Efficacy
The evidence supporting this protocol is provided by two meta-analyses and several RCTs.rrrrrr
The 2010 Cochrane Review of 13 randomised controlled trials (RCTs) including 3128 women with stage IB to IVA cervical cancer compared chemoradiation therapy to radiation therapy alone. They reported a 6% improvement in 5 year survival with chemoradiation therapy (HR=0.81, 95% CI 0.71 to 0.91 and P<0.001).r Local and distant recurrence/progression and improved disease free survival (DFS) were also improved with chemoradiation therapy. An absolute DFS of 8% (50% to 58%, HR 0.78 (95% CI 0.70 to 0.87), p<0.001) at 5 years was reported, with similar significant benefits noted of chemoradiation therapy on 5 year locoregional DFS (5%, p<0.001). Additionally, at 5 years, there was similar time to locoregional recurrence/progression (6%, p=0.00009) and metastases free survival (7%, p<0.001).
Figure 1. Simple (unstratified) Kaplan Meier Curves for Overall Survival: chemoradiation therapy (CTRT) versus radiation therapy (RT) and chemoradiation therapy plus chemotherapy (CT) versus radiation therapy.
© Cochrane Review 2010r
Figure 2. Subgroup analysis for FIGO stage for chemoradiation therapy versus radiation therapy trials only (overall survival and disease free survival).
© Cochrane Review 2010r
For stage IB and IIA cervical cancer, radiation therapy is equivalent in terms of effectiveness (local control and survival) and has less morbidity when compared to surgery.r Adverse pathological features in the surgical group necessitated adjuvant radiation therapy in 64% of patients and the combination of surgery and radiation therapy resulted in greater toxicity than either therapy alone.
Post-operative radiation therapy should be avoided by appropriate selection of patients for definitive radiation therapy . Patients with FIGO stage IIB cancers or nodal involvement or size >4 cm should be treated with radiation therapy rather than surgery.
In patients with FIGO stage IB2 and greater cancers, concurrent chemotherapy has significant advantages in effectiveness over radiation therapy alone.r Longer follow up from RTOG 9001 has shown an absolute benefit of 26% in 8 year overall survival (41% to 67%) and 25% (36% to 61%) in 8 year disease free survival. Local control is also significantly improved (65% to 82% at 8 years). However, chemoradiation therapy is associated with greater toxicity than radiation therapy alone, particularly acute haematological and gastrointestinal toxicity. Late toxicity is not well documented and treatment related deaths are rare.
The benefit of adjuvant chemotherapy following definitive chemo-irradiation and brachytherapy was investigated in the phase 3 randomised trial (OUTBACK). Results were presented at ASCO 2021 plenary which showed no overall survival benefit with the addition of adjuvant chemotherapy.r