Moving the needle.

Margin-negative resection is the key treatment for localized Merkel cell carcinoma (MCC), with adjuvant radiation—not chemo—serving to reduce the risk of locoregional recurrence. Recently, immune checkpoint inhibitors have established a role in the treatment of advanced and metastatic MCC. This cohort study of the CheckMate 358 trial gave just 2 cycles of neoadjuvant nivolumab to patients with resectable MCC, which included de novo tumors that were ≥2 cm, node-positive, or oligometastatic, as well as ≥1 cm locoregional recurrences. The majority of patients (>60%) had node-positive disease that was Merkel cell polyoma virus (MCPyV) positive. 17 of 36 patients who underwent surgery, or a whopping 47%, had a pathologic complete response (pCR) with another 15% achieving a major pathologic response. The study was small, but no patient with pCR has had a tumor recurrence at a median follow-up of >20 months. TBL: Neoadjuvant nivolumab has a nearly 50% pCR rate for resectable MCC. | Topalian, J Clin Oncol 2020