Curative Chemoradiotherapy Research Articles

Development of brain metastases in patients managed with non-curative thoracic radiotherapy for stage II/III non-small cell lung cancer

BackgroundThis retrospective study analyzed the incidence of subsequent brain metastases after palliative radiotherapy or chemoradiation in patients with stage II/III non-small cell lung cancer (NSCLC). Risk factors for brain metastases development and survival after diagnosis were evaluated.MethodsDifferent baseline parameters including but not limited to age, stage and target volume size were assessed. Outcomes were abstracted from electronic health records. Uni- and multivariate tests were performed.ResultsThe study included 102 patients and found an actuarial risk of brain metastases of 15% (standard error ± 4) at one year and 20% (± 5) at two years. The maximum time interval was 15 months from start of radiation treatment. A non-significant survival difference was observed (median 12 months without versus 8.3 months with brain metastases, p = 0.21). Incidence was higher in patients with N2/3 stage, larger planning target volume size, and younger age (univariately significant factors). Trends were seen for stage III and adenocarcinoma histology. The multivariate analysis confirmed age as the most important risk factor.ConclusionThe risk of brain metastases development was comparable to that reported in studies of curative chemoradiation. All events occurred within 15 months of follow-up, suggesting that long-term surveillance imaging may not be warranted. Patients younger than 60 years had a very high risk of brain metastases development.

Role of dynamic ctDNA monitoring in cervical and anal epidermoid carcinomas under curative chemoradiation.

3141 Background: Cervical and anal canal squamous cell carcinoma (SSC) are a significant health problem in underdevelopment countries. Definitive chemoradiation (CRT) is the standard-of-care (SOC) approach for curative treatment in locally advanced disease. Due to the common substantial local inflammation during CRT, the conventional clinical image cannot identify non-responders early. In this scenario, the evaluation of circulating tumor DNA (ctDNA) is a promising tool for real-time tumor response monitoring. Methods: We performed a prospective multicentric cohort study of patients treated between 2020 and 2023 in tertiary oncologic centers in Brazil to evaluate the role of ctDNA dynamic monitoring in epidermoid cervical (CC) and anal cancer (AC) T1-4, N0-1, M0 by AJCC 8th edition and candidates to complete curative CRT. The cDNA was assessed by Signatera test at D1, D29, immediately post-treatment, 8 weeks (w) post-CRT, 24w post-CRT, every 6 months (m) in the first 1-2 years(y), and yearly at 3-5y of follow-up (FUP). The primary endpoint was to estimate the correlation of ctDNA with a tumoral response assessed by conventional routine image and clinical evaluation at 8w. Secondary endpoints included a correlation between ctDNA results at different time points with progression-free survival (PFS) and overall survival (OS). The predictive potential of the biomarker was evaluated using receiving operating characteristic (ROC) curve analysis. Results: We included 33 patients, and 27 were evaluable with ctDNA, with a median FUP of 10m. The majority were female (n=23, 85.1%), and 3 (11%) were HIV-positive(+). Most patients presented with positive nodes and stage III disease (n=18, 66.6%). In the AC group (n=15), the majority received CRT with capecitabine and cisplatin (n=12, 55.5%); in the CC group (n=12), all pts received cisplatin. All pts tested expressed ctDNA+ before treatment. At 8w, images had a sensitivity of 42.8% and specificity of 100% for disease progression (area under the curve [AUC] 0.714), while ctDNA yielded a sensitivity of 85.7% and specificity of 89.4% (AUC 0.875). The ctDNA+ immediately after CRT ended (32%) was consistent with ctDNA+ at 8w (30.7%) and 24w (30%). Pts with ctDNA+ immediately post CRT have a higher risk of disease progression with PFS of 8.2m in ctDNA+ and not reached in ctDNA- group (HR:17.5; IC95%:1.9-157.3; p=0.01). Data are immature for OS analysis. Conclusions: CtDNA immediately post-CRT has a high predictive value in patients with anal and cervical tumors in early access CRT non-responders, who are at a high risk of disease progression. This biomarker should be considered for tailoring strategies of treatment escalation in this population.

