Chemoradiotherapy Group Research Articles

Surgery with adjuvant chemotherapy versus chemoradiation for early-stage large cell neuroendocrine cancer (LCNEC) of the lung: A SEER plus based analysis.

e20616 Background: LCNEC of the lung is a rare and highly aggressive tumor with neuroendocrine differentiation. Given its rare occurrence and lack of data from large randomized trials, treatment recommendations are based on the extrapolation of data, primarily from small-cell lung cancer studies. We conducted this study to evaluate the survival difference among patients with LCNEC with an N1 disease between those who received surgery and adjuvant chemotherapy versus definitive chemotherapy and radiotherapy. Methods: We utilized Surveillance, Epidemiology, and End Results (SEER) plus 18 registries database to identify patients diagnosed with LCNEC with tumor stage of T1, T2, or T3 and nodal stage of N1. The study population included patients, 18 years and above, who underwent surgical resection followed by adjuvant chemotherapy and patients who received definitive chemo-radiotherapy for early stage LCNEC. Kaplan-Meier and log rank test were used to compare overall survival (OS) and Cancer specific survival (CSS). Multivariate survival analysis was done using the cox proportional hazards regression model. Results: A total of 178 patients were included, 57.3% (n = 102) were < 65-year-old, 50.56% (n = 90) were male, mostly Caucasian 87.08% (n = 155) and identified as non-Hispanic 93.26% (n = 166). Out of them, 70.22% (n = 125) underwent surgery plus adjuvant chemotherapy and 29.78% (n = 53) underwent chemoradiation. Patients who underwent surgery with adjuvant chemotherapy had higher overall survival (OS) than chemoradiation (37 vs. 11 months respectively). 3-year (49.9% vs. 15.7%) and 5-year OS rates (36.7% vs. 10.4%) were also higher in the earlier group. On multivariate analysis after adjusting for age, gender, race and origin, patients who received chemoradiation had higher hazards as compared to those who received surgery and adjuvant chemotherapy (Hazard ratio: 2.91, 95% Confidence interval (CI):1.93,4.37, P value < 0.001). When examining the cancer specific survival (CSS), similar results were observed with higher CSS in the surgery with adjuvant chemotherapy group (18 vs. 8 months) reaching a statistical significance of P < 0.001 and higher hazards in chemoradiation group (Hazard ratio: 3.33, 95% Confidence interval (CI):2.09,5.28, P value < 0.001). 3-year survival (26.47% vs. 2.7 %) and 5-year CSS rates (11.76% vs. not reached) were also pronounced in the patients treated with surgery with adjuvant chemotherapy. Conclusions: Our study demonstrates that patients with early stage LCNEC (T1-3 N1) disease treated with surgery and adjuvant chemotherapy had statistically significant overall and cancer specific survival rates compared to those treated with chemoradiation.

Radiotherapy alone versus concurrent or adjuvant chemoradiotherapy for nasopharyngeal carcinoma patients with negative Epstein-Barr virus DNA post-induction chemotherapy.

6064 Background: Induction chemotherapy (IC) plus concurrent chemoradiotherapy has been recommended as the standard treatment for locoregionally advanced nasopharyngeal carcinoma(LA-NPC). However, concurrent chemotherapy was associated with increased toxicities, poor tolerance, and low completion rates. The aim of this study was to compare the efficacy and toxicity of IC+ radiotherapy (RT) and IC+ concurrent or adjuvant chemoradiotherapy (IC+CCRT/AC) in patients with negative post-IC EBV DNA. Methods: A total of 547 NPC patients with negative plasma EBV DNA post-IC were included. Patients were classified into the IC+RT group and the IC+ concurrent or adjuvant chemoradiotherapy (IC+CCRT/AC) group. Locoregional relapse-free survival (LRFS), distant metastasis-free survival (DMFS), overall survival (OS), and progression-free survival (PFS) were estimated and compared using the Kaplan-Meier method. Propensity-score matching (PSM) was performed to balance the variables. Results: The median follow-up time was 37 months. The 3-year LRFS, DMFS, OS, and PFS rates for the whole group were 92.2%, 92.4%, 96.4%, and 84.4%, respectively. There was no significant difference in LRFS, DMFS, OS, and PFS between the IC+RT and the IC+CCRT/AC group both before PSM (3-year rates of 91.1% vs. 92.6%, p = 0.94; 95.6% vs. 91.5%, p = 0.08; 95.2% vs. 96.8%, p = 0.80; 85.9% vs. 84.0%, p = 0.38) and after PSM (90.7% vs. 92.7%, p = 0.77; 96.8% vs. 93.7%, p = 0.29; 94.5% vs. 93.9%, p = 0.57; 84.7% vs. 85.6%, p = 0.96). Multivariate analysis demonstrated that treatment schedule was not an independent predictor for survival rates. Patients in the IC+RT group had fewer treatment-related acute toxicities and better tolerance. Conclusions: IC+RT displayed similar survival outcomes as IC+CCRT/AC for NPC patients with negative post-IC EBV DNA. Our current data seems not to support the routine use of concurrent or adjuvant chemotherapy after IC for unselected patients.

