Multi-institutional Observational Study of Prophylactic Extended-Field Concurrent Chemoradiation Therapy Using Weekly Cisplatin for Patients With Pelvic Node-Positive Cervical Cancer in East and Southeast Asia

Prophylactic Extended-Field Irradiation Versus Pelvic Irradiation in Patients With Cervical Cancer With 2018 FIGO Stage IIIC1 Disease

PURPOSE

The aim of this study was to compare the survival rates and toxicities of prophylactic extended-field radiation therapy (EFRT) and pelvic radiation therapy (PRT) among patients with cervical cancer with 2018 International Federation of Gynecology and Obstetrics (FIGO) stage IIIC1 disease.

METHODS AND MATERIALS

We retrospectively analyzed patients with 2018 FIGO stage IIIC1 disease who were treated with definitive concurrent chemoradiotherapy at our institute between 2011 and 2015. A dose of 50.4 Gy in 28 fractions was delivered to the pelvic region (by PRT) or the pelvic plus para-aortic lymph node region (by EFRT) with intensity modulated radiation therapy. The first-line regimen of concurrent chemotherapy was weekly cisplatin.

RESULTS

A total of 280 patients were included, with 161 patients treated with PRT and 119 patients treated with EFRT. After propensity score matching (1:1), 71 pairs of patients were selected. The respective 5-year rates of the patients treated with PRT and EFRT were 61.9% and 85.0% for overall survival (P = .025) and 53.0% and 77.9% for disease-free survival (DFS) (P = .004), respectively, after matching. In the subgroup analysis, patients were grouped into a high-risk group (122 patients) and a low-risk group (158 patients) based on 3 factors: positive common iliac lymph nodes, ≥3 pelvic lymph nodes, and 2014 FIGO stage IIIB disease. In both the high-risk and low-risk groups, EFRT significantly improved DFS compared with PRT. The rates of grade ≥3 chronic toxicities were 1.2% and 5.9% in the PRT and EFRT groups, respectively (P = .067).

CONCLUSIONS

In comparison to PRT, prophylactic EFRT was associated with improved overall survival, DFS, and para-aortic lymph node control in patients with cervical cancer with FIGO stage IIIC1 disease. The incidence of grade ≥3 toxicities was higher in the EFRT group than in the PRT group, although the difference was not significant.

Significance of Hypofractionated Radiotherapy in Postoperative Irradiation for Breast Cancer: An Asian Multi-institutional Prospective Study

AIMS

There is a need for the adequate distribution of healthcare resources in Southeast Asia. Many countries in the region have more patients with advanced breast cancer who are eligible for postmastectomy radiotherapy (PMRT). Therefore, it is critical that hypofractionated PMRT is effective in most of these patients. This study investigated the significance of postoperative hypofractionated radiotherapy in patients with breast cancer, including advanced breast cancer, in these countries.

MATERIALS AND METHODS

Eighteen facilities in 10 Asian countries participated in this prospective, interventional, single-arm study. The study included two independent regimens: hypofractionated whole-breast irradiation (WBI) for patients who had undergone breast-conserving surgery and hypofractionated PMRT for patients who had undergone total mastectomy at a dose of 43.2 Gy in 16 fractions. In the hypofractionated WBI group, patients with high-grade factors received additional 8.1 Gy boost irradiation sessions for the tumour bed in three fractions.

RESULTS

Between February 2013 and October 2019, 227 and 222 patients were enrolled in the hypofractionated WBI and hypofractionated PMRT groups, respectively. The median follow-up periods in the hypofractionated WBI and hypofractionated PMRT groups were 61 and 60 months, respectively. The 5-year locoregional control rates were 98.9% (95% confidence interval 97.4-100.0) and 96.3% (95% confidence interval 93.2-99.4) in the hypofractionated WBI and hypofractionated PMRT groups, respectively. Regarding adverse events, grade 3 acute dermatitis was observed in 2.2% and 4.9% of patients in the hypofractionated WBI and hypofractionated PMRT groups, respectively. However, no other adverse events were observed.

