Paraganglioma of the Head and Neck: A Review.

OBJECTIVE: To review the epidemiology, presentation, diagnosis, and management of head and neck paragangliomas. METHODS: A literature review of english language papers with focus on most current literature. RESULTS: Paragangliomas (PGLs) are a group of neuroendocrine tumors that arise in the parasympathetic or sympathetic ganglia. Head and neck PGLs (HNPGLs) comprise 65% to 70% of all PGLs and account for 0.6% of all head and neck cancers. The majority of HNPGLs are benign, and 6% to 19% of all HNPGLs develop metastasis outside the tumor site and significantly compromise survival. PGLs can have a familial etiology with germline sequence variations in different susceptibility genes, with the gene encoding succinate dehydrogenase being the most common sequence variation, or they can arise from somatic sequence variations or fusion genes. Workup includes biochemical testing to rule out secretory components, although it is rare in HNPGLs. In addition, imaging modalities, such as computed tomography and magnetic resonance imaging, help in monitoring in surgical planning. Functional imaging with DOTATATE-positron emission tomography, 18F-fluorodeoxyglucose, or 18F-fluorohydroxyphenylalanine may be necessary to rule out sites of metastases. The management of HNPGLs is complex depending on pathology, location, and aggressiveness of the tumor. Treatment ranges from observation to resection to systemic treatment. Similarly, the prognosis ranges from a normal life expectancy to a 5-year survival of 11.8% in patients with distant metastasis. CONCLUSION: Our review is a comprehensive summary of the incidence, mortality, pathogenesis, presentation, workup and management of HNPGLs.

Avapritinib treatment of aggressive systemic mastocytosis with a novel KIT exon 17 mutation.

Background: Systemic mastocytosis is a rare hematologic malignancy that leads to the accumulation of neoplastic mast cells in the bone marrow, visceral organs, and skin. Mutations in the receptor tyrosine kinase, KIT are seen in most patients with systemic mastocytosis. The most common mutation is a gain of function mutation in KIT D816V. Avapritinib is a highly selective KIT D816V inhibitor approved for the treatment of advanced systemic mastocytosis. Recent studies have also suggested that avapritinib is active across other KIT mutations located in exon 11 and exon 17. Case Presentation: A 68 year old woman was referred for a history of lymphadenopathy and diarrhea and was ultimately found to have systemic mastocytosis with involvement in her bone marrow, gastrointestinal tract, liver, and spleen. The bone marrow biopsy reveled a novel KIT p.D816-N822delinsMIDSI mutation in exon 17. The patient was started on avapritinib leading to significant decrease in the frequency of her diarrhea and a significant reduction in her tryptase levels. Her course was complicated by arthralgias leading to a decrease in her avapritinib dose and ultimately a degranulation episode requiring hospitalization. Following dose re-escalation, patient has remained clinically stable without any further adverse events. Conclusion: We report a case of aggressive systemic mastocytosis with a novel KIT mutation on exon 17 treated with avapritinib leading to a sustained response. While avapritinib is known as a potent inhibitor against the D816V mutation, our case suggests that it may also be effective against other rare KIT mutations in systemic mastocytosis offering more potential treatment options in patients with rare mutations.

Treatment of BRAF V600E mutant gastrointestinal stromal tumor with dabrafenib: a case report.

Background: Gastrointestinal stromal tumor (GIST) is a rare mesenchymal tumor arising in the gut, most commonly stomach or small bowel. The most common driver mutations are KIT and PDGFRA which can be treated with imatinib or avapritinib (for PDGFRA D842V-mutant GIST), respectively. BRAF V600E mutant GISTs are rare and these do not respond to imatinib. Multiple clinical trials have shown antitumor effects with dabrafenib in BRAF-mutant melanoma and a few case reports have demonstrated treatment of BRAF V600E mutant GIST with a BRAF kinase inhibitor. Case Description: We present a case of a 67-year-old woman diagnosed with high-risk GIST following initial resection. She was initially treated with adjuvant imatinib which was discontinued after 7 months because molecular analysis of her tumor showed the absence of KIT and PDGFRA mutations and a BRAF V600E mutation. When her disease progressed, she was started on sunitinib and subsequently regorafenib. Both agents were discontinued due to severe palmar-plantar erythrodysesthesia and clinical progression. She was subsequently started on dabrafenib based on the presence of a BRAF V600E mutation; this therapy led to a partial response. Her disease remained stable on this medication for 19 months before progression and addition of trametinib to her treatment. Her disease continued to progress and she was switched to everolimus with mixed response before re-challenging with dabrafenib and trametinib. Her imaging showed a mixed response to the re-challenge before progressing after 5 months and transitioning to hospice. Conclusions: We describe an uncommon molecular subtype of GIST with a BRAF V600E mutation. As expected, her disease was resistant to standard GIST therapy, however there was notable tumor regression following treatment with dabrafenib. This case shows the importance of molecular testing in GIST and adds to the current body of literature on the treatment of BRAF-mutant GIST.

