Multidisciplinary Approaches to Managing Merkel Cell Carcinoma
Posted: Wednesday, July 22, 2020
Management of Merkel cell carcinoma should revolve around the approaches of a multidisciplinary team, according to a commentary in Frontiers in Oncology. Simone Mocellin, MD, PhD, of the University of Padua, Italy, and colleagues conducted a literature review and proposed a clinical approach to diagnosing and treating patients with Merkel cell carcinoma.
The authors recommended that histologic and immunohistochemical analysis be performed first to confirm the diagnosis of Merkel cell carcinoma. Although there are numerous well-defined epithelial markers, the current literature suggests that insulinoma-associated protein 1 (INSM1) may prove to be a useful neuroendocrine marker to confirm a diagnosis.
After diagnosis, patients should undergo a sentinel lymph node biopsy (SLNB) to stage their cancer and determine their prognosis. A positive SLNB result suggests the need for complete lymph node resection. In addition, imaging should be performed to stage the tumor and formulate a plan for surgical intervention. The investigators found that total-body 18 F-FDG-PET with thoracic and abdominal CT scans has shown benefit in both staging and monitoring for recurrence.
Regarding treatment, for patients with primary tumors, surgical intervention with wide excision of either 1 cm for T1 tumors or 2 cm for T2–T4 tumors and postoperative adjuvant radiation therapy are usually recommended. However, the authors stressed the importance of utilizing the multidisciplinary team to assess the best possible outcome for patients before surgery. For those with regional lymph nodes, evaluation should be the first step to determine the course of treatment. Patients with clinically positive lymph nodes should receive complete regional lymph node dissection and/or regional radiotherapy, whereas patients with clinically negative lymph nodes should consider SLNB as their next step. Moreover, additional emerging treatment strategies including immunotherapy and targeted therapy may be potential therapeutic options for patients with Merkel cell carcinoma.
Disclosure: The study authors reported no conflicts of interest.