Postoperative Radiotherapy In Patients Research Articles

Survival benefits of postoperative radiotherapy in patients with cT1 − 2N1M0 breast cancer after neoadjuvant chemotherapy: a SEER-based population study

BackgroundWhether patients with cT1 − 2N1M0 breast cancer can benefit from postoperative radiotherapy (RT) after receiving neoadjuvant chemotherapy (NAC) has been controversial. Therefore, the purpose of this study was to explore whether postoperative RT can benefit this group of patients in terms of survival.MethodsWe used Surveillance, Epidemiology, and End Results (SEER) data to conduct a retrospective review of women with cT1 − 2N1M0 breast cancer diagnosed between 20 and 80 years of age who received NAC between 2010 and 2015. Our study compared the impact of postoperative RT on overall survival (OS) and cancer-specific survival (CSS) in breast cancer patients using propensity score matching (PSM) and performed subgroup analysis.ResultsThis study finally included 1092 cT1 − 2N1M0 breast cancer patients. Regardless of the patient’s PSM status, postoperative RT was significantly associated with OS of cT1-2N1M0 breast cancer patients who received NAC. Specifically, the 10-year OS rate was 78.7% before PSM matching, compared with 71.1% in patients who did not receive postoperative RT, and the difference was more significant after PSM matching, which was 83.1% and 71.1% respectively. However, postoperative RT did not significantly benefit CSS in patients with cT1 − 2N1M0 breast cancer who received NAC. The 10-year CSS rate was 81.4% VS 76.2% (P = 0.085) before PSM matching and 85.8% VS 76.2%(P = 0.076) after matching. Due to the intersection of OS and CSS curves, this restricted mean survival time (RMST) method was chosen as a supplement. After 60 months, the OS difference in RMST between the postoperative RT group and the non-radiotherapy (noRT) group was 7.37 months (95%CI: 0.54–14.21; P = 0.034), and the CSS difference was 5.18 months (95%CI: -1.31-11.68; P = 0.118). Subgroup analysis found that in patients with right-sided breast cancer, postoperative RT improved the patient’s OS (HR = 0.45, 95%CI: 0.21–0.95, P = 0.037) and CSS (HR = 0.42, 95%CI: 0.18–0.98, P = 0.045).ConclusionsOur results showed that additional postoperative RT improved the OS of cT1 − 2N1M0 breast cancer patients who received NAC, but failed to improve their CSS. It is worth noting that in the subgroup analysis of patients with right-sided breast cancer, we observed significant improvements in OS and CSS. And further prospective studies are still needed to verify the effect of postoperative RT in different subgroups.

Preoperative CT-based radiomic prognostic index to predict the benefit of postoperative radiotherapy in patients with non-small cell lung cancer: a multicenter study

BackgroundThe value of postoperative radiotherapy (PORT) for patients with non-small cell lung cancer (NSCLC) remains controversial. A subset of patients may benefit from PORT. We aimed to identify patients with NSCLC who could benefit from PORT.MethodsPatients from cohorts 1 and 2 with pathological Tany N2 M0 NSCLC were included, as well as patients with non-metastatic NSCLC from cohorts 3 to 6. The radiomic prognostic index (RPI) was developed using radiomic texture features extracted from the primary lung nodule in preoperative chest CT scans in cohort 1 and validated in other cohorts. We employed a least absolute shrinkage and selection operator-Cox regularisation model for data dimension reduction, feature selection, and the construction of the RPI. We created a lymph-radiomic prognostic index (LRPI) by combining RPI and positive lymph node number (PLN). We compared the outcomes of patients who received PORT against those who did not in the subgroups determined by the LRPI.ResultsIn total, 228, 1003, 144, 422, 19, and 21 patients were eligible in cohorts 1–6. RPI predicted overall survival (OS) in all six cohorts: cohort 1 (HR = 2.31, 95% CI: 1.18–4.52), cohort 2 (HR = 1.64, 95% CI: 1.26–2.14), cohort 3 (HR = 2.53, 95% CI: 1.45–4.3), cohort 4 (HR = 1.24, 95% CI: 1.01–1.52), cohort 5 (HR = 2.56, 95% CI: 0.73–9.02), cohort 6 (HR = 2.30, 95% CI: 0.53–10.03). LRPI predicted OS (C-index: 0.68, 95% CI: 0.60–0.75) better than the pT stage (C-index: 0.57, 95% CI: 0.50–0.63), pT + PLN (C-index: 0.58, 95% CI: 0.46–0.70), and RPI (C-index: 0.65, 95% CI: 0.54–0.75). The LRPI was used to categorize individuals into three risk groups; patients in the moderate-risk group benefited from PORT (HR = 0.60, 95% CI: 0.40–0.91; p = 0.02), while patients in the low-risk and high-risk groups did not.ConclusionsWe developed preoperative CT-based radiomic and lymph-radiomic prognostic indexes capable of predicting OS and the benefits of PORT for patients with NSCLC.