CONCLUSION

Although further follow-up is required, hypofractionated radiotherapy regimens for postoperative patients with breast cancer in East and Southeast Asian countries are effective and safe. In particular, the proven efficacy of hypofractionated PMRT indicates that more patients with advanced breast cancer can receive appropriate care in these countries. Hypofractionated WBI and hypofractionated PMRT are reasonable approaches that can contain cancer care costs in these countries. Long-term observation is required to validate our findings.

Prophylactic extended-field irradiation for locally advanced cervical cancer

Concomitant chemoradiotherapy is the standard treatment for locally advanced cervical cancer. Pelvic irradiation is commonly recommended for patients with negative para-aortic lymph nodes(PALNs). However, owing to the development of imaging-guided brachytherapy, distant failure has become the main failure pattern. The PALNs are a vital site of distant metastasis, and the para-aortic region may contain occult microscopic metastases that are barely detected owing to imaging technology restriction. The prognostic of patients who experienced PALN failure is dismal. Typically, there are four ways to decrease PALN failure. First, surgical staging can be performed to assess the occurrence of metastasis in the para-aortic region; however, the application of surgical staging is decreasing owing to controversial survival benefits and accompanying complications of surgery. Second, regular imaging surveillance and timely salvage of early recurrences could reduce PALN failure. Third, better systemic adjuvant therapy could be recommended since it has enormous potential to reduce distant metastases and improve overall survival. Fourth, performing prophylactic extended-field irradiation (EFI), including pelvic and para-aortic region irradiation, can sterilize occult microscopic metastases in the para-aortic region and improve survival. Prior investigations have revealed that prophylactic EFI could reduce PALN failure as well as distant metastasis and present the benefit of survival. Yet, owing to the serious morbidity induced by enlarged irradiation field in the era of conventional irradiation techniques, further research on EFI is stagnated. Nowadays, with the development of new technologies, intensity modulated radiation therapy can deliver a higher dose to tumors with acceptable toxicity. Prophylactic EFI regained attention. However, the inclusion criteria of prophylactic EFI in existing studies reveal great discrepancies. Thus, it is urgent to precisely identify indications for better survival and lower complications in patients with cervical cancer. In this review, we identify indications and summary guidelines for prophylactic EFI, which may provide a foundation for further trials and clinical applications.

The best postoperative adjuvant therapy for patients with early stage cervical adenosquamous carcinoma

Background

Cervical adenosquamous carcinoma (ASC) was previously thought to be a subtype of cervical adenocarcinoma, but recent studies have found that the clinical features of the two diseases are different. Moreover, the pathological characteristics, survival, prognosis, and optimal ASC therapy remain unknown. This study aims to retrospectively analyze the postoperative survival of patients with early-stage ASC and to evaluate their condition after treatment with postoperative concurrent chemoradiotherapy (CCRT) and prophylactic irradiation of the para-aortic lymphatic drainage area.

Methods

This study enrolled 131 patients with pathologically confirmed ASC screened from 3502 patients with confirmed stage I–II cervical cancer diagnosis who had completed surgical treatments in our hospital. Among the 131 enrolled patients, 75 patients received CCRT, 33 patients received chemotherapy (CT), and 23 patients did not receive adjuvant treatment (named surgery alone (S alone). Of the 75 patients CCRT, 43 patients received prophylactic irradiation of the para-aortic lymphatic drainage area. The efficacy of the postoperative treatments of patients among groups (CCRT, CT, and S alone) was compared.

Results

The median follow-up time, age, and overall survival (OS) were 76 months, 43 years, and 74 months, respectively. The 3- and 5-year survival rates were 82% and 71.4%, respectively. The median disease-free survival (DFS) was 64 months. Cox regression analysis showed that postoperative adjuvant treatment modalities and positive lymph node metastases were associated with OS and DFS. Patients who received CCRT treatment had higher OS and DFS than those with CT and S alone. Prophylactic irradiation of the para-aortic lymphatic drainage area did not improve the OS and DFS of patients with CCRT treatment. However, further subgroup analysis suggested that it might improve survival rates in patients who had positive pelvic lymph nodes as confirmed by postoperative pathology.

