Lentigo maligna (LM) is a melanoma in situ and the incidence is still rising in The Netherlands. LM is mostly located in the face, therefore radical surgical removal, which is the first choice of treatment, can be challenging in this delicate anatomical region. Staged excision is considered a useful alternative. The initial diagnosis of clinically suspicious LM is usually based on just one or a few biopsies, which may lead to reclassification into lentigo maligna melanoma (LMM) based on histological evaluation of the excision specimen. This article is protected by copyright. All rights reserved.

Abstract Background/purpose: To determine the efficacy and toxicity profile of a stereotactic body radiotherapy (SBRT) boost as a first line treatment in patients with oropharyngeal squamous cell carcinoma (OPSCC). Materials and methods: We performed a retrospective cohort study in 195 consecutive OPSCC patients with T1-small T3 disease, treated at Erasmus MC between 2009 and 2016 with a SBRT (3 × 5.5 Gy) boost after 46 Gy IMRT. Primary endpoints were disease-specific survival (DSS) and Grade ≥3 toxicity (Common Terminology Criteria). The Kaplan-Meier method and Cox regression model were applied to determine rates and risk factors. Results: The median follow-up was 4.3 years. Treatment compliance was high (100%). Rates of 5-year DSS and late grade ≥3 toxicity were 85% and 28%, respectively. Five-year overall survival was 67%. The most frequently observed toxicities were mucosal ulceration or soft tissue necrosis (n = 30, 5 year 18%), dysphagia or weight loss (n = 18, 5 year 12%) and osteoradionecrosis (n = 11, 5 year 9%). Current smoker status (hazard ratio [HR] = 2.9, p = .001) and Charlson Comorbidity Index ≥2 (HR = 1.9, p = .03) were was associated with increased toxicity risk. Tooth extraction prior to RT was associated with increased osteoradionecrosis risk (HR = 6.4, p = .006). Conclusion: We reported on outcomes in the largest patient series to date treated with a hypofractionated boost for OPSCC. Efficacy was good with survival rates comparable to conventionally fractionated (chemo)radiotherapy. Grade ≥3 toxicity profiles showed high rates of soft tissue necrosis and osteoradionecrosis. Strategies to mitigate severe toxicity risks are under investigation to improve the tolerability of the SBRT boost.

Specimen‐driven intraoperative assessment of the resection margins provides immediate feedback if an additional excision is needed. However, relocation of an inadequate margin in the wound bed has shown to be difficult. The objective of this study is to assess a reliable method for accurate relocation of inadequate tumor resection margins in the wound bed after intraoperative assessment of the specimen.

Background: One significant risk factor for recurrence after Mohs micrographic surgery (MMS) is misinterpretation of slides. Objectives: To determine how often pathologists detected incompletely excised basal cell carcinoma (BCC) on MMS slides and to determine risk factors for incompletely excised BCCs. Methods: This retrospective study included 1,653 BCCs treated with MMS in a university hospital between 2007 and 2011. For routine quality assurance, all slides were additionally reviewed by a pathologist within one week of the procedure. For this study, all cases that had divergent interpretations were re-evaluated by a MMS surgeon and a pathologist. Mixed-effects logistic regression models with MMS surgeon effects as random effects were used to determine risk factors for incompletely excised BCC. Results: Incompletely excised BCCs were detected in 2% (31/1,653), in which defects > 20 mm in diameter were an independent risk factor (OR 3.6, 95% CI 1.6-8.3). Other studied variables (i.e. aggressive subtype, previously treated BCC, location on nose and > 2 MMS stages) did not affect the risk of incompletely excised BCCs. Conclusions: The additional review of MM slides might increase accurate interpretation, especially in large BCCs. 2 Erasmus Medical Center Rotterdam

This study aimed to analyze the effect of human papillomavirus (HPV)‐associated T1‐2 node‐positive oropharyngeal squamous cell carcinoma (OPSCC) on nodal response, recurrent disease, and survival in patients treated according to the Rotterdam protocol.

A Raman tissue spectrum is a quantitative representation of the overall molecular composition of that tissue. Raman spectra are often used as tissue fingerprints without further interpretation of the specific information that they contain about the tissue's molecular composition. In this study, we analyzed the differences in molecular composition between oral cavity squamous cell carcinoma (OCSCC) and healthy tissue structures in tongue, based on their Raman spectra. A total of 1087 histopathologically annotated spectra (142 OCSCC, 202 surface squamous epithelium, 61 muscle, 65 adipose tissue, 581 connective tissue, 26 gland, and 10 nerve) were obtained from Raman maps of 44 tongue samples from 21 patients. A characteristic, average spectrum of each tissue structure was fitted with a set of 55 pure-compound reference spectra, to define the best library of fit-spectra. Reference spectra represented proteins, lipids, nucleic acids, carbohydrates, amino acids and other miscellaneous molecules. A non-negative least-squares algorithm was used for fitting. Individual spectra per histopathological annotation were then fitted with this selected library in order to determine the molecular composition per tissue structure. The spectral contribution per chemical class was calculated. The results show that all characteristic tissue-type spectra could be fitted with a low residual of <4.82%. The content of carbohydrates, proteins and amino acids was the strongest discriminator between OCSCC and healthy tissue. The combination of carbohydrates, proteins and amino acids was used for a classification model of 'tumor' versus 'healthy tissue'. Validation of this model on an independent dataset showed a specificity of 93% at a sensitivity of 100%.

Nasopharyngeal carcinoma (NPC) treatment is mainly based on clinical staging. We hypothesize that better understanding of the molecular heterogeneity of NPC can aid in better treatment decisions. Therefore, the purpose of this study was to present our exploration of cancer gene copy‐number alterations (CNAs) of Epstein‐Barr virus (EBV)‐positive and EBV‐negative NPC.