Lymphocytopenia following adjuvant radiotherapy for breast cancer

AbstractObjectiveWe retrospectively analyzed breast cancer patients who received adjuvant radiotherapy to determine the incidence of lymphocytopenia and its risk factors.MethodsWe reviewed 812 patients with breast cancer who received postoperative radiotherapy. Patients were divided into two groups based on the use of chemotherapy, and a generalized linear regression model was used to explore predictive factors for grade 2 or higher lymphocytopenia. We also examined the effect of lymphocytopenia on overall survival.ResultsGrade 2 or higher lymphocytopenia was observed in 19.4% of patients who did not receive chemotherapy and 45.1% of patients who received chemotherapy. In multivariate analysis, bilateral disease, regional lymph node irradiation, and baseline lymphocytopenia were associated with lymphocytopenia in patients who did not receive cytotoxic chemotherapy. Regional lymph node irradiation, baseline lymphocytopenia, use of antimetabolites, and use of molecular‐targeted agents were associated with lymphocytopenia in patients treated with chemotherapy. In the survival analysis, lymphocytopenia was associated with worse overall survival only in patients treated with cytotoxic chemotherapy (p = 0.039), and not in patients who did not receive chemotherapy (p = 0.77).ConclusionThe analysis revealed the incidence and risk factors of lymphocytopenia after postoperative radiotherapy in patients with breast cancer.

Excellent long-term pain response and local control following postoperative radiotherapy in patients with multiple myeloma.

Multiple myeloma is associated with osteolytic bone lesions, often requiring surgery of the spine and postoperative radiotherapy (RT). Although common, data for clinical and informed decision-making are sparse. In this monocentric retrospective study, we aim to report the outcome of patients who underwent spinal surgery and postoperative RT due to multiple myeloma. Atotal of 54patients with multiple myeloma who underwent prior spinal surgery and postoperative RT at our institution between 2009 and 2020 were analyzed. Spinal instability neoplastic score (SINS) and Bilsky score, posttherapeutic adverse events, clinical data, and outcomes were collected and analyzed. The primary endpoint of this study was overall survival (OS), secondary endpoints were progression-free survival (PFS), pain response, local control, and skeletal-related events (SRE). The 3‑ and 5‑year overall survival (OS) was 74.9% (95% confidence interval [CI]: 63.5-88.4%) and 58% (95% CI: 44.5-75.6%), respectively. Median survival was not reached and 75% survival was 34.3months (95% CI: 28.7-95.4 months). Median follow-up was 63months (95% CI: 49-94months). The number of patients with good to adequate performance status (Karnofsky performance score [KPS] ≥ 70) significantly increased after surgery (p < 0.01). We observed no grade3/4 toxicity and only 13 (24%) grade1/2 adverse events. Two patients (4%) experienced SRE. Overall, 92% of patients reported reduced pain after radiotherapy, with 66% reporting complete pain response. There was no difference in pain response between patients with different Bilsky scores. Bisphosphonate therapy and lower Bilsky score at the start of RT were associated with improved OS in univariate analysis (all p < 0.05). Multivariate Cox regression confirmed aBilsky score of2 or3 as an independent negative prognostic factor (HR 3.89; 95CI 1.4-10.7; p < 0.01). We observed no in-field recurrences. In this study, we were able to show that the current standard of RT after spinal surgery of osteolytic lesions is safe. In addition, we observed avery low rate of SRE (4%) and no in-field recurrences, demonstrating the local efficacy of RT in multiple myeloma patients. Higher Bilsky scores were associated with worse OS in multivariate analysis, but had no effect on pain response.

The effect of radiotherapy on patients with pathological stage IIB breast cancer after breast-conserving surgery or mastectomy: A cohort study.

