Stereotactic body radiotherapy (SBRT) and concomitant systemic therapy in oligoprogressive breast cancer patients.

Breast cancer is a heterogenous disease with a deep tailoring level. Evidence is accumulating on the role of stereotactic body radiotherapy (SBRT) in the management of oligometastatic disease, however this is limited in breast cancer. The aim of the present study is to show the effectiveness of SBRT in delaying the switch to a subsequent systemic treatment in oligoprogressive breast cancer patients. Retrospective analysis from two Institutions. Primary endpoint: time to next systemic treatment (NEST). Secondary endpoints: freedom from local progression (FLP), time to the polymetastatic conversion (tPMC) and overall survival (OS). One-hundred fifty-three (153) metastases in 79 oligoprogressive breast cancer patients were treated with SBRT. Median follow-up 24 months. Median NEST 8 months. Predictive factor of NEST at the multivariate analysis (MVA) was the number of treated oligometastases (HR 1.765, 95%CI 1.322-2.355; p = < 0.01). Systemic treatment after SBRT was changed in 29 patients for polymetastatic progression and in 10 patients for oligometastatic progression < 6 months after SBRT. The 2-year FLP in the overall population was 86.7%. A biological effective dose (BED) > 70Gy10 was associated with improved FLP (90% versus 74.2%). The median tPMC was 10 months. At the MVA the only factors significantly associated with tPMC were the number of oligometastases (HR 1.172, 95%CI 1.000-1.368; p = 0.03), and the local control of the treated metastases (HR 2.726, CI95% 1.108-6.706; p = 0.02). SBRT can delay the switch to a subsequent systemic treatment, however patient selection is necessary. Several predictive factors for treatment tailoring have been identified.

Breast cancer bone metastases: an epidemiologic study in selected radiation departments.

AIMS: To quantify radiation treatments for bone metastases from breast cancer in three Sicilian provinces (Messina, Catania, Ragusa) with respect to the general population and the incidence and prevalence of breast cancer in this macro-area in a 8-year period. METHODS: All bone metastasis patients treated using radiotherapy in 8 radiation departments operating in the provinces of Messina, Catania and Ragusa were collected. Among these, metastases from breast carcinoma were analyzed according to year of irradiation. An analysis of breast cancer incidence and prevalence with respect to inhabitants in this macro-area was conducted using literature and census data. RESULTS: From January 2004 to December 2011, irradiation was delivered in 4419 bone metastasis patients. Among these, 1617 had a primary breast cancer with a median treatment per year of 206.5 (range, 164-251); 211 patients were treated in 2004 and 206 in 2011. In 2004, there were 1,048,957 female residents in the three provinces and 1,065,422 in 2011. The reported breast cancer incidence and prevalence in Sicily was respectively 100.79/100,000 and 908.54/100,000 in 2004 and 108.41/100,000 and 1091.29/100,000 in 2010. CONCLUSIONS: There has been an increase in both incidence and prevalence of breast cancer in Sicily. Nevertheless, it seems that there was no increment in skeletal-related events requiring irradiation in such patients in eastern Sicily radiation departments.