Cervical cancer: less side effects with specialized radiation therapy

Cervical cancer: less side effects with specialized radiation therapy

19 Oct 2015

For cervical cancer patients undergoing post-surgical radiation therapy, image-guided intensity-modulated radiation therapy (IG-IMRT) resulted in a 14% reduction in moderate-to-severe bowel side effects when compared to conventional three- dimensional conformal radiation therapy (3-D CRT). This is reported by a phase 3 clinical study.

Post-operative pelvic radiation therapy is the current standard of care for many patients with cervical cancer, yet may affect surrounding organs and tissue and be associated with long-term gastrointestinal side effects. On the other hand, IG-IMRT uses technology to manipulate beams of radiation to conform to the shape of a tumor, thus allowing clinicians to limit exposure to surrounding tissue.

The patients participating in the study had no pre-existing bowel disease

The phase 3 randomized clinical trial, conducted at Advanced Centre for Treatment Research and Education in Cancer (ACTREC), Tata Memorial Centre in Mumbai, India, included 240 patients, ages 18 and over who were undergoing adjuvant chemo-radiation therapy (combined chemotherapy and radiation therapy) and had no pre-existing bowel disease or injury.

This planned interim analysis of the study assessed 117 of the patients who had completed an average of 20-months follow-up. Patients were categorized:

• Into two groups: 56 patients received 3-D CRT and 61 patients received IG-IMRT.
• Patient groups were randomized and had similar treatment histories, with 41.3% (23 patients) of the 3-D CRT group having radical hysterectomies and 43.5% (27 patients) of the IG-IMRT group having radical hysterectomies.
• Additionally, 91.8% (51 patients) of the 3-D CRT group had chemo-radiation therapy, with 85.5% (52 patients) of the IG-IMRT group undergoing chemo-radiation therapy.

"Encouraging initial results”

The analysis of the results revealed that:

• In the 3-D CRT group, 58.9% (33 patients) experienced ≥2 acute bowel toxicity (indicating moderate to severe diarrhea, vomiting, nausea, lower abdominal distension or pain) compared to 54% (33 patients) in the IG-IMRT group.
• The reported late grade ≥2 bowel toxicity was 25% (14 patients) in the 3-D CRT group and 11.4% (7 patients) in the IG-IMRT group.
• the late grade ≥3 bowel toxicity (indicating severe diarrhea, lower abdominal pain, subacute intestinal obstruction requiring medical or surgical intervention, bowel perforation or death) was 17.6% (10 patients) in the 3-D CRT group and 3.2% (2 patients) in the IG-IMRT group (p=0.02).
• Further, research indicated that neither the surgery type nor the administration of CRT had an impact on bowel side effects.

“These initial results of this interim analysis are encouraging and trend toward possibly a clinically important reduction in moderate-to-severe bowel side effects with the use of IG-IMRT, however at interim analysis the results are statistically nonsignificant,” said Supriya Chopra, MD, lead study author and associate professor of radiation oncology at ACTREC, Tata Memorial Centre in Mumbai, India.

“While we evaluated patients with cervical cancer in this trial, a significant proportion of patients with other cancers undergo postoperative pelvic radiation worldwide. Therefore, the results of this trial could impact the choice of future radiation delivery technique for various pelvic malignancies.”

 

Source: eCancer News