Breast cancer is one of the most common cancers in women, and treatment options include surgery, systemic therapies, and radiotherapy (RT). While postoperative RT plays an important role in reducing local recurrence rates and improving survival outcomes, its exact impact on patients with pathological stage IIB breast cancers remains unidentified. In this retrospective cohort study, patients with newly diagnosed pathological stage IIB breast cancer who underwent surgery and postoperative RT were included. The data were collected from medical records, and survival outcomes were assessed using the Kaplan-Meier method, log-rank tests, and Cox regression models. In total, 350 patients participated in this study. Overall survival, locoregional recurrence-free survival, event-free survival, and distant metastasis-free survival rates did not significantly differ between those who received RT and those who did not. Multivariate analyses revealed that patients who received anthracycline or taxane chemotherapy had better survival outcomes. Our findings demonstrated that postoperative RT had no significant effect on overall survival, locoregional recurrence, event-free survival, or distant metastasis rates in patients with pathological stage IIB breast cancer. However, anthracycline- and taxane-based chemotherapies were associated with improved outcomes. These findings demonstrated the complexities of treating such patient populations with multimodal therapies. Further research is needed to ensure optimal postoperative RT in patients with pathological stage IIB breast cancer. Clinicians must consider individual patient characteristics and incorporate comprehensive treatment approaches to ensure successful outcomes in this population.

Comparison of the incidence of wound complications with preoperative and postoperative radiotherapy in patients with extremity soft tissue sarcoma resection: A meta-analysis.

We performed a meta-analysis to compare the effect of preoperative and postoperative radiotherapy on wound complications after resection of extremity soft tissue sarcoma (ESTS). A comprehensive computerised search of the PubMed, Cochrane Library, Web of Science, EMBASE, China National Knowledge Infrastructure (CNKI), VIP, and Wanfang databases was conducted from their inception to August 2023 to identify studies comparing the effect of preoperative and postoperative radiotherapy on wound complications after ESTS resection. Two investigators independently screened the literature, extracted the data, and assessed the quality of the articles. The meta-analysis was performed using RevMan 5.4 software. Nine studies with 1271 patients were included, with 631 and 640 patients in the preoperative and postoperative radiotherapy groups, respectively. The results showed that the incidence of postoperative wound complications after ESTS resection was significantly higher with preoperative radiotherapy than with postoperative radiotherapy (27.26% vs. 12.03%, odds ratio [OR]: 2.88, 95% confidence interval [CI]: 2.12-3.91, p < 0.001). However, the rate of local recurrence of ESTS was significantly lower with preoperative radiotherapy than with postoperative radiotherapy (8.75% vs. 14.81%, OR: 0.57, 95% CI: 0.36-0.91, p = 0.02), and the 3-year overall survival was significantly higher in the preoperative radiotherapy group than in the postoperative radiotherapy group (82.24% vs. 70.04%, OR: 1.97, 95% CI: 1.05-3.71, p = 0.03). This pooled analysis suggests that although preoperative radiotherapy increases the rate of wound complications in ESTS compared with postoperative radiotherapy, it significantly reduces the rate of local recurrence after ESTS resection and improves the overall survival of patients. Owing to the limitations in the number and quality of the included studies, additional prospective cohort studies or randomised controlled trials are required to confirm these findings.

Integration of Multiparameter MRI into Conventional Pretreatment Risk Factors to Predict Adverse Features after Radical Prostatectomy.

The purpose of this study was to Integration of Multiparameter MRI into conventional pretreatment risk factors to develop nomogram for the prediction of adverse features (i.e., positive margin (PM) or extra-prostatic extension (EPE)) indicated for postoperative radiotherapy in patients with prostate cancer. We analyzed 203 histologically proven prostate cancer patients underwent preoperative 3T multiparametric MRI including high b value (0, 1500 s/mm2) diffusion-weighted imaging between 2019 and 2022 at our hospital. Patients with a history of neoadjuvant hormonal therapy, or patients whose surgeon's experience was ≤3 years were excluded. Age, surgical technique, serum PSA level, PSA density, clinical T stage, and biopsy Gleason score were clinical predictors. MRI parameters include prostate volume, tumor size, ECE score, seminal vesicle invasion score, tumor location (apex, peripheral region, or bladder neck), apparent diffusion coefficient (ADC), tumor contact length (TCL), PI-RADS score. Predictors were used in nomograms developed from multivariable logistic regression analysis to estimate the probability of positive margin (PM) or extra-prostatic extension (EPE) after RP. The nomogram's predictive accuracy and discriminative ability were determined by the concordance index with calibration and receiver operating characteristic (ROC) curves. (1) Patient characters: Table 1 lists the MRI characteristics of the patients. Median PSA level is 17.6ng/ml. All patients received extra-fascial resection. 44% of the patients underwent robotic surgery. 24% of the patients had positive margins. In 226 patients who was clinically confined to the prostate, 100 (44%) had a postoperative pathological upgrade of pT3a or above. 46 (29%) of the 158 patients with biopsy grade group (GG)1 was confirmed GG3-5 after RP. Using mpMRI parameters and clinicopathological information, we produced nomograms that may accurately predict adverse Features that are indications for postoperative radiotherapy after RP, which may help individualize treatment decision-making.

