Brachytherapy-based radiotherapy is associated with improved survival for newly diagnosed metastatic cervical cancer

Long term clinical outcomes of cervical cancer patients who were recommended surgery but did not undergo it: A SEER database study

BACKGROUND

This study analyzed the long-term clinical outcomes of cervical cancer patients recommended surgery but who did not undergo it using the Surveillance, Epidemiology, and End Results (SEER) database. The aim was to identify the subgroups with comparable overall survival (OS) and cancer-specific survival (CSS) through stratified analysis.

METHODS

Cases of cervical cancer were retrieved from SEER database using SEER*Stat software. This included patients in the non-surgery group (recommended surgery but did not undergo it), and a reference surgery group. Propensity score matching balanced differences between the non-surgery and surgery groups. Stratified analysis and log-rank tests were used to identify subgroups within the non-surgery group with comparable OS and CSS to the surgery group.

RESULTS

A total of 30,807 cervical cancer patients were included in the OS and CSS analysis. In the matched cohort (n = 1278), patients in the non-surgery group had significantly lower 5-year CSS (63.2 % vs. 80.1 %, P < 0.001) and 5-year OS (59.0 % vs. 78.0 %, P < 0.001). However, within the matched cohort, there was no statistically significant difference in OS and CSS between the non-surgery and surgery groups in subgroups diagnosed during 2010-2014 (P = 0.064, P = 0.182), 2015-2020 (P = 0.122, P = 0.518), T2 stage (P = 0.139, P = 0.052), T3 stage (P = 0.502, P = 0.317), or with distant metastasis (M1) (P = 0.411, P = 0.520).

CONCLUSION

Patients in the non-surgery group generally exhibited lower long-term clinical outcomes compared to those in the surgery group. However, with advancements in non-surgical treatment techniques, particularly notable in patients with T2, T3, and M1 stages, these differences are gradually diminishing.

Long-term survival in patients with para-aortic metastatic cervical cancer receiving simultaneous integrated boost chemoradiation to positive lymph nodes: a single-center experience

OBJECTIVES

To examine the benefits of extended-field chemoradiation with simultaneous integrated boost to positive lymph nodes, followed by image-guided adaptive brachytherapy in patients with cervical cancer with para-aortic metastasis.

METHODS

This retrospective cohort study enrolled 143 patients diagnosed between January 2011 and July 2023 at a single center. Survival and recurrence were evaluated using the Kaplan-Meier method and log-rank test. Cox regression was employed to identify prognostic factors and adjust for confounding factors. Patients were then stratified according to neoadjuvant chemotherapy, and its impact on survival outcomes was evaluated.

RESULTS

A total of 129 patients completed the entire treatment course. The 5-year overall survival rate was 57.6%, and the para-aortic failure rate was 6.8% after a median follow-up of 61 months (95% CI 49 to 82 months). Multivariate analysis indicated that neoadjuvant chemotherapy, larger primary tumor or pelvic/para-aortic lymph nodes, and lower hemoglobin nadir (for widespread metastasis-free survival only) predicted poorer survival. After propensity score matching, the 5-year para-aortic recurrence-free, widespread metastasis-free, and overall survival rates were 92.2% vs 92.8% (p=0.85), 50.8% vs 72.1% (p=0.007), and 47.5% vs 65.5% (p=0.037), respectively, in groups receiving neoadjuvant chemotherapy or not. Sixteen patients (12.4%) experienced grade 3-4 late toxicities. Patients who received neoadjuvant chemotherapy had a significantly higher incidence of grade 3-4 anemia and neutropenia than those who did not (45.2% vs 26.7% and 38.1% vs 21.8%, respectively), if including another 14 patients who discontinued treatment due to acute vomiting.

CONCLUSION

Chemoradiation with simultaneous integrated boost to positive lymph nodes demonstrates favorable outcomes and acceptable late toxicities in para-aortic metastatic cervical cancer. Neoadjuvant chemotherapy has been shown to adversely affect outcomes, and acute vomiting is a major cause of treatment abortion.

Locoregional Treatment in Patients With Metastatic Cervical Cancer: Benefit of Dose Escalation Strategies

PURPOSE

The objective of this work was to examine the benefit of an intensive locoregional treatment including an image guided adaptive brachytherapy (IGABT) among patients with cervical cancer and extrapelvic extension.

METHODS AND MATERIALS

Medical records of consecutive patients with a metastatic cervical cancer and receiving external beam radiation therapy and IGABT boost in Gustave Roussy Institute as part of their first line of treatment were examined. Depending on tumor sites, patients received pelvic ± para-aortic external beam radiation therapy. For those with visceral or supradiaphragmatic lymph node metastases, chemoradiation was delivered after usually 3 cycles of chemotherapy. All patients received a brachytherapy boost, guided by magnetic resonance imaging and aimed at increasing the dose to the high-risk clinical target volume (CTVHR). Local control (LC), patient overall survival (OS), progression-free survival, and radiation therapy-related side effects were examined, and prognostic factors were searched.

