Recurrencia local con y sin Boost.

Factores pronosticos de recurrencia local con y sin el agregado de Boost en cáncer de mama.

Prognostic Factors for Local Control in Breast Cancer After Longterm Follow-up in the EORTC Boost vs No Boost Trial: A Randomized Clinical Trial.
Vrieling, C.; van Werkhoven, E.; Maingon, P.; Poortmans, P.; Weltens, C.; Fourquet, A.; Schinagl, D.; Oei, B.; Rodenhuis, C.C.; Horiot, J.C.; Struikmans, H.; Van Limbergen, E.; Kirova, Y.; Elkhuizen, P.; Bongartz, R.; Miralbell, R.; Morgan, D.A.; Dubois, J.B.; Remouchamps, V.; Mirimanoff, R.O.; Hart, G.; Collette, S.; Collette, L.; Bartelink, H.; European Organisation for Research and Treatment of Cancer, Radiation Oncology and Breast Cancer, G.r.oups.
Vol. 3 Nr. 1 Página: 42 - 48 Fecha de publicación: 01/01/2017

Resumen:
Importance: Prognostic factors of ipsilateral breast tumor recurrence (IBTR) may change over time following breast-conserving therapy. Objective: The EORTC "boost no boost" trial showed that young age and high-grade invasive carcinoma were the most important risk factors for IBTR. This study reanalyses pathological prognostic factors related to IBTR using long-term follow-up. De-sign, Setting, and Participants: Participants included 5569 early-stage breast cancer patients, treated with breast-conserving surgery (BCS) and whole-breast irradiation (WBI), who were randomized between no boost and a 16-Gy boost in the EORTC phase III "boost no boost" trial (1989-1996). A total of 1616 patients with a microscopically complete resection (according to local pathologists), included in the central pathology review, have been analyzed in this study. Median follow-up was 18.2 years. Interventions: No further treatment or 16-Gy boost, after BCS and 50-Gy WBI. Main Outcomes and Measures: Time to ipsilateral breast tumor recurrence (IBTR) as first event. Results: The 20-year cumulative incidence of IBTR in 1616 patients (160 events observed) was 15% (95% CI, 12%-17%). Young age (P < .001) and presence of ductal carcinoma in situ (DCIS) (HR, 2.15; 95% CI, 1.36-3.38; P = .001) were associated with an increased risk of IBTR in multivariable analysis. The cumulative incidence of IBTR at 20 years was 34% (95% CI, 25%-41%), 14% (95% CI, 10%-18%), and 11% (95% CI, 8%-15%), in patients 40 years or younger, 41 to 50 years and 50 years or older, respectively (P < .001). This incidence was 18% (95% CI, 14%-22%) and 9% (95% CI, 6%-12%) for tumors with and without DCIS (P < .001). High-grade tumors relapsed more frequently early during follow-up but the relative effect of age and presence of DCIS seemed stable over time. The boost reduced the 20-year IBTR incidence from 31% (95% CI, 22%-39%) to 15% (95% CI, 8%-21%) (HR, 0.37; 95% CI, 0.22-0.62; P < .001) in high-risk patients (=50 years with DCIS present). Conclusions and Relevance: The association of high-grade invasive tumor with IBTR diminished during follow-up, while the effect of DCIS adjacent to invasive tumor seemed to remain stable. Therefore, patients with high-grade invasive tumors should be monitored closely, especially in the first 5 years, while additional DCIS is an indication for longer follow-up, emphasizing the importance of long-term trial follow-up to estimate absolute effects accurately. Trial Registration: clinicaltrials.gov Identifier: NCT02295033.

Acceda al artículo completo aquí: https://www.ncbi.nlm.nih.gov/pubmed/27607734