Neoadjuvant tislelizumab combined with chemoradiotherapy for resectable locally advanced esophageal squamous cell carcinoma (ESCC): Single arm phase II study.

4068 Background: This study aimed to evaluate the safety and efficacy of neoadjuvant tislelizumab combined with chemoradiotherapy in patients with resectable esophageal squamous cell cancer. Methods: This is a prospective single-arm clinical trial. A total of 20 patients with newly diagnosed resectable esophageal cancer (cT1-2N+ / cT3-4aN0-3 M0) received 2 cycles of tislelizumab (200mg every 3 weeks for 2 cycles) concurrent with chemoradiotherapy (radiotherapy: 41.4Gy in 23 fractions; chemotherapy: Paclitaxel (Albumin bound) 100mg/m2, and Cisplatin 75 mg/m2 once every 3 weeks for 2 cycles.) Radical esophagectomy was performed within 4-6 weeks after neoadjuvant therapy. PET/CT was performed at baseline and before surgery. Primary endpoints included pathological response rate (pCR) and major pathological response rate (MPR), the secondary endpoints were disease free survival and safety. Exploratory endpoints include molecular imaging research and immune biomarker to further explore the factors affecting the efficacy of neoadjuvant therapy for esophageal cancer. Results: Twenty patients enrolled, all of whom received neoadjuvant tislelizumab combined with chemoradiotherapy. Eighteen patients underwent radical esophagectomy. One patient underwent radical chemoradiotherapy due to lymph node metastases after neoadjuvant therapy. One patient died of pneumonia before surgery. Among 18 patients who underwent surgery, R0 was 100% (18/18), 9 patients achieved pCR (50.0%), and 13 patients achieved MPR (72.2%). Most of treatment-related adverse event (TRAE) were grade 1-2, and the most common TRAE was anemia (15, 75.0%). The grade 3 TRAE included 1 leukopenia (5.0%), 1 neutropenia (5.0%), 1 liver damage (5.0%), and 1 elevated cardiac troponin T (5.0%). A significant decrease in SUVmax was observed in both pCR and no-pCR patients after treatment. Baseline SUVmax in no-pCR patients tended to be higher than pCR patients(p=0.0642). Furthermore, a significant increase in circulating CD4+ T cells, CD4+ effector memory T cells (TEM), and M1 were found after treatment. Among the patients with pCR, the CD4+ TEM and cDCs after treatment were higher than those in the no-pCR patients, while Tregs and M2 were lower. Conclusions: Neoadjuvant tislelizumab combined with chemoradiotherapy for locally advanced ESCC has promising efficacy and good safety. Clinical trial information: NCT05323890 . [Table: see text]

Peripheral pre-existing cancer-antigen specific T-cell immunity as predictive biomarker for immunotherapy in NSCLC patients.

