Nivolumab induced pulmonary sarcoid-like granulomas with a concurrent pleural schwannoma: A pathologic-radiologic correlation of a rare condition mimicking metastatic melanoma.

Nivolumab is an anti-PD-1 antibody. The mechanism of action of nivolumab is inhibition of binding between PD-1 and PD-1 ligand. This causes activation of antigen-specific T cells that were previously unresponsive to cancer cells. This unique mechanism of action attributes the widespread use of nivolumab for the treatment of a variety of neoplastic conditions. On the other hand, this mode of action is associated with adverse effects as well. Schwannoma, also called neurilemmoma, is a benign peripheral nerve sheath tumor. Pleural schwannomas are very rare and very few cases have been reported in the medical English literature so far. Herein, we report a very rare case of concurrent presence of Nivolumab induced pulmonary sarcoid-like granulomas along with primary benign pleural schwannoma in a 49-year-old male. He was diagnosed with malignant melanoma of the right upper arm for which he underwent surgery and was receiving adjuvant chemotherapy. He developed pneumonitis during chemotherapy, and on imaging multiple reticular and nodular interstitial infiltrates were seen along with an incidental pleural mass with a high suspicion for metastasis. Wedge biopsy of the interstitial infiltrates was done and they were found to be pulmonary granulomas related to the nivolumab therapy he was receiving. The patient underwent excision of the pleural mass which showed histopathological and immunohistochemical features of schwannoma. The two conditions are unrelated and rarely encountered simultaneously. The radiologic and pathologic correlation along with differential diagnosis of these conditions are discussed.

Feasibility of a truncated surveillance schedule for patients following curative intent treatment for carcinoma of the oral cavity.

The purpose of this study was to determine whether a regular follow-up schedule with examination by clinicians results in a better detection rate of disease recurrence and eventual better clinical outcomes when compared to patients who present with symptoms to the clinic and are subsequently detected to have a recurrence of oral squamous cell carcinoma. Retrospective data from 642 patients who underwent treatment for oral squamous cell carcinoma at a tertiary level cancer centre were analysed. Of the 642 patients, 197 had recurrences of which 108 were detected on regular follow-up and 87 were detected in patients presenting out of schedule with symptoms; two patients were detected to have recurrence at another centre, but their mode of detection could not be ascertained. There was no difference in the loco-regional recurrence-free survival or disease-free survival between the two groups. A strict follow-up schedule in the first year followed by a more flexible symptom-based schedule in the subsequent years, with supplementation of imaging if clinically indicated, should be an adequate surveillance plan for oral cancer patients.