Matched-pair analysis of the impact of low-dose postoperative radiotherapy on prognosis in patients with advanced hypopharyngeal squamous cell carcinoma without positive surgical margins and extracapsular extension.

We conducted a comparative analysis between low and high-dose postoperative radiotherapy in patients with hypopharyngeal squamous cell carcinoma (HPSCC) in stage III or IV without positive surgical margins and extracapsular extension (ECE). Propensity score matching (PSM) was used to eliminate confounding factors and reduce bias. The matched-pair analysis included 156 patients divided into two groups: the low-dose radiotherapy group (LD-RT 50 Gy, 78 cases) and the high-dose radiotherapy group (HD-RT 60 Gy, 78 cases). Both cohorts were statistically comparable in terms of age, gender, subsite, and TNM classification. The median follow-up time was 49 months (ranging from 5 to 100 months). The overall survival (OS) rate, progression-free survival (PFS) rate, locoregional control rate (87% vs. 85.7%; p = 0.754), distant metastases-free survival (79.2% vs. 76.6%; p = 0.506), and the occurrence of second primary tumors (96.1% vs. 93.5%; p = 0.347) showed no significant differences between the LD-RT group and the HD-RT group. The 3-year OS was 64.9% and 61% in the low-dose and high-dose group, respectively, and 63% in the entire group (p = 0.547). The 3-year PFS was 63.6% and 54.5% (p = 0.250), respectively, and the 3-year PFS of the entire group was 59.1%. Multivariate analyses revealed that pathological T and N classification, and pathological differentiation were associated with 3-year OS, PFS, and LRFS and were independent prognostic factors (p < 0.05). LD-RT was not associated with an increased risk of death and disease progression compared to HD-RT. The results of postoperative low-dose radiotherapy did not show inferiority to those of high-dose radiation for patients with advanced hypopharyngeal cancer without positive surgical margins and ECE in terms of OS, PFS, locoregional control, and metastases-free survival.

Comparison of pre-operative and post-operative radiotherapy in patients with localized myxoid liposarcoma.

Myxoid liposarcoma is more radiosensitive than other soft tissue sarcomas, and radiotherapy has been reported to reduce tumour size. This study was performed to compare the rates of local recurrence, survival and wound complications between pre- and post-operative radiotherapy for localized myxoid liposarcoma. From the Japanese Nationwide Bone and Soft Tissue Tumor Registry database, 200 patients with localized myxoid liposarcoma who received pre- (range, 30-56Gy) or post-operative (range, 45-70Gy) radiotherapy and surgery were included in this retrospective study. Propensity score matching was used to adjust for background differences between patients who received pre- and post-operative radiotherapy. Local recurrence occurred in five (5.0%) and nine (9.0%) patients in the pre- and post-operative radiotherapy groups, respectively (both n=100). The median follow-up time from diagnosis was 40.5months (IQR, 26.3-74). Univariate analysis showed a similar risk of local recurrence between the pre- and post-operative radiotherapy groups (5-year local recurrence-free survival 94.9% [95% CI 87.0-98.1] vs. 89.0% [95% CI 79.6-94.3]; P=0.167). Disease-specific survival was similar between the pre- and post-operative radiotherapy groups (5-year disease-specific survival 88.1% [95% CI 75.5-94.6] vs. 88.4% [95% CI 77.3-94.5]; P=0.900). The incidence of wound complications was similar between the pre- and post-operative radiotherapy groups (7.0% vs. 12.0%; P=0.228). There was no difference in local recurrence, survival or incidence of wound complications between pre- and post-operative radiotherapy for localized myxoid liposarcoma. Therefore, pre-operative radiotherapy for myxoid liposarcoma provides clinical results equivalent to post-operative radiotherapy.

Efficacy and prognosis of adjuvant treatment of endometrial cancer with medroxyprogesterone acetate COX regression analysis.

