Trends in lobular carcinoma in situ management: endocrine therapy use in California and New Jersey

Purpose: The diagnosis of lobular carcinoma in situ (LCIS) is a strong risk factor for breast cancer. Endocrine therapy (ET) for LCIS has been shown to decrease breast cancer risk substantially. The purpose of this study was to evaluate the trends of ET use for LCIS in two large geographic locations. Patients and methods: We identified women, ages 18 through 75, with a microscopic diagnosis of LCIS in California (CA) and New Jersey (NJ) from 2004 to 2014. We evaluated trends in unadjusted ET rates during the study period and used logistic regression to evaluate the relationship between patient, tumor, and treatment characteristics, and ET use. Results: We identified 3,129 patients in CA and 2,965 patients in NJ. The overall use of ET during the study period was 14%. For the combined sample, women in NJ were significantly less likely to utilize ET then their counterparts in CA (OR 0.77, CI 0.66–0.90, NJ vs. CA). In addition, patients in the later year period (OR 1.27, CI 1.01–1.59, 2012–2014 vs. 2004–2005) and women who received an excisional biopsy (OR 2.35, CI 1.74–3.17), were more likely to utilize ET. Uninsured women were less likely to receive ET (OR 0.61, CI 0.44–0.84, non-insured vs. insured status). Conclusions: We observed that an increasing proportion of women are using ET for LCIS management, but geographical differences exist. Health insurance status played an important role in the underutilization of ET. Further research is needed to assess patient outcomes given the variations in management of LCIS.