Para-Aortic Nodal Radiation in the Definitive Management of Node-Positive Cervical Cancer

Abstract

ObjectivesTo investigate the safety and outcomes of elective para-aortic (PA) nodal irradiation utilizing modern treatment techniques for patients with node positive cervical cancer.MethodsPatients with pelvic lymph node positive cervical cancer who received radiation were included. All patients received radiation therapy (RT) to either a traditional pelvic field or an extended field to electively cover the PA nodes. Factors associated with survival were identified using a Cox proportional hazards model, and toxicities between groups were compared with a chi-square test.Results96 patients were identified with a mean follow up of 40 months. The incidence of acute grade ≥ 2 toxicity was 31% in the elective PA nodal RT group and 15% in the pelvic field group (Chi-square p = 0.067. There was no significant difference in rates of grade ≥ 3 acute or late toxicities between the two groups (p>0.05). The KM estimated 5-year OS was not statistically different for those receiving elective PA nodal irradiation compared to a pelvic only field, 54% vs. 73% respectively (log-rank p = 0.11).ConclusionsElective PA nodal RT can safely be delivered utilizing modern planning techniques without a significant increase in severe (grade ≥ 3) acute or late toxicities, at the cost of a possible small increase in non-severe (grade 2) acute toxicities. In this series there was no survival benefit observed with the receipt of elective PA nodal RT, however, this benefit may have been obscured by the higher risk features of this population. While prospective randomized trials utilizing a risk adapted approach to elective PA nodal coverage are the only way to fully evaluate the benefit of elective PA nodal coverage, these trials are unlikely to be performed and instead we must rely on interpretation of results of risk adapted approaches like those used in ongoing clinical trials and retrospective data.

Treatment Strategies and Prognostic Factors of 2018 FIGO Stage IIIC Cervical Cancer: A Review

“… 85 In cervical cancer, the incidence of common iliac LNM is lower, but once common iliac LNM occurs, the OS is significantly reduced. 46 , 47 , 80 , 83 , 86 , 87 In a prospective cohort study of 560 patients at a single center, the risk of recurrent disease was shown to increase incrementally on the basis of the most distant level of LN involvement at PET, with a hazard ratio of 2.40 (95% confidence interval: 1.63, 3.52) for pelvic involvement, 5.88 (95% confidence interval: 3.80, 9.09) for para-aortic involvement, and 30.27 (95% confidence interval: 16.56, 55.34) for supraclavicular involvement. 12 …”

The role of proton therapy in gynecological radiation oncology

“…Treatment of these nodal regions is challenging given significant amounts of bowel, kidney, spine, and other exposed organs. Modern treatment planning including intensity-modulated radiation has allowed for more comfortable treatment of these regions generally up to the level of renal vessels, and even dose escalation around the duodenum for gross nodal disease 40. Our clinic has demonstrated the feasibility of using proton therapy for extended-field therapy in post-operative cancers15 (Figure 3).…”

“…Modern treatment planning including intensity-modulated radiation has allowed for more comfortable treatment of these regions generally up to the level of renal vessels, and even dose escalation around the duodenum for gross nodal disease. 40 Our clinic has demonstrated the feasibility of using proton therapy for extended-field therapy in post-operative cancers 15 (Figure 3). Treatment of the para-aortic nodes with radiation is often employed in patients with early-stage testicular seminoma, and is feasible with proton therapy.…”

A modified delineation method of para‐aortic nodal clinical target volume in patients with locally advanced cervical cancer

“… 8 , 9 On the contrast, some studies indicated that prophylactic EFI did not reduce the risk of para‐aortic nodal recurrence and confer survival benefits in patients with positive pelvic lymph node cervical cancer. 10 , 11 Anyway, prophylactic EFI is considered to be safe in modern radiotherapy techniques without a significant increase in severe toxicities in patients with cervical cancer. 11 , 12 , 13 …”

“… 10 , 11 Anyway, prophylactic EFI is considered to be safe in modern radiotherapy techniques without a significant increase in severe toxicities in patients with cervical cancer. 11 , 12 , 13 …”