series confirm the current recommendations. Wide surgical excision must be associated with radiotherapy also in early stages in order to avoid local relapse and the rapid progression of disease. In advanced stages chemotherapy is the standard despite the short duration of responses and poor quality of life. The data of our series, characterized by a high demand for second opinion, offer some insight about the real rarity of the tumor, the difficulty of managing of disease in our country secondary to a wrong cultural approach to the problem, the indiscriminate use of molecules unnecessary and often expensive, the lack of protocols, and the presence of guidelines often ignored. This results in very poor survival associated with a very low quality of life, requiring to find the right direction towards a correct management of disease.

Somatostatin Receptors 2A and 5 Are Expressed in Merkel Cell Carcinoma with No Association with Disease Severity

“…Heterogeneous responses have been reported after use of SSTR-targeted therapies in MCC patients, including a therapeutic radioisotope combined with a somatostatin analogue [26,27,28] or use of systemic somatostatin analogues such as lanreotide and octreotide [23,24,25]. To what extent the level of expression of SSTR in NETs influences the response to somatostatin analogues remains unknown, although this relationship was previously demonstrated in acromegaly patients [58,59].…”

“…This is supported by the ability of SRI to detect MCCs and their metastases [17,18,19,20,21,22] as well as some cases of tumoural response to somatostatin analogues [23,24,25,26,27,28]. However, the efficacy of SSTR-targeted imaging and therapy in MCC patients is not uniform, suggesting that the in situ expression of SSTRs in MCCs may be heterogeneous.…”

The impact of 18F-FDG-PET/CT on Merkel cell carcinoma management

“…Only a few studies, principally in case-report framework, have studied the impact of 18 F-FDG-PET/CT in therapeutic evaluation [27,28]. However, at the metastatic stage, the efficacy of 18 F-FDG-PET/CT can be controversial, considering the current limited therapeutic resources (low efficiency of chemotherapy), and remains to be studied in larger cohorts [29]. However, at the metastatic stage, the efficacy of 18 F-FDG-PET/CT can be controversial, considering the current limited therapeutic resources (low efficiency of chemotherapy), and remains to be studied in larger cohorts [29].…”

Merkel cell carcinoma-A rare primary neuroendocrine skin tumor: Case report and discussion

“…RT alone can be used as a palliative treatment with good control of primary and LN mets. [9] Chemotherapy has been performed with protocols based largely on agents active in small cell lung carcinoma. No chemotherapeutic protocol has, however, been able to achieve a significant increase in survival rate.…”