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BACKGROUND: Merkel cell carcinoma (MCC) is a rare neuroendocrine skin cancer with poor 5-year survival rates. Surgery and radiation are the current first-line treatments for local and nodal disease. OBJECTIVES: The Brazilian Society of Surgical Oncology developed this document aiming to guide the surgical oncology role in multimodal MCC management. METHODS: The consensus was established in three rounds of online discussion, achieving consensus on specific topics including diagnosis, staging, treatment, and follow-up. RESULTS: Patients suspected of having MCC should undergo immunohistochemical examination and preferably undergo pathology review by a dermatopathologist. Initial staging should be performed with dermatologic and nodal physical examination, combined with complementary imaging. Whole-body imaging, preferably with positron emission tomography (PET) or computed tomography (CT) scans, are recommended. Due to the need for multidisciplinary approaches, we recommend that all cases should be discussed in tumor boards and referred to other specialties as soon as possible, reducing potential treatment delays. We recommend that all patients with clinical stage I or II may undergo local excision associated with sentinel lymph node biopsy. The decision on margin size should consider time to recovery, patient's comorbidities, and risk factors. Patients with positive sentinel lymph nodes or the presence of risk factors should undergo postoperative radiation therapy at the primary site. Exclusive radiation is a viable option for patients with low performance. Patients with positive sentinel lymph node biopsy should undergo nodal radiation therapy or lymphadenectomy. In patients with nodal clinical disease, in addition to primary tumor treatment, nodal radiation therapy and/or lymphadenectomy are recommended. Patients with advanced disease should preferably be enrolled in clinical trials and discussed in multidisciplinary meetings. The role of surgery and radiation therapy in the metastatic/advanced setting should be discussed individually and always in tumor boards. CONCLUSION: This document aims to standardize a protocol for initial assessment and treatment for Merkel cell carcinoma, optimizing oncologic outcomes in middle-income countries such as Brazil.

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OBJECTIVE: To evaluate the imaging findings of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) and computed tomography (CT) in patients with additional primary tumors, correlating the results with those of the method used in order to elucidate the diagnosis and of the pathology reports. MATERIALS AND METHODS: We retrospectively analyzed the medical records, pathology reports and images of 11 patients who underwent CT, 18F-FDG PET/CT, or both. We included patients with at least two tumors, with confirmed distinct histopathological profiles, at different sites. Patients in whom there was no diagnostic confirmation were excluded, as were those in whom the additional lesion was suspected of being a metastasis of the first. RESULTS: New primary malignancies were identified in 11 patients, one new tumor being found in 10 and two new tumors being found in 1. The confirmed sites of the additional malignancies were the lung, kidney, prostate, jejunum, and breast. Single or multiple percutaneous biopsies were performed in 10 patients, and 1 patient underwent a surgical procedure for diagnostic and therapeutic purposes. The tumors were metachronous in 6 cases and synchronous in 5. CONCLUSION: CT and 18F-FDG PET-CT combined with multiple percutaneous biopsy could facilitate the diagnosis of additional lesions, thus optimizing the treatment and follow-up of the affected patients.

OBJETIVO: Avaliar os achados de imagem da tomografia computadorizada por emissão de pósitrons com 18F-fluordesoxiglicose (18F-FDG PET/TC) e tomografia computadorizada (TC) em pacientes portadores de tumores primários adicionais, correlacionando com o método realizado para elucidação do diagnóstico e relatórios anatomopatológicos. MATERIAIS E MÉTODOS: Avaliamos, retrospectivamente, prontuários, relatórios anatomopatológicos e exames de 11 pacientes que realizaram 18F-FDG PET/TC e/ou TC. Foram incluídos pacientes que apresentaram pelo menos duas neoplasias, com histopatologia distinta confirmada nos diferentes locais. Foram excluídos pacientes sem confirmação diagnóstica e pacientes com suspeita de que a lesão adicional fosse uma metástase da primeira. RESULTADOS: Lesões sugestivas de novas malignidades primárias foram encontradas em 11 pacientes, apresentando em 10 deles uma única nova lesão e em 1 caso dois novos tumores. Locais comprovados de lesão adicional foram pulmão, rim, próstata, jejuno e mama. Biópsia percutânea única ou múltipla foi realizada em 10 pacientes e 1 paciente foi submetido a procedimento cirúrgico para fins diagnósticos e terapêuticos. Os tumores eram metacrônicos em 6 casos e sincrônicos em 5 pacientes. CONCLUSÃO: A TC e a 18F-FDG PET/TC associadas a biópsias percutâneas múltiplas podem auxiliar no diagnóstico de lesões adicionais, otimizando o tratamento e acompanhamento desses pacientes.