Conclusion

Postoperative CCRT improved the survival rates in patients with early-stage ASC. The value of prophylactic irradiation of the para-aortic lymphatic drainage area remains debatable, but it may benefit patients with pelvic lymph node involvement.

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

PURPOSE

To validate the nodal center coverage (NCC) of the three mainstream delineation methods of para-aortic nodal clinical target volume (CTV) and propose a modified delineation method of para-aortic nodal CTV in prophylactic extended-field irradiation (EFI) of cervical cancer.

METHODS

A total of 106 patients with para-aortic lymph nodes (PALNs) identified on PET/CT were included at Peking Union Medical College Hospital between 2011 and 2020. PALNs were classified as left lateral para-aortic (LLPA), aorto-caval (AC), and right para-caval (RPC). Distances from the nodal center to the aorta and inferior vena cava (IVC) were measured. The NCC of the three mainstream delineation methods of para-aortic nodal CTV (CTV-K, CTV-S, and CTV-D) and a modified CTV (CTV-M) was calculated. Radiotherapy plans were created based on 4 CTVs for 10 selected patients who received prophylactic EFI. The chi-squared test and the Student's t-test were performed.

RESULTS

We identified 344 PALNs (216 LLPA, 101 AC, and 27 RPC) in 106 patients. Mean distance from the nodal center to the aorta was 9.6 mm in the LLPA and 7 mm in the AC and from the nodal center to the IVC was 5.6 mm in the AC and 5.6 mm in the RPC. CTV-D improved the NCC of 98% compared with 92% for CTV-K (p = 0.002) and 95% for CTV-S (p = 0.046). CTV-M provided the same satisfactory NCC as CTV-D (97% vs. 98%, p = 0.485). The V_50Gy to the duodenum, the D_mean to the bilateral kidneys, and the V_45Gy to the small bowel were significantly lower on the CTV-M-based plan than on the CTV-D-based plan (p = 0.001, 0.011, and 0.001, respectively).

CONCLUSION

CTV-D provided more satisfactory NCC than CTV-K and CTV-S. CTV-M provided the same satisfactory NCC as CTV-D and reduced the dose to the critical structures.

Clinical Observation of Prophylactic Extended-Field Intensity-Modulated Radiation Therapy with Synchronous Chemotherapy in Locally Advanced Cervical Cancer

BACKGROUND We aimed to evaluate the value of prophylactic extended-field intensity-modulated radiation therapy (IMRT) in the treatment of locally advanced cervical cancer with multiple pelvic lymph node metastases (≥2) and negative common iliac and paraaortic lymph nodes. MATERIAL AND METHODS Thirty-four patient with newly diagnosed cervical cancer (IB1-IVA) and multiple pelvic lymph node metastases (≥2) confirmed by computed tomography and magnetic resonance imaging were randomly divided into an extended-field group (17 patients) and a pelvic-field group (17 patients). In the extended-field group, we added the drainage area of paraaortic lymph nodes on the pelvic field. The pelvic field was administered Dt 45.0 to 50.4 Gy, while the drainage area of paraaortic lymph nodes was administered Dt 40.0 to 45.0 Gy. Both groups were given Irl92 intracavitary radiotherapy after 3 weeks of external irradiation. The total dose of point A was 25.0 to 30.0 Gy, fractional 6.0 to 7.0 Gy. All patients had concurrent platinum-based chemotherapy once weekly until the end of radiotherapy. RESULTS No paraaortic lymph node metastasis was found in the extended-field group (P=0.0184), and disease-free survival (DFS) was prolonged (P=0.0286). Adverse effects in patients with III-IV degree myelosuppression were increased in the extended-field group (P=0.0324). However, all patients recovered after symptomatic treatment. CONCLUSIONS Prophylactic extended-field IMRT with chemotherapy reduced the metastasis rate of paraaortic lymph nodes and prolonged the DFS in patients with locally advanced cervical cancer and multiple pelvic lymph node metastases (≥2), while the toxic adverse effects were tolerated.

