Aim
Merkel Cell Carcinoma (MCC) is a rare, aggressive and highly metastatic neuroendocrine tumour of the skin. Role of adjuvant chemotherapy is controversial in early stage MCC.
Methods
A retrospective review of electronic and paper medical records was conducted of patients with MCC localised to primary cutaneous (PC) site and lymph nodes treated with radiotherapy (RT) or chemoradiotherapy (CRT) with weekly carboplatin (AUC 2) followed by 3 cycles of adjuvant chemotherapy (CT) with carboplatin and etoposide at our institution between 2008 and 2013.
Results
17 patients identified of whom 12 completed the entire protocol. Of these 12, 75% were male, 50% ex-smokers; with median age 69 years (48-84), predominantly stage III of which -18% presented with PC site and 82% with an unknown primary (UP) site involving nodal basin (cervical/parotid 67%, axillary 11%, and inguinal 22%). Patients presenting with PC sites involving upper limb, lower limb and trunk were 1, 1, and 1 respectively. Median size of PC site was 2.9 cm (0.9-6). 5 patients (42%) underwent complete lymph node dissection (LND); 2 had LND followed by RT then adjuvant CT, 3 had LND followed by CRT then adjuvant CT. Definitive CRT followed by adjuvant CT was provided to 6 (50%) patients; 1 patient had primary resected but regional lymph node (LN) was unresectable and 1 patient had unresectable primary. 67% achieved complete radiologic response and 33% had partial response. 1 patient had primary with one positive sentinel lymph node resected and received CRT followed by adjuvant CT.
Complications were generally minimal. Median time to progression 10.3 months (6–16). Median overall survival 22.6 months (15-35), however, 75% of patients remain disease free on follow up.
Conclusion
In our practice multimodality approach was well tolerated and resulted in better outcomes.
The above data are significant to clinical management of patients presenting with this rare cancer subtype.