e20504 Background: Pre-existing Tumor Antigen specific T-cells describe the endogenous adaptive immunity before any treatment that may represent a valuable novel predictive biomarker for ICI treatment. We investigate the potential value of pre-existing cancer-antigen specific CD8+ T-cells as a circulating predictive biomarker. Additionally, we analyze the major differences of known immune-cell phenotypes between Pre-existing positive (PreI+) and Pre-existing negative immunity (PreI-) NSCLC patients. Here, we present the preliminary results of this study. Methods: Blood was collected from 24 patients with NSCLC, stage III PD-L1+, after completion of radical chemoradiation, before initiation of maintenance durvalumab. PBMCs were isolated with Ficoll density gradient centrifugation from patients and 10 healthy donors (HD). PreI was calculated by detecting endogenous IFNg expressing cells with FACS after in-vivo co-cultures of PBMCs with mixes of hTERT, MAGEA1, NY-ESO-1 και Survivin cancer-associated antigens. Immunophenotyping was performed by multi-color flow cytometry using antibodies against CD3, CD4, CD8, CD45RA, CD45RO, CCR7, PD-1, PD-L1 for T-cells. Results: From 24 patients receiving Durvalumab, 10/24 (41.6%) had peptide specific T-cells (PreI + patients), 60% (6/10) had detectable peptide specific T cells for all (4/4) antigens tested. Survival analysis revealed better PFS in PreI+ than PreI – patients (Log-rank = 0.06, median 333.5 and 185 days ) and better OS (p = 0.032, median not reached and 254 days). The levels of CD3CD4PD-1 were higher in patients compared to HD (p = 0.019) but there was not a difference between PreI+ and PreI- patients (p = 0.25). PreI+ patients had significantly higher numbers of CD3CD8PD-1 cells compared to PreI- (p = 0.024) but not CD3CD8PD-L1. Prei+ patients had high numbers of Teff (CD3+CD8+CD45RA+CD45RO-CCR7) compared to both HD (p = 0.0039) and PreI- (p = 0.032). Conclusions: Pre-existing tumor antigen specific immunity before initiation of ICI in NSCLC patients could serve as a good predictive factor of response. The study is ongoing.

Survival outcomes of neoadjuvant therapy followed by radical resection versus upfront surgery for stage I-III pancreatic ductal adenocarcinoma: a retrospective cohort study.

Neoadjuvant therapy remains controversial in treating resectable pancreatic ductal adenocarcinoma (PDAC) patients. This study aims to assess the impact of neoadjuvant therapy on survival in patients with PDAC according to their clinical stage. Patients with resected clinical Stage I-III PDAC from 2010 to 2019 were identified in the Surveillance, Epidemiology, and End Results database. A propensity score matching method was utilized within each stage to reduce potential selection bias between patients who underwent neoadjuvant chemotherapy followed by surgery and patients who underwent upfront surgery. An overall survival (OS) analysis was performed using the Kaplan-Meier method and a multivariate Cox proportional hazards model. A total of 13674 patients were included in the study. The majority of the patients (N=10715, 78.4%) underwent upfront surgery. Patients receiving neoadjuvant therapy followed by surgery had significantly longer OS than those with upfront surgery. Subgroup analysis revealed that the neoadjuvant chemoradiotherapy group's OS is comparable to neoadjuvant chemotherapy. In clinical Stage IA PDAC, there was no difference in survival between the neoadjuvant treatment and upfront surgery groups before or after matching. In Stage IB-III patients, neoadjuvant therapy followed by surgery improved OS before and after matching compared to upfront surgery. The results revealed the same OS benefits using the multivariate Cox proportional hazards model. Neoadjuvant therapy followed by surgery could improve OS over upfront surgery in Stage IB-III PDAC but did not provide a significant survival advantage in Stage IA PDAC.

Comment on "Neoadjuvant Chemotherapy With CAPOX Versus Chemoradiation for Locally Advanced Rectal Cancer With Uninvolved Mesorectal Fascia (CONVERT): Initial Results of a Phase III Trial" by Mei et al.: Two Overtreatments Compared.

