Clinical Investigations Effectiveness of two different HDR brachytherapy regimens with the same BED value in cervical cancer

Abstract

PurposeTo analyze the effectiveness of biologically effective dose (BED) in two different regimens of HDR brachytherapy keeping the same total BED to point A and to compare the relationship of overall treatment time in terms of local control and bladder and rectal complications.Material and methodsThe study included two groups comprising a total of 90 cervical cancer patients who underwent external beam radiotherapy (EBRT) followed by HDR intracavitary brachytherapy (ICBT). EBRT treatment was delivered by a Co-60 teletherapy unit to a prescribed dose of 45 Gy with 1.8 Gy per fraction in 25 fractions over a period of five weeks. Parallel opposed anterior–posterior (AP/PA) fields with no central shielding were used, followed by the HDR ICBT dose, to point A, of either two fractions of 9.5 Gy with a gap of 10 days, or three fractions of 7.5 Gy with a gap of 7 days between the fractions. Gemcitabine (dose of 150 mg/m2) was given weekly to all the patients as a radiosensitizer. The calculate BED3 to point A was almost the same in both groups to keep the same late complication rates. The doses, and BED10 and BED3, were calculated at different bladder and rectal point as well as at the lymphatic trapezoid points. During and after treatment patients were evaluated for local control and complications for 24 months.Results and ConclusionsDoses and BEDs at different bladder, rectal and lymphatic trapezoid points, local control, and complications in both HDR ICBT groups did not have statistically significant differences (p > 0.05). Both HDR ICBT schedules are well tolerable and equally effective.

Comparison of two high dose rate intracavitary brachytherapy regimens in treatment of cervical cancer: a preliminary report

“…Novetsky et al reported a 5-year PFS of 75% in a trial of 77 patients treated with EBRT and ICR with 9 Gy per fraction for 2 fractions [ 13 ]. Passi et al, reported a 6-month local recurrence of 3.2% in patients who received ICR with 9.5 Gy × 2 fractions compared to 5.4% in patients who received 7.5 Gy per fraction [ 14 ]. In a trial of 604 patients, Hendry et al found that patients who got 9 Gy × 2 fractions had a 5-year local control rate of 82 percent and patients who received 7 Gy × 4 fractions had a 5-year local control rate of 89 percent (p = 0.72) [ 15 ].…”

“…The institutional protocol utilized a dose fraction of 7.5 Gy, while a dose fraction of 9 Gy was selected based on the findings of multiple studies available in the literature which a demonstrated comparable to superior local control with higher doses per fractionation, despite a reduction in the overall dose of brachytherapy administered [8,[10][11][12][13][14][15][16].…”

Comparative Study between Two Fractions of 9Gy & Three Fractions of 7Gy High Dose Rate Brachytherapy Following Concurrent Chemo Radiotherapy in Patients with Locally Advanced Carcinoma of Uterine Cervix

“…At the end of 6 months 90% and 86.7% patients of both treatment group achieved complete response. Passi et al in their study found 80% and 85% complete response using HDR brachytherapy of 9.5 Gy in two fractions and 7.5 Gy in three fractions 11 . No difference in local control, disease free survival and toxicities had been found in the study of Patel et al (2011) where comparison done between 9 Gy per fraction in two fractions & 6.8 Gy per fraction in 3 fractions in 104 patients of stages IIB and IIIB of cervical carcinoma who were treated with EBRT and HDR ICBT 12 .…”

Toxicity outcome of concurrent teletherapy and brachytherapy compared with teletherapy followed by brachytherapy in locally advanced carcinoma cervix

“…The high dose rate intracavitary brachytherapy in a higher number of insertions with smaller doses per insertion is associated with higher radiobiological effects and reduced toxicity. 6 The aim of this study was to compare the toxicity outcome of concurrent teletherapy and brachytherapy with teletherapy followed by brachytherapy using two different fractionation schedules in locally advanced cervical carcinoma (stage IIB-IVA).…”