MedWire News: A 2-day course of three-dimensional (3D) radiotherapy (RT) delivered in twice-daily fractions up to 18 Gy resulted in no dose-limiting toxicities, and high rates of symptom relief in patient with pelvic cancer, especially those with bleeding, report researchers.
The findings emerge from a phase I study of 3D-RT that aimed to reduce the treated volume and dose administered to surrounding organs in 27 patients with advanced pelvic malignancies. Patients underwent incremental doses from 14 Gy through 18 Gy, and no late toxicities emerged after an average 6 months follow up.
Indeed, the overall response for pain in the cohort was 92%, report Gabriella Macchia (Università Cattolica del S Cuore, Campobasso, Italy) and colleagues in the International Journal of Radiation Oncology Biology Physics.
"Radiotherapy in the palliative setting should provide durable symptomatic relief and optimize logistic issues," write Macchia et al. "Therefore, it is important to find a balance between the treatment duration and intensity to reduce the potential acute and long-term complications."
The team believes that previous studies of short-course RT in this patient population have reported a high incidence of severe side effects because treatment volumes included the whole pelvis and delivery was via a 2D-RT technique.
Patients in the current study, aged an average 72 years and with mainly gynecologic (48%) and colorectal (34%) cancers, underwent each dosing regimen of the computed tomography treatment without experiencing dose-limiting toxicities. The most common RT toxicity was grade 1 genitourinary (30%), measured on the Radiation Therapy Oncology Group scale, and no patients reported grade 3 acute toxicities.
Bleeding (48%) and pain (33%) were the most frequent symptoms observed at baseline, and 89% of patients had complete or partial remission of these after treatment. Indeed, 50% of those with baseline bleeding had total symptom resolution, note the authors.
Of the 12 patients who received RT for pain control, five (42%) had complete pain relief posttreatment, and six (50%) had a greater than 30% reduction of pain measured using a visual analog score.
In addition to the low toxicity rate and high rate of symptom control, "the rapid treatment of patients with clinically relevant bleeding could potentially effect a reduced hospitalization time, with a likely optimization of cost effectiveness," conclude Macchia and co-workers.
MedWire (www.medwire-news.md) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2012