Mei et al. published in Annals of Surgery1 the initial results of the CONVERT trial, comparing neoadjuvant chemotherapy with CAPOX versus standard chemoradiation for rectal cancer with uninvolved mesorectal fascia. The design of the study, reported results and conclusions raise concerns. It seems that a vast majority of the cohort did experience an overtreatment, as their tumors could be adequately treated with surgery alone.2,3 The authors do not discuss these limitations, nor have they reported, whether surgery alone was one of the options given to patients during the consent process. It is not clear, what was the benefit of neoadjuvant treatment in patients with primary operable tumors. The price of this treatment is mentioned. Despite relatively young (median age of 60 years, age limit 75 years) and healthy cohort (ECOG performance status ≤1, adequate hematologic, liver, and renal function), 70.3% in the neoadjuvant chemotherapy group and 64.7% in the neoadjuvant chemoradiotherapy group experienced toxicities. The postoperative morbidity was 18.8% and 25.7%, respectively. Nearly 10% in both groups did not receive surgery at all, and 13% refused postoperative therapy. The authors describe the downstaging of the tumors, but without admitting that the reliability of comparison between MRI and pathological findings is low.4–6 Post-treatment functional impairment, frequency, and severity of low anterior syndrome are also not reported. A statistical comparison of 2 overtreatments does not make the treatment appropriate. All treatment modalities in rectal cancer: surgery, radiotherapy, and chemotherapy do have a significant risk of complication. The combination of these treatment options could possibly potentiate their risks and adverse effects; therefore, selecting the therapy course is a difficult and careful process. The goal is to find a minimal therapy sufficient for success, not a maximal therapy applicable to the patient.

Treatment and prognosis analysis of 488 patients with FIGO 2018 stage Ⅲc squamous cervical cancer

Objective: To analyze the treatment and prognosis of patients with International Federation of Gynecology and Obstetrics (FIGO) 2018 stage Ⅲc cervical squamous cell carcinoma. Methods: A total of 488 patients at Zhejiang Cancer Hospital between May, 2013 to May, 2015 were enrolled. The clinical characteristics and prognosis were compared according to the treatment mode (surgery combined with postoperative chemoradiotherapy vs radical concurrent chemoradiotherapy). The median follow-up time was (96±12) months ( range time from 84 to 108 months). Results: (1) The data were divided into surgery combined with chemoradiotherapy group (surgery group) and concurrent chemoradiotherapy group (radiotherapy group), including 324 cases in the surgery group and 164 cases in the radiotherapy group. There were significant differences in Eastern Cooperation Oncology Group (ECOG) score, FIGO 2018 stage, large tumors (≥4 cm), total treatment time and total treatment cost between the two groups (all P<0.01). (2) Prognosis: ① for stage Ⅲc1 patients, there were 299 patients in the surgery group with 250 patients survived (83.6%). In the radiotherapy group, 74 patients survived (52.9%). The difference of survival rates between the two groups was statistically significant (P<0.001). For stage Ⅲc2 patients, there were 25 patients in surgery group with 12 patients survived (48.0%). In the radiotherapy group, there were 24 cases, 8 cases survived, the survival rate was 33.3%. There was no significant difference between the two groups (P=0.296). ② For patients with large tumors (≥4 cm) in the surgery group, there were 138 patients in the Ⅲc1 group with 112 patients survived (81.2%); in the radiotherapy group, there were 108 cases with 56 cases survived (51.9%). The difference between the two groups was statistically significant (P<0.001). Large tumors accounted for 46.2% (138/299) vs 77.1% (108/140) in the surgery group and radiotherapy group. The difference between the two groups was statistically significant (P<0.001). Further stratified analysis, a total of 46 patients with large tumors of FIGO 2009 stage Ⅱb in the radiotherapy group were extracted, and the survival rate was 67.4%, there was no significant difference compared with the surgery group (81.2%; P=0.052). ③ Of 126 patients with common iliac lymph node, 83 patients survived, with a survival rate of 65.9% (83/126). In the surgery group, 48 patients survived and 17 died, with a survival rate of 73.8%. In the radiotherapy group, 35 patients survived and 26 died, with a survival rate of 57.4%. There were no significant difference between the two groups (P=0.051). (3) Side effects: the incidence of lymphocysts and intestinal obstruction in the surgery group were higher than those in the radiotherapy group, and the incidence of ureteral obstruction and acute and chronic radiation enteritis were lower than those in the radiotherapy group, and there were statistically significant differences (all P<0.01). Conclusions: For stage Ⅲc1 patients who meet the conditions for surgery, surgery combined with postoperative adjuvant chemoradiotherapy and radical chemoradiotherapy are acceptable treatment methods regardless of pelvic lymph node metastasis (excluding common iliac lymph node metastasis), even if the maximum diameter of the tumor is ≥4 cm. For patients with common iliac lymph node metastasis and stage Ⅲc2, there is no significant difference in the survival rate between the two treatment methods. Based on the duration of treatment and economic considerations, concurrent chemoradiotherapy is recommended for the patients.