A first-in-human, phase 1/2 trial of FOG-001, a β-catenin:TCF antagonist, in patients with locally advanced or metastatic solid tumors.

TPS3175 Background: The Wnt/β-catenin pathway is a frequently activated oncogenic pathway and a well-described driver of many cancers. FOG-001 is designed to be a first-in-class direct inhibitor of β-catenin that blocks β-catenin’s interaction with the T-cell factor (TCF) family of transcription factors. Preclinical studies have indicated FOG-001 can cause tumor growth inhibition and regression by disrupting β-catenin-dependent signaling. FOG-001 is unique from previously reported Wnt/β-catenin pathway modulators as it is designed to directly inhibit TCF transcription factor and β-catenin interaction, the most downstream node in the Wnt pathway. It is hypothesized FOG-001 will abrogate the hyperactivation of the Wnt pathway that is driven by most known pathway mutations. Methods: This first-in-human, Phase 1/2, multicenter, open-label, dose escalation (Parts 1a and 1b) and dose-expansion (Part 2) study is evaluating the safety/tolerability, pharmacokinetics (PK), pharmacodynamics (PD), and antitumor activity of FOG-001 in patients with advanced or metastatic solid tumors. Patients with the following tumor types are eligible: microsatellite stable (MSS) colorectal cancer (CRC) or any solid tumor with documented Wnt pathway activating mutation (WPAM) (Part 1a), MSS CRC only (Part 1b) and MSS CRC, gastric/gastroesophageal (GEJ) cancer, non-small cell lung cancer (NSCLC), and any solid tumors with documented WPAM in Part 2. Patients must have received ≥1 prior systemic anticancer therapy(ies) and be ineligible for curative surgery or curative chemoradiation. In Part 1, FOG-001 is administered at escalating doses via intravenous (IV) infusion on Days 1, 8, 15, and 22 of each 4-week cycle; additional dosing regimens may be explored. After selection of the preliminary recommended Phase 2 dose(s) (pRP2D) and regimen(s) in Part 1, the following cohorts will be enrolled to receive FOG-001 at the pRP2D in Part 2: (2a) MSS CRC; (2b) NSCLC with documented WPAM in adenomatous polyposis coli (APC) or β-catenin; (2c) gastric/GEJ cancer with documented WPAM in APC or β-catenin; and (2d) solid tumors with ≥1 documented WPAM in any predefined Wnt pathway genes. The primary endpoints are safety/tolerability (Parts 1 and 2), and also preliminary antitumor activity (objective response rate) (Part 2). Secondary endpoints are PK, PD, and additional antitumor activity assessments. Enrollment in Part 1 is ongoing. Clinical trial information: NCT05919264 .

Cisplatin and capecitabine as definitive chemoradiation for squamous cell carcinoma of the anal canal (SCCAC): A prospective cohort.

