Clinical Course, Genetic, and Immunohistochemical Characterization of Solid Pseudopapillary Tumor of the Pancreas (Frantz Tumors) in a Brazilian Cohort.

Frantz tumors or solid pseudopapillary pancreatic neoplasm (SPN) are rare exocrine neoplasms that carry a favorable prognosis; they represent up to 3% of all tumors located in the region of the pancreas and have specific age and gender predispositions. In recent years, the rising curve of diagnosis is entitled to the evolution and access of diagnostic imaging. In this paper, we have retrospectively reviewed and described the clinical course of 40 patients with SPN from three institutions in Brazil, who had their diagnosis between 2005 and 2020, and analyzed the clinicopathological, genetic, and surgical aspects of these individuals. In accordance with the literature, most patients were women, 60% with unspecified symptoms at diagnosis, with tumors mainly located in the body and tail of the pancreas, of whom 70% underwent a distal pancreatectomy with sparing splenectomy as a standard procedure, and none of the cases have experienced recurrence to date. Surgery still remains the mainstay of treatment given the low metastatic potential, but more conservative approaches as observed in this cohort are evolving to become the standard of care. Herein, we present an in-depth analysis of cases focusing on the latest literature and report some of the smallest tumor cases in the literature. To our knowledge, this is the first report evaluating germline genetic testing and presenting a case of detected Li-Fraumeni syndrome.

Response to Pembrolizumab in Advanced Anal Squamous Cell Carcinoma With High TMB and PD-L1 and PD-L2 Amplification.

We report the case of a 44-year-old female with a prior diagnosis of Sjögren's syndrome who was treated for metastatic anal squamous cell carcinoma with second-line pembrolizumab and has achieved a sustained partial response after a follow-up of 13 months. Comprehensive genomic profiling was remarkable for PD-L1 and PD-L2 amplification and a high tumor mutational burden (19 mutations per megabase). To the best of our knowledge, we present the first report to correlate PD-L1 and PD-L2 amplification with good outcomes of immune checkpoint inhibition in metastatic anal squamous cell carcinoma.