Comparison between radical surgery and chemoradiotherapy in patients with cervical esophageal cancer: a propensity score matched analysis

BackgroundThe prognostic value of radical surgery (RS) and chemoradiotherapy (CRT) for cervical esophageal cancer (CEC) was estimated using the Surveillance, Epidemiology and End Results (SEER) database after 1:1 propensity score matching (PSM).MethodsThis retrospective study used SEER data of CEC patients between 2004 and 2015. The prognostic effects on cancer-specific survival (CSS) were evaluated using multivariate cox regression analysis following radical surgery or CRT before and after PSM. The subgroup analysis of CSS is carried out according to T stages.ResultsA total of 440 patients met the eligibility criteria. Three hundred and fifty-six(80.9%)patients underwent chemoradiotherapy, and eighty-four (19.1%) patients underwent radical surgery. There were significant differences between patients of radical surgery and CRT groups with regard to the tumor grade, histology and N stage. After PSM, 80 matched pairs (A total of 160 patients) were selected. Multivariable cox regression analysis revealed no difference in the CSS of patients that underwent either radical surgery or CRT before [hazard ratio (HR): 0.955, 95% CI: 0.704–1.295, P = 0.766] and after PSM (HR: 0.767, 95% CI: 0.512–1.149, P = 0.198). Subgroup analysis revealed no significant difference in CSS between patients with radical surgery and CRT groups for all T stages (T 1–4, all P > 0.05).ConclusionsThis analysis revealed that the prognostic outcomes in patients with cervical esophageal cancer were comparable between radical surgery and CRT.

Treatment of FIGO 2018 stage IIIC cervical cancer with different local tumor factors

BackgroundTo compare the oncological outcomes of patients with FIGO 2018 stage IIIC cervical cancer (CC) involving different local tumor factors who underwent abdominal radical hysterectomy (ARH), neoadjuvant chemotherapy and radical surgery (NACT), or radical chemoradiotherapy (R-CT).MethodsBased on tumor staging, patients with stage IIIC were divided into T1, T2a, T2b, and T3 groups. Kaplan–Meier and Cox proportional hazards regression analysis were used to compare their overall survival (OS) and disease-free survival (DFS) of 5 years.ResultsWe included 4,086 patients (1,117, 1,019, 869, and 1,081 in the T1, T2a, T2b, and T3 groups, respectively). In the T1 group, NACT was correlated with a decrease in OS (hazard ratio [HR] = 1.631, 95% confidence interval [CI]: 1.150–2.315, P = 0.006) and DFS (HR = 1.665, 95% CI: 1.255–2.182, P < 0.001) than ARH. ARH and NACT were not correlated with OS (P = 0.226 and P = 0.921) or DFS (P = 0.343 and P = 0.535) than R-CT. In the T2a group, NACT was correlated with a decrease in OS (HR = 1.454, 95% CI: 1.057–2.000, P = 0.021) and DFS (HR = 1.529, 95% CI: 1.185–1.974, P = 0.001) than ARH. ARH and NACT were not correlated with OS (P = 0.736 and P = 0.267) or DFS (P = 0.714 and P = 0.087) than R-CT. In the T2b group, NACT was correlated with a decrease in DFS (HR = 1.847, 95% CI: 1.347–2.532, P < 0.001) than R-CT nevertheless was not correlated with OS (P = 0.146); ARH was not correlated with OS (P = 0.056) and DFS (P = 0.676). In the T3 group, the OS rates of ARH (n = 10), NACT (n = 18), and R-CT (n = 1053) were 67.5%, 53.1%, and 64.7% (P = 0.941), and the DFS rates were 68.6%, 45.5%, and 61.1%, respectively (P = 0.761).ConclusionR-CT oncological outcomes were not entirely superior to those of NACT or ARH under different local tumor factors with stage IIIC. NACT is not suitable for stage T1, T2a, and T2b. Nevertheless ARH is potentially applicable to stage T1, T2a, T2b and T3. The results of stage T3 require confirmation through further research due to disparity in case numbers in each subgroup.

PO-1396 Long-term outcomes for locally advanced anal cancer after radical chemoradiotherapy

PO-1396 Long-term outcomes for locally advanced anal cancer after radical chemoradiotherapy

Metronomic adjuvant chemotherapy evaluation in locallyadvanced head and neck cancers post radical chemoradiation - a randomised trial.