e15503 Background: SCCAC is a rare disease. The standard of care treatment with curative intent is chemoradiation (CRT) with mitomycin (MMC) or cisplatin (CDDP) plus infusional 5-Fluoracil (5-FU). Capecitabine may replace 5-FU in MMC doublet. However, MMC and infusional pumps are frequently unavailable in underdeveloped countries. CCDP and capecitabine are widely available, but there is no prospective data about the feasibility and efficacy of this combination in a definitive SCCAC CRT setting. Methods: A Prospective cohort study aimed to evaluate the safety and efficacy of treatment with chemoradiation with CDDP 60mg/m2 D1 and D29 plus Capecitabine 825mg/m2 BID in a population without MMC and infusional pump access. Eligible patients (pts) had T2-4, N0-3, and M0 disease candidates for a full curative CRT regimen. The study data were prospectively collected using REDCap. The primary endpoint was the response by RECIST v.1.1 at 24 weeks(w). The secondary endpoints included toxicity by CTCAE v.5.0, adherence, PFS, and OS. Results: We enrolled 40 consecutive pts between Aug/2019-Dec/2022 in a tertiary cancer center in Brazil. The median age was 61y, the majority were stage III (n = 31, 77.5%) and ECOG 1 (n = 20, 50%). HIV+ serology was observed in 11 pts (27,5%). All patients received CRT, with a median dose of 54Gy in the primary tumor and 45Gy in the elective nodes. At 8w, 35% (n = 14) had a complete response (CR), 50% (n = 20) partial response (PR), and 2.5% (n = 1) progressive disease (PD). At 6 months, CR was observed in 55% (n = 22), PR in 22.5% (n = 9), and PD in 10% (n = 4). 11 pts had disease recurrence, and six died. 1y OS was 94.7% (IC95%: 80.7- 98.6%), and 1y PFS was 75.3% (IC95%:57.8 - 86.3%). Colostomy-free survival at one year was 89.6% (IC95%: 74.7 - 95.9%). Median PFS and OS were not reached with a 2-year median follow-up. Regarding toxicities, radiodermatitis was observed in 94% (n = 36), nausea in 90% (n = 36), and diarrhea in 65% (n = 26). Any grade 3/4 toxicity was present in 27.5% (n = 11), being the majority of radiodermatitis. Four older pts (average age 73y) had definitive suspension of treatment due to toxicity, 06 pts were hospitalized because of a skin infection, and one died due to treatment toxicity. Conclusions: Definitive chemoradiotherapy with cisplatin and capecitabine is feasible; however, older populations require extra attention to early toxicities management.

Significance of HIV status in cervical cancer patients receiving curative chemoradiation therapy, definitive radiation alone, or palliative radiation in Botswana.

Cervical cancer associated with human papillomavirus has the highest cancer incidence and mortality for women in Botswana because of a high HIV prevalence and limited screening. This study investigates the significance of HIV on the overall survival (OS) of patients with locally advanced cervical cancer by various treatment categories (curative chemoradiation, definitive radiation [RT] alone, or palliative RT alone). This study included patients diagnosed with cervical cancer between 2013 and 2020, prospectively enrolled in the Botswana Prospective Cancer Cohort. OS based on HIV status and completion of planned treatment regimen was estimated by the Kaplan-Meier method. Comparisons of 2-year OS by HIV status was performed by the log-rank test, univariate and multivariable Cox analyses adjusting for cancer stage, RT dose, number of chemotherapy cycles, and baseline hemoglobin levels. Of 1131 patients diagnosed with stage IB-IVB cervical cancer, 69.8% were women living with HIV (n=789). For patients receiving curative chemoradiation, HIV status was not significantly associated with OS in unadjusted (p=.987) and adjusted (p=.578) analyses. For RT only treatment and definitive (high-dose) RT alone, HIV status was significantly associated with OS in unadjusted analysis (HR=1.77, p=.002; HR=1.95, p=.014), but not in adjusted analysis (p=.227, p=.73). For patients receiving palliative (low-dose) RT, HIV status was not associated with OS in unadjusted (p=.835) or adjusted analysis (p=.359). In Botswana, a resource-limited setting, HIV status had no significant effect on 2-year OS in patients with cervical cancer with well-managed HIV receiving chemoradiation, RT alone, or palliative RT. This demonstrates that patients living with HIV receiving antiretroviral treatment can receive clinically appropriate treatment with no evidence that HIV may lead to poorer outcomes.

Liquid biopsy for breast cancer and other solid tumors: a review of recent advances.

