{"entity":{"id":"tam-01","kind":"trial","name":"TAM-01","aka":[],"tldr":"TAM-01 showed that a quarter of the usual tamoxifen dose, taken for three years, roughly halved the risk of a new or recurrent breast cancer after treatment for DCIS or other pre-invasive changes, with far fewer of the side effects that make women stop the full dose.","summary":"Tamoxifen at 20 mg daily prevents recurrence after ductal carcinoma in situ but hot flushes, endometrial cancer and thrombosis limit its use. TAM-01 was an Italian phase 3 trial that randomised 500 women with breast intraepithelial neoplasia (atypical ductal hyperplasia, lobular carcinoma in situ or oestrogen receptor-positive or unknown ductal carcinoma in situ) to tamoxifen 5 mg daily or placebo for three years. The primary endpoint was the incidence of invasive breast cancer or ductal carcinoma in situ.\n\nLow-dose tamoxifen roughly halved the rate of breast events, including contralateral cancers, with no significant excess of endometrial cancer or venous thrombosis and only a modest increase in hot flushes. The benefit persisted in longer follow-up. Low-dose tamoxifen is now offered as an alternative for women who cannot tolerate the standard dose.","status":"positive","asOf":"2026-09-17","links":[{"label":"ClinicalTrials.gov NCT01357772","url":"https://clinicaltrials.gov/study/NCT01357772"}],"tags":["subtype-trials"],"related":[],"cancers":["ductal-carcinoma-in-situ","breast-cancer"],"sections":[],"technologies":[],"targets":[],"drugs":["tamoxifen"],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":["andrea-decensi"],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"nct":"NCT01357772","phase":"3","setting":"Breast intraepithelial neoplasia (atypical ductal hyperplasia, lobular carcinoma in situ or hormone-sensitive ductal carcinoma in situ) after surgery: low-dose tamoxifen 5 mg daily for three years against placebo","sponsor":"Andrea DeCensi, Galliera Hospital, Genoa","result":"Tamoxifen 5 mg daily for three years roughly halved breast cancer events compared with placebo with few serious adverse effects.","yearReported":2019,"enrolled":500,"outcomes":[]},"route":"/trials/tam-01/","neighbours":{"cancer":[{"id":"breast-cancer","kind":"cancer","name":"Breast cancer (all types)","route":"/cancers/breast-cancer/"},{"id":"ductal-carcinoma-in-situ","kind":"cancer","name":"Ductal carcinoma in situ (DCIS)","route":"/cancers/ductal-carcinoma-in-situ/"}],"drug":[{"id":"tamoxifen","kind":"drug","name":"Tamoxifen","route":"/drugs/tamoxifen/"}],"person":[{"id":"andrea-decensi","kind":"person","name":"Andrea DeCensi","route":"/people/andrea-decensi/"}]}}