Survival in metastatic microsatellite-stable colorectal cancer correlated with tumor mutation burden and mutations identified by next-generation sequencing.

Background: Next-generation sequencing (NGS) identifies mutations and molecular abnormalities within tumors, including tumor mutation burden (TMB). If a solid tumor has high TMB, immune checkpoint inhibitors (ICIs) are approved as an option for treatment. Studies have been inconclusive regarding how effective ICI are in treating patients with colorectal cancer (CRC), and it is unclear if high TMB is a good prognostic marker for CRC. We collected data from NGS of CRC and correlated survival to both TMB and mutations of interest, as well as investigated the efficacy of ICI. Methods: This was a retrospective cohort analysis at a single institution, collecting NGS data from January 2018 to December 2020 in patients with CRC who were microsatellite-stable (MSS), n=161. Demographics, clinical data, and results from NGS were collected, and a survival analysis looking at TMB and selected mutations of interest was performed. Patients who were treated with ICI were assessed in a descriptive subset analysis. Results: Patients with CRC who were MSS and had high TMB trended towards worse survival [hazard ratio (HR) =1.38] though the result was not significant (P=0.28). Survival was significantly worse in patients with a KRAS mutation (HR =1.71, P=0.04) and/or a CDKN2A mutation (HR =4.45, P<0.001). In this study population, 12 patients with high TMB had treatment with ICI, with nine of these patients having shorter progression-free survival (PFS) between 0.7 and 4.1 months, and three patients having longer PFS of 26.3, 24.7, and 13.2 months. Conclusions: High TMB in MSS CRC did not show statistical difference in outcome. Mutations in KRAS and/or CDKN2A correlated with worse prognosis. Some patients with MSS CRC and high TMB responded to ICI, though there is a need to identify a better biomarker to predict which patients will have a good response to ICI therapy.

Avapritinib treatment of KIT D816V-mutant atypical chronic myeloid leukemia.

Background: Atypical chronic myeloid leukemia (aCML) is a rare myelodysplastic/myeloproliferative neoplasm. There is no proven standard of care treatment and the only curative option available is hematopoietic stem cell transplant. In addition to traditional chemotherapy, targeted therapy has shown to be a promising. Avapritinib is a selective type 1 tyrosine kinase inhibitor with high potency for KIT D816V and was recently approved for treatment of systemic mastocytosis. Here we present a case of aCML with novel D816V mutation treated with avapritinib for 17 months leading to clonal extinction of the driver mutation. Case presentation: An 80 year old man initially presented for evaluation of aCML. A bone marrow biopsy was completed, and next generation sequencing was notable for a novel KIT D816V mutation. Patient was started on avapritinib leading to significant improvement in leukocytosis and extinction of the D816V mutation over 17 months of treatment. The extinction was followed with serial next generation sequencing. Conclusion: We present the first case of aCML with KIT D816V driver mutation. We also demonstrate two novel management strategies. First, we show that treatment with avapritinib does not need to be limited to cases of systemic mastocytosis and could be useful in other hematologic malignancies with this driver mutation. Furthermore, with the use of serial next generation sequencing we were able to identify new emerging clones. While none of the clones noted in this study were targetable, they could be in other patients with aCML and help guide treatment.

The Clinical Applicability of Primary Thromboprophylaxis in Ambulatory Patients With Pancreatic Cancer.

ABSTRACT: Thromboembolism is a leading cause of death in ambulatory patients with cancer. Patients with pancreatic adenocarcinoma have a very high risk of developing venous thromboembolism, especially within the first 6 months of diagnosis. Although primary thromboprophylaxis could reduce this risk, there are unresolved questions concerning choice of agents for anticoagulation, duration of anticoagulation treatment, and criteria for patient selection. Furthermore, the current clinical guidelines on primary thromboprophylaxis in ambulatory patients with pancreatic cancer are ambiguous. This review seeks out to understand and critically appraise the evidence supporting the use of primary thromboprophylaxis in patients with pancreatic cancer and its clinical applicability.

The Use of Crowdfunding to Support Radiation Therapy Cancer Treatments.

BACKGROUND/AIM: The purpose of this study was to assess patients' use of a crowdfunding platform to raise funds for radiation treatment and to better understand the direct and indirect costs associated with treatments. MATERIALS AND METHODS: The GoFundMe crowdfunding database was queried for four unique categories related to radiation treatment campaigns. Covariates identified included clinical and demographic variables, and associations between amount raised and these predictors were analyzed using a generalized linear model. RESULTS: While 56% percent of campaigns cited direct costs associated with treatment, 73.4% of campaigns cited indirect costs related to treatment. Indirect expenses related to travel (31.7%) as well as living expenses (29.2%) were cited most often across all four treatment categories. CONCLUSION: This study enhances understanding regarding patients use of crowdfunding for radiation treatment. Increased focus should be placed on discussing the indirect costs of care with patients and their families.