Liquid biopsy using circulating tumor DNA (ctDNA) has been reported to be less invasive and effective for comprehensive genetic analysis of heterogeneous solid tumors, including decision-making for therapeutic strategies, predicting recurrence, and detecting genetic factors related to treatment resistance in various types of cancers. Breast cancer, colorectal cancer, and lung cancer are among the most prevalent malignancies worldwide, and clinical studies of liquid biopsy for these cancers are ongoing. Liquid biopsy has been used as a companion diagnostic tool in clinical settings, and research findings have accumulated, especially in cases of colorectal cancer after curative resection and non-small cell lung cancer (NSCLC) after curative chemoradiotherapy, in which ctDNA detection helps predict eligibility for adjuvant chemotherapy. Liquid biopsy using ctDNA shows promise across a wide range of cancer types, including breast cancer, and its clinical applications are expected to expand further through ongoing research. In this article, studies on liquid biopsy in breast cancer, colorectal cancer, and NSCLC are compared focusing on ctDNA.

235 Nasopharyngeal cancer chemotherapy – before or after curative chemoradiation?

235 Nasopharyngeal cancer chemotherapy – before or after curative chemoradiation?

Comparing deep learning and handcrafted radiomics to predict chemoradiotherapy response for locally advanced cervical cancer using pretreatment MRI

Concurrent chemoradiotherapy (CRT) is the standard treatment for locally advanced cervical cancer (LACC), but its responsiveness varies among patients. A reliable tool for predicting CRT responses is necessary for personalized cancer treatment. In this study, we constructed prediction models using handcrafted radiomics (HCR) and deep learning radiomics (DLR) based on pretreatment MRI data to predict CRT response in LACC. Furthermore, we investigated the potential improvement in prediction performance by incorporating clinical factors. A total of 252 LACC patients undergoing curative chemoradiotherapy are included. The patients are randomly divided into two independent groups for the training (167 patients) and test datasets (85 patients). Contrast-enhanced T1- and T2-weighted MR scans are obtained. For HCR analysis, 1890 imaging features are extracted and a support vector machine classifier with a five-fold cross-validation is trained on training dataset to predict CRT response and subsequently validated on test dataset. For DLR analysis, a 3-dimensional convolutional neural network was trained on training dataset and validated on test dataset. In conclusion, both HCR and DLR models could predict CRT responses in patients with LACC. The integration of clinical factors into radiomics prediction models tended to improve performance in HCR analysis. Our findings may contribute to the development of personalized treatment strategies for LACC patients.

Circulating tumour HPV16 DNA quantification – A prognostic tool for progression-free survival in patients with HPV-related oropharyngeal carcinoma receiving curative chemoradiotherapy

Background and PurposeCirculating tumour (ct) human papillomavirus (HPV) DNA is detectable in HPV-related oropharyngeal carcinoma (OPSCC) patients and has the potential to become an important clinical tool. This study aimed to evaluate the prognostic significance of ctHPV16-DNA kinetics during treatment with chemoradiotherapy in HPV-related OPSCC. Patients with p16-positive OPSCC recruited to the ARTSCAN III trial, comparing radiotherapy plus cisplatin with radiotherapy plus cetuximab, constituted the study cohort. Materials and methodsBlood samples before start and at the end of treatment of 136 patients were analysed. ctHPV16-DNA was quantified by real-time (q)PCR. The correlation between ctHPV16-DNA levels and tumour burden was investigated with Pearson regression analysis. The prognostic value of ctHPV16-DNA levels at baseline and decline during treatment was evaluated by area-under-the-curve (AUC) calculations and analysed with univariable and multivariable Cox proportional hazards models. ResultsctHPV16-DNA was detectable with qPCR in 108/136 patients before start of treatment and cleared in 74% of these patients at the end of treatment. Disease burden was significantly correlated with baseline ctHPV16-DNA levels (R = 0.39, p=<0.001). Both lower baseline levels and AUC-ctHPV16DNA were associated with improved progression-free survival (p = 0.01 and p < 0.001), overall survival (p = 0.013 and p = 0.002), but not local tumour control (p = 0.12 and p = 0.2, respectively), with a stronger association for AUC-ctHPV16DNA (likelihood ratio test 10.5 vs 6.5 in Cox regression analyses of progression-free survival). In multivariable analysis including tumour volume (GTV-T) and treatment allocation (cisplatin vs cetuximab), AUC-ctHPV16DNA remained a significant prognostic marker of progression-free survival. ConclusionctHPV16-DNA is an independent prognostic factor in HPV-related OPSCC.

