Medical Radiology and Radiation Safety. 2013. Vol. 58. No. 5. P. 51-53

RADIATION THERAPY

A.P. Dmitrenko, N.A. Tolmacheva

Influence of Time Intervals between Radiotherapy and Surgical Treatment on Survival Rate of the Breast Cancer Patients

Oncodispensary, Rostov-on-Don, Russia, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Abstract

Purpose: To estimate influence of time intervals on the overall (OS) and recrudescence free (RFS) survival rate of breast cancer patients (BCP). Two time intervals were considered 1) between neoadjuvant radiation therapy and operation (an interval NRT→operation); 2) between operation and adjuvant radiation therapy (an interval operation→ART).

Material and methods: Sample of patients BC (T_1–4N0_–3M₀), observed in 1990–2004 (n = 2132). All patients executes radical mastectomy. Only NRT it is spent 239 (11.2 %) by the patient, only ART – 1155 (54.2 %) the patient, NRT in a combination with ART it is spent 738 (34.6 %) by the patient. The estimation of influence of time intervals on survival rate of BCP was carried out taking into account three factors: 1) a variant of carrying out radial therapy (only NRT, only ART, NRT in a combination with ART); 2) prevalence of tumor process (T_1–2N–, T_3–4N–, T_1–2N+, T_3–4N+); 3) age of patients (49 years and less, 50–59 years, 60 years also are more senior). Influence of time intervals has been investigated separately in groups of patients rightsided and left-sided BC (Statistica 8).

Results: Under a combination NRT and ART authentically negative influence of time intervals on survival rate of patients BC is revealed: 1) an interval operation→ART at patients of an age category of 50–59 years at T_1–2N– (OS: p = 0.005; BCP: p = 0.018); 2) an interval in patients with right-sided cancer of an age category of 50–59 years (OS: p = 0.017; DFS: p = 0.08); 3) an interval lNRT→operation in patients with left-sided cancer of an age category of 60 years also is more senior (OS: p = 0.001; BCP: p = 0.013); 4) an interval operation→ART a left-sided cancer of an age category of 50–59 years (OS: p = 0.01; DFS: p = 0.004).

Conclusion: Under certain conditions the increase in time intervals NRT→operation and operation→ART authentically reduces survival rate of patients BC. At combination NRT and ART a laterality of a tumor lesion defines influence of time intervals on survival rate of patients BC of an age category of 50–59 years.

Key words: radial therapy, breast cancer, laterality, time interval