Brachytherapy boost in the neoadjuvant radiation therapy for locally advanced rectal cancer at King Abdulaziz University Hospital

Abstract EN

The aim is to evaluate the pathological complete response and toxicity when using brachytherapy boost as part of the preoperative chemoradiation therapy in patients with rectal cancer.

A retrospective review of all patients with rectal cancer treated at King Abdulaziz University Hospital.

Fifty-five patients had neoadjuvat radiotherapy 45 Gy in 25 fractions of external beam radiation as Phase I of radiotherapy followed by external beam boost : 540 cGy / 3 fractions in 31 patients or Ir192 HDR brachytherapy boost in 17 patients.

The pathological response rate, toxicity profile, overall survival and disease free survival was compared between different radiation therapies modalities.

The pathological response rate was complete in 14 25.5 % patients, partial (PR) in 29 (52.7 %) patients, unknown (did not do surgery) in 9 (16.5 %) patients and stable disease in 3 (5.4 %) patients.

In brachytherapy boost, pathological complete response was 47 % vs.

18 % external beam boost (p = 0.004).

Toxicity profile was better in the brachytherapy group.

Overall survival was 93 % and the disease free survival was 60 % which were not influenced by the modality of radiation therapy used.

High Dose Rate Brachytherapy boost result in a higher pathological response rate without increase in side effect as compared to the external beam radiation boost in the neoadjuvant radiation therapy for locally advanced rectal cancer