Endometrial cancer is one of the most commonly diagnosed gynecological cancers worldwide, and early-stage high-risk endometrial cancer has a poor prognosis. Adjuvant treatments after surgery, such as chemotherapy and radiotherapy, have been widely used in clinical practice to improve patient survival. Medroxyprogesterone acetate is a synthetic progestogen that has been reported to have potential anticancer effects in endometrial cancer. However, its efficacy, safety, and long-term prognostic benefits as an adjuvant treatment for endometrial cancer remain controversial. Therefore, this study aimed to observe the efficacy and prognostic impact of adjuvant medroxyprogesterone acetate treatment in patients with early-stage high-risk endometrial cancer and evaluate its safety. To observe the efficacy and prognosis of adjuvant treatment of endometrial cancer with medroxyprogesterone acetate and to evaluate its safety. We collected the clinical data of 200 patients with early-stage high-risk endometrial cancer who were admitted to the Department of Obstetrics and Gynecology of our hospital from January 2018 to December 2022. The control group (100 patients) underwent conventional surgical treatment, and the study group (100 patients) was administered adjuvant medroxyprogesterone acetate tablets on top of the control group. The Kaplan-Meier curve analysis and log-rank test were performed to determine the possible factors influencing the 5-year cumulative survival rate in the patients. The Cox regression analysis was performed to identify the factors influencing the survival prognosis of endometrial cancer. According to the Cox regression analysis, age [hazard ratio (HR) = 4.636, 95% confidence interval (95%CI): 1.411-15.237], pathological type (HR = 6.943, 95%CI: 2.299-20.977), molecular typing (HR = 5.789, 95%CI: 3.305-10.141), and myometrial infiltration (HR = 5.768, 95%CI: 1.898-17.520) were factors influencing the prognosis of patients with early-stage high-risk endometrial cancer. Age, pathological type, molecular typing, and myometrial infiltration were all relevant factors affecting the prognosis of early-stage high-risk endometrial cancer. The potential long-term prognostic benefit of adjuvant postoperative radiotherapy in patients with early-stage high-risk endometrial cancer is worthy of clinical consideration.

Novel Intrafraction Motion Tracking During Postoperative Spine Stereotactic Irradiation for a Patient With Carbon Fiber Fixation Hardware

Carbon-fiber reinforced (CFR) polyetheretherketone hardware is an alternative to traditional metal hardware used for spinal fixation surgeries before postoperative radiation therapy for patients with spinal metastases. CFR hardware's radiolucency decreases metal artifact, improving visualization and accuracy of treatment planning. We present the first clinical use and proof of principle of CFR spinal hardware with tantalum markers used for successful tracking of intrafraction motion (IM) using Varian TrueBeam IMR (Intrafraction Motion Review) software module during postoperative spine stereotactic radiation. A 63-year-old woman with history of endometrial cancer presented with acute back pain. Imaging demonstrated pathologic T12 vertebral fracture with cord compression. She underwent T12 vertebrectomy with circumferential decompression and posterior instrumented T10-L2 fusion at our facility using CFR-polyetheretherketone hardware with tantalum screw markers followed by postoperative stereotactic body radiation therapy to 3000 cGy in 5 fractions delivered to T11-T12. Tantalum screw markers were used for IMR tracking. During irradiation, 260 kV images were acquired, and IMR software was able to identify and track markers. During the entire treatment, the IM motions were less than 3 mm. This is the first presented case of CFR spinal hardware with tantalum markers used for successful IMR tracking of IM during daily spine stereotactic treatment. Future work will be needed to improve workflow and create a spine-specific IMR protocol.

Individualized prediction of survival benefit from postoperative radiotherapy for patients with malignant pleural mesothelioma.

The role of postoperative radiotherapy (PORT) in malignant pleural mesothelioma (MPM) remains controversial and the eighth edition TNM staging scheme for MPM has not been fully verified. We aimed to develop an individualized prediction model for identifying optimal candidates for PORT among MPM patients who received surgery plus chemotherapy and externally validate the performance of the new TNM staging scheme. Detailed characteristics of MPM patients during 2004-2015 were retrieved from SEER registries. Propensity score matching (PSM) was conducted to reduce disparities of baseline characteristics (age, sex, histologic type, stage, and type of surgery) between the PORT group and no-PORT group. A novel nomogram was constructed based on independent prognosticators identified by multivariate Cox regression model. The discriminatory performance and degree of calibration were evaluated. We stratified patients into different risk groups according to nomogram total scores and estimated the survival benefit of PORT in different subgroups in order to identify the optimal candidates. We identified 596 MPM patients, among which 190 patients (31.9%) received PORT. PORT conferred significant survival benefit in the unmatched population, while there was no significant survival difference favoring PORT in the matched population. The C-index of the new TNM staging scheme was closed to 0.5, which represented a poor discriminatory ability. A novel nomogram was constructed based on clinicopathological factors, including age, sex, histology, and N stage. We stratified patients into three risk groups. Subgroup analyses indicated that PORT was beneficial for high-risk group (p = 0.003) rather than low-risk group (p = 0.965) and intermediate-risk group (p = 0.661). We established a novel predictive model, which could make individualized prediction of survival benefit of PORT for MPM and could compensate for weakness in TNM staging system.