Higher Dose to Organs at Risk: The Unintended Consequences of Intravenous Contrast Use in Computed Tomography Simulation for Cervical Cancer

PURPOSE

To compare the volumes of interest and doses to the organs at risk on contrast and noncontrast scans in patients with cervical cancer who underwent prophylactic extended-field radiation therapy (EFRT).

METHODS AND MATERIALS

We reviewed twenty cervical cancer patients treated with prophylactic EFRT at Peking Union Medical College Hospital between March 2021 and April 2021. Each patient underwent noncontrast and contrast scans during simulation. All structures were contoured, and radiation therapy plans were created based on both scans. Student t test and Pearson correlation coefficient test were performed.

RESULTS

Compared with the noncontrast scan, on the contrast scan, the mean volume of the inferior vena cava expanded by 44% (P ≤ .001), and the mean volume of the para-aortic nodal clinical target volume increased by 17% (P ≤ .001). For the second portion of the duodenum, the V30 (38.2% vs 43.8%, P = .038), V35 (27.6% vs 35.1%, P = .002), V40 (18.3% vs 26.3%, P = .014), V45 (11.2% vs 18.5%, P = .008), and V50 (4.2% vs 9.1%, P = .005) were significantly lower on the noncontrast scan than on the contrast scan. For the third portion of the duodenum, the V45 (78.4% vs 81.6%, P = .03) and V50 (59.7% vs 67%, P ≤ .001) were significantly lower on the noncontrast scan than on the contrast scan. For the right kidney, the V5, V10, V15, V20, and V25 on the contrast and noncontrast scans were 85.4% versus 79.8% (P = .013), 52.5% versus 45.6% (P = .021), 25.6% versus 20.1% (P = .003), 11.1% versus 7.5% (P = .001), and 3.8% versus 2.3% (P = .027), respectively.

CONCLUSIONS

Compared with the noncontrast scan, expansion of the inferior vena cava on the contrast scan can lead to excessive contouring and an overdose to the duodenum and right kidney in cervical cancer patients treated with prophylactic EFRT.

Preliminary survey of 3D image-guided brachytherapy for cervical cancer at representative hospitals in Asian countries

3D image-guided brachytherapy (3D-IGBT) has become a standard therapy for cervical cancer. However, the use of 3D-IGBT is limited in East and Southeast Asia. This study aimed to clarify the current usage patterns of 3D-IGBT for cervical cancer in East and Southeast Asia. A questionnaire-based survey was performed in 11 countries within the framework of the Forum for Nuclear Cooperation in Asia. The questionnaire collected the treatment information of patients with cervical cancer who underwent 3D-IGBT. The cumulative external beam radiotherapy and 3D-IGBT doses were summarized and normalized to a biological equivalent dose of 2 Gy per fraction (EQD2) using a linear-quadratic model. Of the 11 institutions representing the participating countries, six (55%) responded to the questionnaire. Overall, data of 36 patients were collected from the six institutions. Twenty-one patients underwent whole-pelvic irradiation and 15 underwent whole-pelvic irradiation with central shielding. Patients received a median of four treatment sessions of 3D-IGBT (range, 2-6). All 3D-IGBT sessions were computed tomography (CT)-based and not magnetic resonance image-based. The median doses to the high-risk clinical target volume D90, bladder D2cc, rectum D2cc and sigmoid colon D2cc were 80.9 Gy EQD2 (range, 58.9-105.9), 77.7 Gy EQD2 (range, 56.9-99.1), 68.0 Gy EQD2 (range, 48.6-90.7) and 62.0 Gy EQD2 (range, 39.6-83.7), respectively. This study elucidated the current patterns of 3D-IGBT for the treatment of cervical cancer in East and Southeast Asia. The results indicate the feasibility of observational studies of CT-based 3D-IGBT for cervical cancer in these countries.