Search

Objective: We evaluated vessel counts in the pharyngeal mucosal margins of patients who underwent salvage laryngectomy to establish whether mucosal vascularity might predict fistula risk. Study Design: Retrospective cohort. Setting: Tertiary Medical Center. Methods: Patients who underwent salvage total laryngectomy at our institution between 1999 and 2015 were identified. Pharyngeal mucosal margins from laryngectomy specimens were evaluated histologically for each patient, and vessel counts were performed on 5 ×10 images. The primary outcome measure was fistula within 30 days of surgery and mean vessel counts were assessed as the principle explanatory variable. Results: Seventy patients were included and 40% developed a postoperative fistula. There was a large difference in the mean vessel count in patients who did develop fistula (48.6 vessels/×10 field) compared to those who did not (34.7 vessels/×10 field). A receiver operative characteristic curve found that a cutoff value of 33.9 vessels/×10 field provided a sensitivity of 75% and specificity of 62% to predict the likelihood of fistula occurrence (area under the curve = 0.71, 95% confidence interval [CI]: 0.59‐0.83). In a binary logistic regression, patients with vessel counts greater than 33.9 had a 5‐fold increased risk of developing fistula (95% CI: 1.8‐16.45). Histologically, vessels in the pharyngeal mucosa of patients who developed fistulas were more disorganized. Conclusion: After salvage laryngectomy, patients with higher mean mucosal margin vessel counts are at increased risk of fistula. The mechanism is unknown, but the disorganization of the vasculature may contribute to poor wound healing. Vessel counting may allow for fistula risk stratification and guide postoperative care. [ABSTRACT FROM AUTHOR]

Mucoepidermoid Carcinoma (MEC) is a common salivary malignant neoplasm. Approximately 60 % of MECs harbor translocations between CRTC1 or CRTC3 and MAML2, which are thought to drive disease pathogenesis. However, the precise structural mechanism driving this rearrangement remains uncharacterized. Here, we performed multi-omic and long read genomic sequencing, discovering a chain of alterations that created the CRTC1::MAML2 fusion, but also an unexpected MAML2 to MYBL1 rearrangement, suggesting that MYBL1 may play a larger role in salivary gland cancers than previously recognized. Furthermore, we discovered and validated recurrent TERT rearrangements and amplifications in MEC models. 5/5 MEC cell lines and 36/39 (92 %) primary MEC tumors harbored a TERT rearrangement or copy number amplification. Custom sequencing of the TERT locus confirmed translocation breakpoints in 13/33 (39 %) MECs, while exome sequencing confirmed frequent TERT amplifications. Critically, TERT knockdown in NCI-H292, a cell line with TERT promoter rearrangement, reduced clonogenic cell survival, supporting a critical role of this gene in MEC tumorigenesis. Overall, our data suggest that complex chromothripsis rearrangement mechanisms drive the formation of structural variation in CRTC1::MAML2 fusion positive and negative tumors and reveal highly recurrent structural variation driving TERT rearrangement in MEC., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)