Determining the survival benefit of postoperative radiotherapy in patients with pT1-3N1M0 rectal cancer undergoing total mesorectal excision: a retrospective analysis

BackgroundThe National Comprehensive Cancer Network guidelines recommend routine postoperative adjuvant radiotherapy and chemotherapy for patients with stage III rectal cancer who do not receive neoadjuvant therapy before surgery. The present study aimed to evaluate the value of postoperative radiotherapy in patients with low-risk disease (pT1-3N1M0) who did not receive neoadjuvant therapy prior to total mesorectal excision.MethodsWe used the Surveillance, Epidemiology, and End Results database (2004–2016) to retrospectively recruit patients with pT1-3N1M0 rectal cancer whose initial treatment was radical surgery with postoperative adjuvant chemotherapy. A propensity score model was used to balance the baseline covariates.ResultsOf the 2012 patients included in the present study, 1384 received adjuvant chemoradiotherapy (radio group), whereas the remaining 718 received chemotherapy alone (no-radio group). There was no significant difference in cancer-specific survival rate between the two groups (log-rank test χ2 = 2.372, P = 0.124) in the overall sample. Additionally, in the propensity score−matched cohort, adjuvant radiotherapy did not improve cancer-specific survival. Subgroup analysis showed that having three positive lymph nodes and a tumor > 50 mm, combined with postoperative adjuvant chemotherapy, could lead to an improved tumor-specific survival rate, while other cases did not benefit from postoperative radiotherapy.ConclusionsFor patients with pT1-3N1M0 rectal cancer who did not receive neoadjuvant therapy before surgery, postoperative radiotherapy in addition to adjuvant chemotherapy did not significantly improve survival rates. The number of positive nodes (n = 3) and tumor size (> 50 mm) were found to be potential screening indicators for postoperative adjuvant radiotherapy.

Cost-effectiveness analysis of (accelerated) pre-operative versus (conventional) post-operative radiotherapy for patients with oral cavity cancer in Sweden

BackgroundTreatment for resectable oral cavity cancer (OCC) often includes combinations of surgery and radiotherapy (RT), but there is no conclusive information on the preferred treatment order. The aim of this study was to assess the costs and cost-effectiveness of two alternative treatment regimens for patients with OCC, reflecting pre- and post-operative RT, from a societal perspective.MethodsThe study used data from the ARTSCAN 2 randomised controlled trial, which compares pre-operative accelerated RT with post-operative conventionally fractionated RT. Two-hundred-forty patients were included in the analysis of treatment outcomes. Direct costs were retrieved from the hospital’s economic systems, while indirect costs were obtained from national registries. Cost-effectiveness was assessed and a sensitivity analysis was performed. Overall survival (OS) at 5 years, was used as effect measure in the analysis.ResultsTwo-hundred-nine patients completed the treatments and had retrievable data on costs. Mean direct costs (inpatient and outpatient care) were € 47,377 for pre-operative RT and € 39,841 for post-operative RT (p = 0.001), while corresponding indirect costs were € 19,854 and € 20,531 (p = 0.89). The incremental cost, i.e., the mean difference in total cost between the treatment regimens, was € 6859 paralleled with a 14-percentage point lower OS-rate at 5 years for pre-operative RT (i.e., 58 vs. 72%). Thus, pre-operative RT was dominated by post-operative RT.ConclusionsFrom a societal perspective, post-operative RT for patients with resectable OCC is the dominant strategy compared to pre-operative RT.

Comparative analysis of pre- and postmenopausal endometrial cancer in 216 patients.

Endometrial carcinoma (EC) is one of the most common gynecological malignancies and has become more prevalent in recent decades. The clinical manifestations and characteristics of EC in premenopausal and postmenopausal women differ and present with distinct pathological stages and subtypes of EC. Surgery remains the principal therapeutic approach, but the postoperative prognosis is largely affected by the pathological state. A retrospective study was conducted on 216 patients with EC who were hospitalized from August 2008 to August 2019 in Wuhan Union Hospital. The patients were divided into 2 groups based on the pre- or postmenopausal occurrence of EC. The general clinical characteristics, intraoperative situation, clinicopathological data, and postoperative outcomes of the 2 groups were compared. Patients with premenopausal EC had earlier menarche, a higher incidence of primary infertility and anemia, and fewer pregnancies and deliveries. Patients with postmenopausal EC were older and often had hyperlipidemia and diabetes. Additionally, patients who were postmenopausal had worse tumor pathological gradings, more severe muscular invasion, and a higher rate of lymphatic metastasis. These factors led to a higher demand for postoperative radiotherapy in patients but a lower survival rate. Generally, premenopausal EC differs from postmenopausal EC: the latter is more malignant and has a worse prognosis.