Locally advanced head and neck cancers treated with radical chemoradiation have unsatisfactory outcomes. Oral metronomic chemotherapy improves outcomes in comparison to maximum tolerated dose chemotherapy in the palliative setting. Limited evidence suggests that it may do so in an adjuvant setting. Hence this randomized study was conducted. Patients of head and neck (HN) cancer with primary in oropharynx, larynx or hypopharynx, with PS 0-2 post radical chemoradiation with documented complete response were randomized 1:1 to either observation or oral metronomic adjuvant chemotherapy (MAC) for 18 months. MAC consisted of weekly oral methotrexate (15mg/m2) and celecoxib (200mg PO BD). The primary endpoint was OS and the overall sample size was 1038. The study had 3 planned interim analyses for efficacy and futility. Trial registration- Clinical Trials Registry- India (CTRI): CTRI/2016/09/007315 [Registered on: 28/09/2016] Trial Registered Prospectively. 137 patients were recruited and an interim analysis was done. The 3 year PFS was 68.7% (95% CI 55.1-79.0) versus 60.8% (95% CI 47.9-71.4) in the observation and metronomic arm respectively (P value=0.230). The hazard ratio was 1.42 (95% CI 0.80-2.51; P value=0.231). The 3 year OS was 79.4% (95% CI 66.3-87.9) versus 62.4% (95% CI 49.5-72.8) in the observation and metronomic arm respectively (P value=0.047). The hazard ratio was 1.83 (95% CI 1.0-3.36; P value=0.051). In this phase 3 randomized study, oral metronomic combinations of weekly methotrexate and daily celecoxib failed to improve the PFS or OS. Hence observation post-complete response post radical chemoradiation remains the standard of care. ICON funded this study.

Radical chemoradiotherapy to the bladder: review of practice at the Northern Centre for Cancer Care

radical chemoradiotherapy to the bladder: review of practice at the Northern Centre for Cancer Care

PD-0398 Clinical outcomes of Thyroid Sparing Radical Chemoradiation in the treatment of Head and Neck cancer

PD-0398 Clinical outcomes of Thyroid Sparing Radical Chemoradiation in the treatment of Head and Neck cancer

Isotoxic dose escalated radiotherapy for glioblastoma based on diffusion-weighted MRI and tumor control probability-an in-silico study.

Glioblastoma (GBM) is the most common malignant primary brain tumor with local recurrence after radiotherapy (RT), the most common mode of failure. Standard RT practice applies the prescription dose uniformly across tumor volume disregarding radiological tumor heterogeneity. We present a novel strategy using diffusion-weighted (DW-) MRI to calculate the cellular density within the gross tumor volume (GTV) in order to facilitate dose escalation to a biological target volume (BTV) to improve tumor control probability (TCP). The pre-treatment apparent diffusion coefficient (ADC) maps derived from DW-MRI of ten GBM patients treated with radical chemoradiotherapy were used to calculate the local cellular density based on published data. Then, a TCP model was used to calculate TCP maps from the derived cell density values. The dose was escalated using a simultaneous integrated boost (SIB) to the BTV, defined as the voxels for which the expected pre-boost TCP was in the lowest quartile of the TCP range for each patient. The SIB dose was chosen so that the TCP in the BTV increased to match the average TCP of the whole tumor. By applying a SIB of between 3.60 Gy and 16.80 Gy isotoxically to the BTV, the cohort's calculated TCP increased by a mean of 8.44% (ranging from 7.19 to 16.84%). The radiation dose to organ at risk is still under their tolerance. Our findings indicate that TCPs of GBM patients could be increased by escalating radiation doses to intratumoral locations guided by the patient's biology (i.e., cellularity), moreover offering the possibility for personalized RT GBM treatments. A personalized and voxel level SIB radiotherapy method for GBM is proposed using DW-MRI, which can increase the tumor control probability and maintain organ at risk dose constraints.

Dosimetric comparison of 3DCRT and IMRT in radical chemoradiotherapy of squamous cell carcinoma esophagus.

