Lynch syndrome: An unusal case of familial cancer unearthed

Lynch syndrome or hereditary nonpolyposis colorectal cancer (HNPCC) is a type of inherited cancer syndrome with a genetic predisposition to different types of cancer. There is an increased predisposition to cancers in the endometrium, colon, stomach, ovary, uterus, skin, kidney, and brain in patients of Lynch syndrome. We are reporting a 48-year-old male who presented with a pea-sized growth in his left arm which was found to be sebaceoma on histopathology. On further detailed history, examination, and genetic study, it was proved to be a familial case of Lynch syndrome. The case is being reported to stress the importance of knowledge about clinical manifestation, associated neoplasms, and molecular genetic profile of Lynch syndrome which will enable physicians and pathologists to provide highly targeted surveillance and management for patients with high cancer risk.

Historical review of Lynch syndrome / Revisão histórica da síndrome de Lynch

Lynch syndrome was formerly known as Hereditary Nonpolyposis Colorectal Cancer. Currently, these two nomenclatures each have their unique definitions and are no longer used interchangeably. The history of hereditary nonpolyposis colorectal cancer was first recognized formally in the literature by Henry Lynch in 1967. With advances of molecular genetics, there has been a transformation from clinical phenotype to genotype diagnostics. This has led to the ability to diagnose affected patients before they manifest with cancer, and therefore allow preventative surveillance strategies. Genotype diagnostics has shown a difference in penetrance of different cancer risks dependent on the gene containing the mutation. Surgery is recommended as prevention for some cancers; for others they are reserved for once cancer is noted. Various surveillance strategies are recommended dependent on the relative risk of cancer and the ability to intervene with surgery to impact on survival. Risk reduction through aspirin has shown some recent promise, and continues to be studied. (AU)

A síndrome de Lynch era anteriormente conhecida como "câncer colorretal hereditário não polipose". Atualmente, essas duas nomenclaturas têm, cada uma, sua própria definição original e já não são empregadas de forma intercambiável. O histórico de câncer colorretal hereditário não polipose foi formalmente reconhecido pela primeira vez na literatura por Henry Lynch em 1967. Com os avanços da genética molecular, verificou-se uma mudança do fenótipo clínico para o diagnóstico genotípico. Esse fato levou à capacidade de diagnosticar pacientes afetados antes que o câncer se manifestasse, e, portanto, à utilização de estratégias preventivas de rastreamento. O diagnóstico genotípico mostrou a diferença na penetrância de diferentes riscos de câncer dependendo do gene que contem a mutação. A cirurgia é recomendada para a prevenção de alguns tipos de câncer; para outros, ela é reservada quando há o aparecimento da doença. Várias estratégias de rastreamento são recomendadas, dependendo do risco relativo de câncer, bem como a capacidade para intervir com a cirurgia objetivando um impacto na sobrevivência. A redução do risco através do uso de aspirina recentemente mostrou ser promissor e continua a ser estudada. (AU)

Associations between BRCA Mutations in High-Risk Breast Cancer Patients and Familial Cancers Other than Breast or Ovary / 한국유방암학회지

PURPOSE: We investigated the relationship between BRCA mutations and the distribution of familial cancers other than breast or ovary in high-risk breast cancer patients. METHODS: Patients with breast cancer who had at least one of the following risk factors were enrolled: reported family history of breast or ovarian cancer; 40 years of age or younger age at diagnosis; bilateral breast cancer; or male gender. Genetic testing for BRCA mutation and questionnaires about personal and family histories of malignancies were performed. RESULTS: Among the 238 eligible patients, 49 (20.6%) patients had BRCA1/2 mutations, which were more frequent in patients with multiple risk factors (p<0.0001). There were 271 members of 156 (65.5%) families who had histories of other primary cancer. The distribution of the families was 119 (63.0%) and 37 (75.5%) in the BRCA-negative and positive group, respectively (p=0.0996). Multiple familial cancers occurred in 70 families, which were significantly more frequent in BRCA-positive families (p=0.0034). By ordinal logistic regression, the occurrence of multiple familial cancers was associated with BRCA mutations (p=0.0045), not with other risk factors. The most common site of disease was the stomach, which is the most common in nationwide. And the proportional incidence of pancreatic cancer (6.8%) was significantly higher than that of nationwide cancer statistics (2.4%, p=0.0137). CONCLUSION: BRCA mutations in high-risk breast cancer patients were associated with multiple risk factors and multiple family members with other primary cancers. Genetic counseling based on accurate information should be provided to families with BRCA mutation carriers.