PROGNOSTIC COMPARISON OF 3 CLASSIFICATIONS FOR MEDULLARY CARCINOMAS OF THE BREAST

The aim of this study was to make prognostic comparisons between the m odified scheme of Pedersen et al. the definitions of Tavassoli and the Ridolfi criteria for medullary carcinomas, Sixty breast carcinomas pr imarly diagnosed as medullary carcinomas were reclassified into typica l medullary carcinoma (TMC), atypical medullary carcinoma (AMC) and no n-medullary carcinoma (NMC) according to the three classifications. Th e Ridolfi classification proved to be superior to the two other scheme s in discriminating survival differences between the three groups TMC, AMC and NMC. All 13 patients with TMC are still alive indicating an e xcellent prognosis, while 29% and 39% of the 47 patients in the AMC an d NMC category, respectively, have died of their disease, In the simpl ified system of Pedersen et al, the survival at 10 years for TMC patie nts decreased to 75% and no significant survival difference between th e three groups could be demonstrated, As the prognosis for AMC proved to be worse compared to TMC and in fact was similar to NMC with values of 43% at 10 years in the Ridolfi classification, we find no reasons to maintain this category. We conclude that as long as no alternative and more easily applicable diagnostic method exists, pathologists shou ld still apply the Ridolfi criteria on these tumours with medullary fe atures leaving two diagnostic possibilities: TMC or NMC (i.e. poorly d ifferentiated ductal carcinoma). Only lesions that fulfil all six crit eria without any doubt should be diagnosed as TMC, thus avoiding overd iagnosis and a resulting risk of undertreatment.