Radical chemoradiation is the standard of treatment for locally advanced squamous cell carcinoma of esophagus and for patients with operable disease, but who are medically unfit or unwilling for surgery. As the esophagus is a central organ, the planning target volume (PTV) is central, lies close to the spinal cord and heart, and is surrounded by the lung, which is a radiosensitive organ. Irradiation of these critical structures is reduced by the use of three-dimensional conformal radiation therapy (3DCRT). Intensity-modulated radiation therapy (IMRT) has the potential to improve the uniformity of dose distribution to the tumor and reduce the dose received by surrounding normal tissues. 1. To compare the dose distribution, conformity, and homogeneity indices in radical radiotherapy of squamous cell carcinoma of esophagus using 3DCRT and IMRT techniques 2. To compare the doses received by critical structures such as heart, lung, spinal cord, and liver. All cases of squamous cell carcinoma esophagus treated with radical chemoradiation to a dose of 50 Gy in 25 fractions using 3DCRT technique from January 2018 to July 2019 were included. IMRT plans were generated for these cases.The parameters that represent dose distribution to the target volume and the dose received by the organs at risk were obtained from the dose-volume histogram. The difference in the mean values of the parameters between the two techniques was calculated. The statistical significance of the difference was determined using Student's t-test and Wilcoxon signed-rank test. The volume of PTV receiving 105% and 107% of prescribed dose was significantly lower with IMRT (3.540% and 0.008%, respectively) compared to 3DCRT (7.654% and 0.623%). The homogeneity index was better with IMRT (0.088 vs. 0.107) than 3DCRT. Conformity index was found to be better with IMRT (1.149 vs. 1.573). Mean heart dose (18.216 vs. 24.591 Gy) and the volume of heart receiving 30 Gy were reduced with IMRT. The volume of lung receiving 20 Gy and the volume receiving 5 Gy were not significantly different between 3DCRT and IMRT. Maximum dose to spinal cord was similar with 3DCRT and IMRT. IMRT avoids areas of excessive irradiation within the PTV. IMRT improves dose conformity to the target volume and homogeneity of dose distribution within the PTV. The cardiac dose is significantly reduced with IMRT. The mean lung dose remains similar to 3DCRT. There is no significant increase in the volume of lung receiving low-dose radiation with IMRT.

Adding Induction Chemotherapy Before Chemoradiotherapy with Total Mesorectal Excision and Selective Lateral Lymph Node Dissection for Patients with Poor-Risk, Locally Advanced, Mid-to-Low Rectal Cancer May Improve Oncologic Outcomes: A Propensity Score-Matched Analysis.

This study aimed to investigate whether the addition of induction chemotherapy before chemoradiotherapy (CRT) and total mesorectal excision (TME) with selective lateral lymph node dissection improves disease-free survival for patients with poor-risk, mid-to-low rectal cancer. The authors' institutional prospective database was queried for consecutive patients with clinical stage II or III, primary, poor-risk, mid-to-low rectal cancer who received neoadjuvant treatment followed by TME from 2004 to 2019. The outcomes for the patients who received induction chemotherapy before neoadjuvant CRT (induction-CRT group) were compared (via log-rank tests) with those for a propensity score-matched cohort of patients who received neoadjuvant CRT without induction chemotherapy (CRT group). From 715 eligible patients, the study selected two matched cohorts with 130 patients each. The median follow-up duration was 5.4 years for the CRT group and 4.1 years for the induction-CRT group. The induction-CRT group had significantly higher rates of 3-year disease-free survival (83.5 % vs 71.4 %; p = 0.015), distant metastasis-free survival (84.3 % vs 75.2 %; p = 0.049), and local recurrence-free survival (98.4 % vs 94.4 %; p = 0.048) than the CRT group. The pathologically complete response rate also was higher in the induction-CRT group than in the CRT group (26.2 % vs 10.0 %; p < 0.001). Postoperative major complications (Clavien-Dindo classification ≥III) did not differ significantly between the two groups (12.3 % vs 10.8 %; p = 0.698). The addition of induction chemotherapy to neoadjuvant CRT appeared to improve oncologic outcomes significantly, including disease-free survival, for the patients with poor-risk, mid-to-low rectal cancer who underwent TME using selective lateral lymph node dissection.