The role of postoperative radiation after radical hysterectomy for women with early-stage neuroendocrine carcinoma of the cervix: A meta-analysis

IntroductionNeuroendocrine carcinoma of the cervix (NECC) is an aggressive disease with high rates of nodal disease spread even in seemingly cervix-confined disease. Many providers routinely prescribe postoperative radiation therapy in an effort to reduce recurrences despite a lack of supporting studies. The objective of this study was to determine recurrence and mortality in patients with early-stage NECC who had pelvic radiation after radical hysterectomy compared to those who did not receive radiation. MethodsWe performed a meta-analysis of 13 unique studies that reported recurrence and/or mortality for patients with early-stage NECC who underwent radical hysterectomy with or without adjuvant radiation therapy. ResultsIn 5 studies that reported overall recurrence rates, 63 (52.5%) of 120 patients who received postoperative radiation recurred compared to 70 (37.8%) of 185 patients who did not (RR 1.21, 95% CI: 0.85–1.70, p = 0.29). In 5 studies that reported pelvic recurrence rates, there were 15 pelvic recurrences (12.5%) in the 120 patients who received postoperative radiation compared to 45 pelvic recurrences (24.3%) in the 185 patients who did not (RR 0.60, 95% CI: 0.34–1.08, p = 0.09). In 13 studies that reported mortality rate, there were 138 deaths (34.8%) in 396 patients who received postoperative radiation therapy compared to 223 (35.2%) in 632 patients who did not (RR 1.08, 95% CI: 0.75–1.56, p = 0.66). ConclusionsThe addition of routine postoperative radiation therapy in all patients with early-stage NECC after radical hysterectomy may reduce pelvic recurrences but does not appear to decrease overall recurrence or death. However, there may still be a role for postoperative radiation therapy in patients with additional high-risk pathologic factors.

Long-term oncological outcomes of organ-sparing treatment of patients with early breast cancer aged 65 years and older who had no postoperative radiation therapy

Postoperative radiation therapy after breast-conserving surgery is a standard method of treating breast cancer, but recently the issue of its de-escalation in patients older than 65 due to concomitant pathology, lower life expectancy and possible development of post-radiation complications has been discussed. The results of some foreign studies prove the absence of a statistically significant difference in relapse-free and overall survival in patients with early breast cancer older than 65 years with relatively favorable clinical and morphological characteristics without postoperative radiation therapy. We analyzed the long-term oncological results in patients with breast cancer older than 65 years after breast-conserving surgery without postoperative radiation therapy. The results of the study showed that postoperative radiation therapy in patients over 65 years of age with stage IA pT1N0M0 breast cancer of luminal immunophenotype A does not improve long-term oncological indicators. Thus, the exclusion of postoperative radiation therapy from the treatment plan of this group of patients is oncologically safe and economically justified.

155 (PB-068) Poster - Postoperative breast radiotherapy using deformable image registration of initial PET-CT before NAC

Background: Radiation treatment planning (RTP) is based on the clinical stage at diagnosis and the pathological stage after surgery in postoperative radiotherapy for patients with breast cancer who undergo neoadjuvant chemotherapy (NAC). However, adopting initial PET-CT images for RTP is challenging because of image registration inconsistency due to different acquisition conditions. We compared relevant clinical parameters in between patients who underwent PET-CT under the same conditions as those at the RTP (group A) and those who did not (group B).

A Phase I Study of Adjuvant Niraparib Administered Concurrently with Postoperative Radiation Therapy in Patients with Localized Triple Negative Breast Cancer

