BAP1 Syndrome - Predisposition to Malignant Mesothelioma, Skin and Uveal Melanoma, Renal and Other Cancers.

BACKGROUND: BAP1 syndrome is an autosomal dominant hereditary cancer syndrome associated with increased risk of malignant mesothelioma; uveal and cutaneous melanoma; kidney cancer; lung adenocarcinoma; meningioma; basaliomas; and breast, ovarian, and prostate tumors. The BAP1 gene (BRCA1-associated protein 1) is a tumor suppressor gene involved in DNA repair via homologous recombination. BAP1 regulates the cell cycle, differentiation, DNA damage responses, and cell proliferation through deubiquitination. Somatic mutations in the BAP1 gene are common in many types of tumors. OBSERVATION: Two families harboring a germline mutation in the BAP1 gene were diagnosed at Masaryk Memorial Cancer Institute (MMCI). A 27-year-old index female from one family was followed-up for multiple nevi. Her mother and uncle had malignant mesothelioma, and her maternal grandmother had uveal melanoma. The index case tested positive for a BAP1 (NM_004656.2): c.217delG/p.Asp73Metfs*5 frame-shift mutation. The melanoma was removed at the age of 28 and 31. In the second family, an 11-year-old index female had two nevi removed from her head, and a spitzoid-type skin lesion was diagnosed at the age of 11. Her 34-year-old mother had multiple nevi, and a skin lesion of spitzoid-type was removed from the abdomen. Both patients harbored a BAP1 (NM_004656.2): c.123-1G>T acceptor splice site mutation (IARC [International Agency for Research on Cancer] class 4 [probably pathogenic]). Preventive measures for BAP1 syndrome should include known risks for cancer. Tumors occur early and repeatedly. At the MMCI, we recommend physical examination by an oncologist, eyes and skin examination, every 6 months; whole-body magnetic resonance imaging, including the central nervous system, every year (or low-dose computed tomography/chest and abdomen magnetic resonance imaging); annual abdominal ultrasound, breast ultrasound, or mammography; a gynecological ultrasound examination every 6 months; colonoscopy starting at the age of 45; and other suitable surveillances based on family history. CONCLUSION: BAP1 syndrome is a complex cancer syndrome with a high risk of rare malignant mesothelioma, malignant skin and uveal melanoma, spitzoid-type skin lesions, and other tumors. Detection of this syndrome is essential for the survival of high-risk individuals. Supported by the grant project MH CZ - RVO (MMCI, 00209805). The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. Submitted: 21. 5. 2019 Accepted: 6. 6. 2019.

A simple model to assess the probability of invasion in ductal carcinoma in situ of the breast diagnosed by needle biopsy.

OBJECTIVES: The aim of the study was to develop a clinical prediction model for assessing the probability of having invasive cancer in the definitive surgical resection specimen in patients with biopsy diagnosis of ductal carcinoma in situ (DCIS) of the breast, to facilitate decision making regarding axillary surgery. METHODS: In 349 women with DCIS, predictors of invasion in the definitive resection specimen were identified. A model to predict the probability of invasion was developed and subsequently simplified to divide patients into two risk categories. The model's performance was validated on another patient population. RESULTS: Multivariate logistic regression revealed four independent predictors of invasion: (i) suspicious (micro)invasion in the biopsy specimen; (ii) visibility of the lesion on ultrasonography; (iii) size of the lesion on mammography>30 mm; (iv) clinical palpability of the lesion. The actual frequency of invasion in the high-risk patient group in the test and validation population was 52.6% and 48.3%, respectively; in the low-risk group it was 16.8% and 7.1%, respectively. CONCLUSION: The model proved to have good performance. In patients with a low probability of invasion, an axillary procedure can be omitted without a substantial risk of additional surgery.