The evidence supporting this protocol is provided by a phase III multicentre randomized trial (GOG-92)r involving 277 women with stage 1B squamous, adenosquamous carcinoma or adenocarcinoma of the cervix. Between March 1988 and September 1995, 116 patients were randomized to adjuvant pelvic radiotherapy and 101 patients underwent observation only following radical hysterectomy and pelvic lymphadenectomy. Radiotherapy was started within 4 to 6 weeks post-operatively, and consisted of external beam irradiation only. The pelvis was treated to a dose of 46 Gy in 23 fractions to 50.4 Gy in 28 fractions over 4.5 to 6 weeks. The primary end point was recurrence-free interval and secondary end points were overall, progression-free survival and toxicity.
- After a median follow up of 10 years, 15.3% (RT) vs 27.9% (no treatment) of patients developed both local and distant cancer recurrences.
- Adjuvant pelvic radiotherapy following radical surgery significantly reduced the risk of recurrence by 47% (relative risk = 0.53, P = 0.008).
- When adjusted for all combinations of risk factors including tumour size, LVI and depth of invasion, the risk of recurrence was significantly reduced by 44% in the radiation group (p=0.019), with a recurrence free rate of 88% (RT) vs 79% (NFT) at 2 years.r
- A 10 year follow up of the GOG92 RCT by Rotman et alr confirmed the 46% reduction in risk of recurrence (hazard ratio HR=0.54, p=0.007) in women with Stage IB cancer and reported a statistically significant reduction in risk of progression or death (HR=0.58,p=0.009).
- On comparison, higher failure rates were experienced by patients with adenocarcinoma and adenosquamous histologies who did not receive radiotherapy, 44% (11/25) NFT vs 8.8% (3/34) RT.
© Rotman et al, 2006r
© Rotman et al, 2006r
A Cochrane Review meta-analysisr of two RCTs (n=397 women) included data from GOG-92 and another Phase II study. It compared adjuvant treatment (RT) versus no further treatment (NFT), and reported no significant difference in survival at 5 years between the NFT and RT groups (RR=0.8, 95% CI:0.3-2.4). However, women who received radiation had a significantly lower risk of disease progression at five years (RR = 0.6, 95% CI:0.4-0.9).