{"entity":{"id":"medullary-pattern-breast-carcinoma","kind":"cancer","name":"Carcinoma with medullary pattern (medullary breast cancer)","aka":["Medullary carcinoma of the breast","Medullary breast cancer","Invasive carcinoma of no special type with medullary pattern","Atypical medullary carcinoma","Basal-like carcinoma with medullary features"],"tldr":"Medullary breast cancers are high-grade, triple-negative tumours with a sharp border and a heavy immune-cell infiltrate that, despite looking aggressive, do better than ordinary breast cancers of the same grade. They are linked to BRCA1. Pathologists now call them a medullary pattern of common breast cancer rather than a type of their own.","summary":"Medullary carcinoma was defined by a circumscribed, syncytial growth pattern, high nuclear grade and a dense lymphoplasmacytic infiltrate; because pathologists agreed poorly on the diagnosis and the molecular profile overlaps basal-like carcinoma, the 5th edition of the WHO classification (2019) reclassified it as invasive breast carcinoma of no special type with medullary pattern, alongside the other patterns of common ductal-origin carcinoma (Cserni 2020; Thomas 2023). Its behaviour is better than its grade suggests: among 12,409 patients in 13 International Breast Cancer Study Group trials, 14-year distant recurrence-free interval was 76 percent for 127 medullary against 64 percent for 8,096 invasive ductal tumours (hazard ratio 0.52) and overall survival 66 against 57 percent (0.75); restricted to ER-negative grade 3 tumours the figures were 89 against 63 percent (0.24) and 74 against 54 percent (0.55) (Huober 2012). Medullary tumours are BRCA1-related (odds ratio for BRCA2 versus BRCA1 carrier status 0.25 in the CIMBA pathology series, Mavaddat 2012), and the claudin-low subtype shows frequent medullary differentiation (Prat 2010). The immune infiltrate is the same feature now scored as stromal tumour-infiltrating lymphocytes across triple-negative disease.","asOf":"2026-09-24","wikipedia":"https://en.wikipedia.org/wiki/Medullary_breast_carcinoma","links":[{"label":"Huober, Ann Oncol 2012: prognosis of medullary breast cancer in 13 IBCSG trials","url":"https://doi.org/10.1093/annonc/mds105"},{"label":"Cserni, Pathologica 2020: histological type and typing of breast carcinomas and WHO classification changes","url":"https://doi.org/10.32074/1591-951x-1-20"},{"label":"Thomas, NPJ Breast Cancer 2023: rare subtypes of triple-negative breast cancer","url":"https://doi.org/10.1038/s41523-023-00554-x"},{"label":"Mavaddat, Cancer Epidemiol Biomarkers Prev 2012: pathology of breast cancers in BRCA1 and BRCA2 carriers (CIMBA)","url":"https://doi.org/10.1158/1055-9965.epi-11-0775"},{"label":"Prat, Breast Cancer Res 2010: phenotypic and molecular characterisation of the claudin-low intrinsic subtype","url":"https://doi.org/10.1186/bcr2635"}],"tags":["breast","tnbc","subtype-page"],"related":["tnbc","brca-associated-tnbc","tnbc-immunomodulatory","metaplastic-breast-carcinoma"],"cancers":[],"sections":[],"technologies":[],"targets":["brca"],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":["tils","basal-like","germline-brca-testing-criteria-tnbc"],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"group":"breast","burden":"About 1 percent of breast cancers in trial populations: 127 of 12,409 patients in 13 IBCSG trials were recorded as medullary (Huober 2012). The 2019 WHO classification no longer lists it as a separate type.","subtypes":["Invasive carcinoma of no special type (ductal) with medullary pattern, the 2019 WHO term","Classic medullary carcinoma by the older strict criteria","Atypical medullary carcinoma (older term for tumours meeting some criteria)"],"biomarkers":["Triple-negative receptor status with grade 3","Dense lymphoplasmacytic infiltrate (high stromal tumour-infiltrating lymphocytes)","Germline BRCA1 (medullary tumours are BRCA1-related)"],"standardOfCare":[{"setting":"Early disease","approach":"As for triple-negative disease of no special type, including germline testing; the medullary pattern is recorded because of its better prognosis but does not change the NICE pathway.","refs":["keynote-522","germline-testing","tils"]}],"stateOfArt":[],"history":[],"pipeline":[],"openProblems":[],"parent":"tnbc"},"route":"/cancers/medullary-pattern-breast-carcinoma/","neighbours":{"cancer":[{"id":"brca-associated-tnbc","kind":"cancer","name":"BRCA-associated triple-negative breast cancer","route":"/cancers/brca-associated-tnbc/"},{"id":"tnbc-immunomodulatory","kind":"cancer","name":"Immunomodulatory triple-negative breast cancer (IM)","route":"/cancers/tnbc-immunomodulatory/"},{"id":"metaplastic-breast-carcinoma","kind":"cancer","name":"Metaplastic breast carcinoma","route":"/cancers/metaplastic-breast-carcinoma/"},{"id":"tnbc","kind":"cancer","name":"Triple-negative breast cancer (TNBC)","route":"/cancers/tnbc/"}],"target":[{"id":"brca","kind":"target","name":"BRCA1 / BRCA2 (HRD)","route":"/targets/brca/"}],"term":[{"id":"basal-like","kind":"term","name":"Basal-like breast cancer","route":"/terms/basal-like/"},{"id":"germline-brca-testing-criteria-tnbc","kind":"term","name":"Germline BRCA testing criteria for triple-negative breast cancer (UK)","route":"/terms/germline-brca-testing-criteria-tnbc/"},{"id":"tils","kind":"term","name":"Tumour-infiltrating lymphocytes (TILs)","route":"/terms/tils/"}],"trial":[{"id":"keynote-522","kind":"trial","name":"KEYNOTE-522","route":"/trials/keynote-522/"}],"technology":[{"id":"germline-testing","kind":"technology","name":"Germline (hereditary) testing","route":"/technologies/germline-testing/"}]}}