RESULTS

One hundred sixty-four patients were included; 76.2% had para-aortic lymph node extension without distant metastasis (N2) and 23.8% had distant metastatic sites (M1). There was not a statistically significant difference in survival between both groups. With a median follow-up of 36 months, OS, progression-free survival, and LC at 3 years were 55.5% (95% CI, 48%-64%), 40.6% (95% CI, 38%-54%), and 90% (95% CI, 85%-96%), respectively. In multivariate analysis, a D90CTVHR dose ≥80 Gy was significant for better OS (hazard ratio, 0.96; 95% CI, 0.94-0.98; P < .001). Most toxicities were mild to moderate, with 2% grade 3 late urinary toxicity, 7% late grade 2 vaginal sequelae, and 1 grade 3 proctitis. During follow-up, rectovaginal fistula occurred in 2 patients without local relapse.

CONCLUSIONS

IGABT permits dose escalation and high LC rates for patients with cervical cancer and extrapelvic extension. Dose/effect relationships for survival were shown. Because of high frequency of distant events, systemic intensification should be tested more specifically among these patients.

Outcomes associated with treatment to all sites of disease in patients with stage IVB cancer of the cervix

OBJECTIVE

The use of chemoradiation in patients with stage IVB cancer of the cervix was evaluated to determine if definitive treatment offers benefit.

METHODS

A database of 546 patients with cancer of the cervix treated between January 2005 and May 2021 at a tertiary academic medical center was reviewed retrospectively to identify patients with stage IVB disease. Log rank test, regression analysis, and the Kaplan-Meier method were used to identify and compare variables and estimate progression free survival and overall survival.

RESULTS

Thirty-three patients with stage IVB cervical cancer were identified. Median age was 53 years (range 28-78). Pathology subtypes were squamous cell (n=22, 67%), adenocarcinoma (n=8, 24%), and clear cell (n=3, 9%). Metastases were classified as lymphatic (n=14, 42%) or hematogenous (n=19, 58%). Following treatment to all sites with chemoradiotherapy and selected use of surgery (n=23), six patients (26%, lymphatic n=4, hematogenous n=2) remained disease free for a median duration of 4 years (range 3-17 years). Recurrences in the remaining patients were distant (n=13) or local (n=4). All patients in the chemotherapy group (n=10, 100%) progressed. Kaplan-Meier analysis showed that median progression free survival was longer for patients treated at all disease sites than for patients treated with chemotherapy alone (19 vs 11 months, p=0.01). However, this was not the case for overall survival (49 vs 33 months, p=0.15). Patients with metastases limited to lymph nodes also had longer median progression free survival (22 vs 11 months, p=0.04) but not overall survival (p=0.68).

CONCLUSIONS

Patients with stage IVB cancer of the cervix may benefit from treatment to all sites of disease, if feasible and safe, as demonstrated by improved progression free survival.

Evaluation of dose differences between intracavitary applicators for cervical brachytherapy using knowledge-based models

PURPOSE

Currently, there is a lack of patient-specific tools to guide brachytherapy planning and applicator choice for cervical cancer. The purpose of this study is to evaluate the accuracy of organ-at-risk (OAR) dose predictions using knowledge-based intracavitary models, and the use of these models and clinical data to determine the dosimetric differences of tandem-and-ring (T&R) and tandem-and-ovoids (T&O) applicators.

MATERIALS AND METHODS

Knowledge-based models, which predict organ D_2cc, were trained on 77/75 cases and validated on 32/38 for T&R/T&O applicators. Model performance was quantified using ΔD_2cc=D_2cc,actual-D_{2cc,predicted}, with standard deviation (σ(ΔD_2cc)) representing precision. Model-predicted applicator dose differences were determined by applying T&O models to T&R cases, and vice versa, and compared to clinically-achieved D_2cc differences. Applicator differences were assessed using a Student's t-test (p < 0.05 significant).

RESULTS

Validation T&O/T&R model precision was 0.65/0.55 Gy, 0.55/0.38 Gy, and 0.43/0.60 Gy for bladder, rectum and sigmoid, respectively, and similar to training. When applying T&O/T&R models to T&R/T&O cases, bladder, rectum and sigmoid D_2cc values in EQD2 were on average 5.69/2.62 Gy, 7.31/6.15 Gy and 3.65/0.69 Gy lower for T&R, with similar HRCTV volume and coverage. Clinical data also showed lower T&R OAR doses, with mean EQD2 D_2cc deviations of 0.61 Gy, 7.96 Gy (p < 0.01) and 5.86 Gy (p < 0.01) for bladder, rectum and sigmoid.

CONCLUSIONS

Accurate knowledge-based dose prediction models were developed for two common intracavitary applicators. These models could be beneficial for standardizing and improving the quality of brachytherapy plans. Both models and clinical data suggest that significant OAR sparing can be achieved with T&R over T&O applicators, particularly for the rectum.