title: Uncommon breast tumors in perspective: incidence, treatment and survival in the Netherlands.
abstract: The relatively small group of patients with breast tumors other than the ductal, lobular or mixed ducto-lobular types, has reached nonnegligible numbers due to the ongoing increase in the incidence of breast cancer. We investigated stage and grade distribution of uncommon breast tumors using the nation-wide Netherlands Cancer Registry (population 16.5 million) and incidence patterns, treatment and long-term survival (up to 19 years) using the regional Eindhoven Cancer Registry (population 2.4 million). Incidence of all uncommon breast tumors together was 9.2/100,000 person years (age-standardized, ESR). The proportion of stage I tumors was 70% among patients with tubular (n = 3,456) and 40-50% for mucinous (n = 3,482), papillary (n = 1,078), cribriform (n = 503) and neuroendocrine (n = 76) tumors, contrasting to 27, 28 and 36%, respectively among patients with Signet ring cell cancer (n = 75), Paget's disease (n = 818) and the common invasive ductal carcinomas (n = 121,656). A better age-, stage-, and grade-adjusted prognosis was observed for patients with lobular (death risk ratio 0.8, 95%CI: 0.7-0.9), mucinous (0.5, 0.3-0.9), medullary (0.5, 0.3-0.9) and tubular (0.4, 0.2-0.6) carcinoma or phyllodes tumor (0.02, 0.0-0.2), compared with invasive ductal carcinomas. For patients with papillary (0.6, 0.2-1.6) and cribriform (0.1, 0.0-5.1) tumors better prognosis was not statistically significant. In conclusion, histologic type was an essential determinant of survival for about 10% of all newly diagnosed women with invasive breast cancer. Because patients with mucinous, tubular, medullary and phyllodes tumors have such a good prognosis, less aggressive treatment should be considered in some cases whereby specific guidelines are becoming increasingly desirable. Communication to patients with these specific histological types should reflect this.
authors.affiliation: Eindhoven Cancer Registry, Comprehensive Cancer Centre South IKZ, Eindhoven, The Netherlands. research@ikz.nl
authors.forename: Marieke W J
authors.initials: MW
authors.lastname: Louwman
authors.forename: Martine
authors.initials: M
authors.lastname: Vriezen
authors.forename: Mike W P M
authors.initials: MW
authors.lastname: van Beek
authors.forename: M Cathelijne B J E Tutein
authors.initials: MC
authors.lastname: Nolthenius-Puylaert
authors.forename: Maurice J C
authors.initials: MJ
authors.lastname: van der Sangen
authors.forename: Rudi M
authors.initials: RM
authors.lastname: Roumen
authors.forename: Lambertus A L M
authors.initials: LA
authors.lastname: Kiemeney
authors.forename: Jan Willem W
authors.initials: JW
authors.lastname: Coebergh
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000145:classification / Q000453:epidemiology* / Q000473:pathology / Q000628:therapy*; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D015996:Survival Rate; D013997:Time Factors