<h3>Purpose/Objective(s)</h3> Residual disease after neoadjuvant therapy (NAT) is associated with higher risk of recurrence, including local failure (25%) in triple negative breast cancer (TNBC). Novel combinations that increase the efficacy of standard-of-care treatments on locoregional control are warranted. PARP inhibitors (PARPi) target the DNA damage repair pathway, which is often altered in TNBC, and show promise as radiosensitizers. The objective of this phase I trial (NCT03945721) was to determine the maximum tolerated dose (MTD) of a PARPi, niraparib, in pts with high risk TNBC receiving postoperative radiotherapy (RT). <h3>Materials/Methods</h3> Eligible pts had stage I-III TNBC with residual invasive disease following NAT or primary tumor ≥1 cm after upfront surgery. A 3+3 escalation design was used to test 2 dose levels of QD niraparib (100mg, 200mg) with concurrent RT to the chest wall or breast +/- regional lymph nodes over 4-6 weeks. Dose expansion followed at the MTD. A boost was delivered in pts who had lumpectomy. 2 pts received proton beam RT. Bolus was administered in postmastectomy RT or in cases of dermal lymphatic invasion. Circulating tumor DNA (ctDNA) was collected at baseline, mid-RT, end of RT, and 30 days post-RT to assess the kinetics of ctDNA levels during RT and the association with clinical outcomes. Adverse events (AEs) were assessed using CTCAE v5.0. <h3>Results</h3> 21 pts were enrolled from July 2019 – October 2021. The median age was 49 (31-69). 19/21 pts had residual disease after NAT (6 RCB I, 7 RCB II, 6 RCB III); among them, 2 underwent adjuvant chemotherapy prior to enrolling. The remaining 2/21 pts (pT2N0; pT1cN0) received upfront breast conserving surgery followed by adjuvant chemotherapy. In dose escalation, 6 pts received 100mg niraparib + RT and 2 pts received 200mg niraparib + RT. One DLT in the 100mg cohort (G3 dermatitis) was attributed to RT. Two DLTs in the 200mg cohort (G3 thrombocytopenia) were attributed to niraparib and study drug was discontinued. In dose expansion, 13 pts received 100mg niraparib + RT. G3 AEs were dermatitis (4/21), hematologic (4/21), consisting of thrombocytopenia, anemia & lymphopenia, and elevated alkaline phosphatase (1/21). There was one G4 thrombocytopenia. All skin AEs were attributed to RT and were not exacerbated by niraparib. No pts in dose expansion discontinued treatment due to toxicity. 20/21 went on to standard-of-care capecitabine after completing RT. Results of ctDNA will be reported at the meeting. <h3>Conclusion</h3> The MTD of niraparib + postop RT was determined to be 100mg QD and was associated with a 24% rate of G3-4 hematologic toxicities and 19% rate of G3 radiation dermatitis in pts with localized TNBC, which is within upper limits of normal for pts in whom chest wall/skin is targeted. These results will be informative for a future larger study testing the efficacy of niraparib + postop RT in high risk TNBC.

Development and Validation of a Decision Support Framework to Evaluate the Role of Postoperative Radiotherapy in Patients with Pathological N2 Non-Small Cell Lung Cancer

<h3>Purpose/Objective(s)</h3> Postoperative radiotherapy (PORT) plays a highly controversial role in pN2 NSCLC disease. Recent study revealed that not all patients can benefit from PORT. Further study is needed to identify predictors for PORT. <h3>Materials/Methods</h3> A total of 1044 patients with completely resected pathologic stage T1-3N2M0 NSCLC were analyzed. Risk factors of distant metastasis were identified by the log-rank tests and the multivariable Cox models. The decision support framework (DSF) was built based on the previously published PI model and risk factors of distant metastasis. An independent dataset was used to validate the DSF. <h3>Results</h3> Clinical N2 status (HR=1.227, 95% CI 1.036 to 1.453, P=0.0178) and >4 involved lymph nodes (HR=1.272, 95% CI 1.071 to 1.510, P=0.0058) were identified as independent risk factors of distant metastasis and were also found to be associated with locoregional recurrence (LRR) in our previous work. The high-intermediate-risk histological type (micropapillary or solid positive adenocarcinomas) was found to be associated with distant metastasis (HR=1.207, 95% CI 1.062 to 1.371, P=0.0129), but not associated with LRR. We built an DSF accordingly and stratify patients into four groups: high LRR risk and high-intermediate histological risk (HHR) group, high LRR risk and low histological risk (HLR) group, low LRR risk and high-intermediate histological risk (LHR) group, and low LRR risk and low histological risk (LLR) group. PORT significantly improved OS only in the subgroup with a high risk of LRR and low-risk histological type (3-year OS rates: 66.7% for PORT vs. 50.2% for non-PORT, respectively; P=0.023). In the HHR group, PORT was associated with a not significant increase in OS. In the LLR and the LHR groups, no significant differences in OS were observed between PORT and non-PORT. <h3>Conclusion</h3> This study developed and validated a DSF combining two types of clinicopathological characteristics to predict the outcome of PORT in patients with completely resected pN2 NSCLC individually.