Clinical and technical feasibility of ultra-boost irradiation in dominant intraprostatic lesion by Tomotherapy: Preliminary experience and revision of literature - Abstract

AIM: The aim of this paper is to present our experience of dominant intra-prostatic lesions (DIL) irradiation up to an EQD2 of 93,2 Gy with Helical Tomotherapy.

METHODS: Between March 2012 and December 2014, 15 staged II-III patients with intermediate-high risk prostate cancer were enrolled in our protocol of DIL dose escalation by Tomotherapy. All patients were submitted to a multiparametric MRI (including DCE and DWI series), in order to visualize DILs. Considering a mean α/β ratio of 3 for prostate cancer the prescribed doses were: 83.2 Gy in 32 fractions of 2.6 per fraction (EQD2 = 93.2 Gy) on the DILs, 75.2 Gy in 32 fractions of 2.35 Gy per fraction (EQD2 = 80.5 Gy) on the prostate gland and 67.2 Gy in 32 fraction of 2.1 (EQD2 = 68.5 Gy) on the seminal vesicles.

RESULTS: With a mean follow up of 16 months (range 2-39), no overall severe acute toxicities > G3 were observed; one patient out of 15 (6.6%) had acute gastrointestinal (GI) toxicity equal to G2, while two cases (13.3%) had G2 acute genitourinary (GU) toxicity. No > G2 Late toxicity was observed. At last follow up, for all patients, the Biochemical disease Free Survival was 100%.

CONCLUSION: The irradiation of the whole prostate and seminal vesicles up to an EQD2 of 80.5 Gy and of DILs up to 93.2 Gy was clinically feasible and safe, without acute severe toxicity. Although with a short follow-up, late toxicities are currently absent and no patient relapsed.

Written by:
Garibaldi E, Delmastro E, Gabriele D, Bresciani S, Russo F, Di Dia A, Cattari G, Belli G, Gabriele P.   Are you the author?
Radiotherapy, Divisions of FPO-IRCCS Cancer Center, Candiolo, Torino, Italy.  

Reference: Panminerva Med. 2015 Apr 29. Epub ahead of print.

PubMed Abstract
PMID: 25923839 Prostate Cancer Section