BackgroundInclusion of patient-reported outcomes (PROs) in oncology clinical trials is strongly recommended. However, selecting the most appropriate patient-reported outcome measures (PROMs) is not easy. This study aimed to develop a breast cancer (BC) specific comprehensive archive of PROMs. MethodsAs part of the PRO4All project, we identified available PROMs in oncology by searching facit.org, eortc.org, eprovide.mapi-trust.org, PubMed, ema.europa.eu (European Public Assessment Reports) and published reviews. For this analysis, only BC tools were extracted. We described information about PROM name, type of questionnaire, questionnaire variant(s), recall period, number of items, and presence of minimum clinically important difference (MCID) reference in literature. Then, we assigned each item to a specific domain according to a predefined taxonomy of 38 items for outcome classification. ResultsWe identified and analyzed 383 PROMs. Of these, 29 were BC specific, but 2 were excluded because the questionnaires description was not available. 6 (22.2 %) were variants of another questionnaire. All questionnaires were self-reported. In 6 cases (22.2 %) the recall period to consider was the “last week”. The mean number of items per questionnaire was 25.81 (range 6–71). 602 items were assigned to an outcome domain: emotional functioning/wellbeing in 26.6 % of cases, physical functioning in 14.1 %, delivery of care in 10.8 %, and general outcomes in 10.5 %. MCID reference was found only in 4 (14.8 %) cases. ConclusionsThe newly developed archive represents a useful tool to optimize the use of PROMs in the evaluation of treatments in BC patients, promoting a patient-centered approach both in clinical research and practice.