The impact of neoadjuvant immunotherapy on perioperative outcomes and survival after esophagectomy for esophageal cancer

ObjectiveImmunotherapy for esophageal cancer is relatively novel but increasingly used. This study evaluated the early use of immunotherapy as an adjunct to neoadjuvant chemoradiotherapy before esophagectomy for locally advanced disease. MethodsPerioperative morbidity (composite of mortality, hospitalization ≥21 days, or readmission) and survival of patients with locally advanced (cT3N0M0, cT1-3N + M0) distal esophageal cancer in the National Cancer Database from 2013 to 2020 who underwent neoadjuvant immunotherapy plus chemoradiotherapy or chemoradiotherapy alone followed by esophagectomy were evaluated using logistic regression, Kaplan–Meier curves, Cox proportional hazards methods, and propensity-matched analysis. ResultsImmunotherapy was used in 165 (1.6%) of 10,348 patients. Younger age (odds ratio, 0.66; 95% confidence interval, 0.53-0.81; P < .001) predicted immunotherapy use, which slightly delayed time from diagnosis to surgery versus chemoradiation alone (immunotherapy 148 [interquartile range, 128-177] days vs chemoradiation 138 [interquartile range, 120-162] days, P < .001). There were no statistically significant differences between the immunotherapy and chemoradiation groups for the composite major morbidity index (14.5% [24/165] vs 15.6% [1584/10,183], P = .8). Immunotherapy was associated with a significant improvement in median overall survival (69.1 months vs 56.3 months, P = .005) and 3-year overall survival in univariate analysis (65.6% [95% confidence interval, 57.7-74.5] vs 55.0% [53.9-56.1], P = .005), and independently predicted improved survival in multivariable analysis (hazard ratio 0.68 [95% confidence interval, 0.52-0.89], P = .006). Propensity-matched analysis also showed that immunotherapy use was not associated with increased surgical morbidity (P = .5) but was associated with improved survival (P = .047). ConclusionsNeoadjuvant immunotherapy use before esophagectomy for locally advanced esophageal cancer did not lead to worse perioperative outcomes and shows promising results on midterm survival.

Intramuscular injections of human placental extract versus conventional symptomatic approaches in radiation-induced oral mucositis, in patients with head and neck cancers, on definitive chemoradiotherapy - A ray of hope?

Despite the availability of a wide range of agents, no single treatment exists for the management of radiation-induced oral mucositis, in patients, with head and neck malignancies, on radical chemoradiation; a debilitating and limiting sequela. Human placental extract is one option that has been proposed. This study aimed at evaluating the therapeutic benefits of human placental extract (Placentrex) in the management of radiation-induced oral mucositis in patients on curative intent treatment for head and neck cancers with concurrent chemoradiation, and to compare the observations with other conventional approaches. Patients presenting to the Department of Radiation Oncology, of a tertiary cancer care center, with biopsy-proven carcinoma of the oral cavity, oropharynx, and hypopharynx, planned for definitive, curative intent chemoradiation, between January 2020 and June 2021, were recruited for this study. The interventional group received a deep intramuscular injection of 2 ml of Placentrex to the deltoid muscle, once-a-day from the 11th fraction of radiation till completion, on treatment and non-treatment days. The control group received supportive, symptomatic, conventional treatments for mucositis. The response was assessed every week during treatment and at the third and sixth months of follow-up and was compared. The study comprised 26 patients, 15 in the interventional group and 11 in the control group. On completion of treatment, 40% in the interventional arm and 81.82% in the control arm had progressed to grade 2 and 3 mucositis (P < 0.05). Treatment interruption was seen in 13% in the interventional arm and 55% in the control arm (P < 0.001). Results from this study show that human placental extract, injection Placentrex, had a significant effect in decreasing the severity of radiation-induced mucositis and thereby reducing any interruption or delay in treatment when compared to other conventional methods.

63 - Implementing adjuvant immunotherapy following radical chemoradiotherapy for stage III non-small cell lung cancer in UK clinical practice: are the PACIFIC trial outcomes achievable in the real world?

63 - Implementing adjuvant immunotherapy following radical chemoradiotherapy for stage III non-small cell lung cancer in UK clinical practice: are the PACIFIC trial outcomes achievable in the real world?

143 - Radical chemoradiation for stage III NSCLC patients with N3 disease: futile exercise or a fruitful venture?

143 - Radical chemoradiation for stage III NSCLC patients with N3 disease: futile exercise or a fruitful venture?