Lymphatic mapping for image-guided radiotherapy in patients with locally advanced uterine cervical cancer: a feasibility study

BackgroundLymph node metastasis is an important prognostic factor in locally advanced cervical cancer (LACC). No imaging method can successfully detect all (micro)metastases. This may result in (lymph node) recurrence after chemoradiation. We hypothesized that lymphatic mapping could identify nodes at risk and if radiation treatment volumes are adapted based on the lymphatic map, (micro)metastases not shown on imaging could be treated. We investigated the feasibility of lymphatic mapping to image lymph nodes at risk for (micro)metastases in LACC and assessed the radiotherapy dose on the nodes at risk.MethodsPatients with LACC were included between July 2020 and July 2022. Inclusion criteria were: ≥ 18 years old, intended curative chemoradiotherapy, investigation under anesthesia. Exclusion criteria were: pregnancy and extreme obesity. All patients underwent abdominal MRI, [18F]FDG-PET/CT and lymphatic mapping after administration of 6–8 depots of 99mTc]Tc-nanocolloid followed by planar and SPECT/CT images 2–4 and 24 h post-injection.ResultsSeventeen patients participated. In total, 40 nodes at risk were visualized on the lymphatic map in 13/17 patients with a median of two [range 0–7, IQR 0.5–3] nodes per patient, with unilateral drainage in 4/13 and bilateral drainage in 9/13 patients. No complications occurred. The lymphatic map showed more nodes compared to suspicious nodes on MRI or [18F]FDG-PET/CT in 8/14 patients. Sixteen patients were treated with radiotherapy with 34 visualized nodes on the lymphatic map. Of these nodes, 20/34 (58.8%) received suboptimal radiotherapy: 7/34 nodes did not receive radiotherapy at all, and 13/34 received external beam radiotherapy (EBRT), but no simultaneous integrated boost (SIB).ConclusionLymphatic mapping is feasible in LACC. Almost 60% of nodes at risk received suboptimal treatment during chemoradiation. As treatment failure could be caused by (micro)metastasis in some of these nodes, including nodes at risk in the radiotherapy treatment volume could improve radiotherapy treatment outcome in LACC.Trail registration The study was first registered at the International Clinical Trial Registry Platform (ICTRP) under number of NL9323 on 4 March 2021. Considering the source platform was not operational anymore, the study was retrospectively registered again on February 27, 2023 at CilicalTrials.gov under number of NCT05746156.

Prognostic factors of long-term outcomes after primary chemo-radiotherapy in non-metastatic anal squamous cell carcinoma: An international bicentric cohort.

e15501 Background: Anal squamous cell carcinoma (ASCC) is a rare malignancy with a rising incidence associated with Human papillomavirus (HPV) infection. Locally-advanced disease is associated with a 30% rate of treatment failure after standard chemoradiotherapy (CRT). We aimed to elucidate prognostic factors for ASCC after curative CRT. Methods: A retrospective multicenter study of 176 consecutive patients with ASCC having completed CRT treated between 2010 and 2017 at 2 centers. Complete response (CR), disease-free survival (DFS) and overall survival (OS) were analyzed by Kaplan–Meier estimates with log-rank tests. The hierarchical clustering on principal components (HCPC) method was employed in an unsupervised and multivariate approach. Results: CR rate was 68% and was predictive of DFS (p &lt; 0.0001) and OS (p &lt; 0.0001), where non-CR cases were associated shorter DFS (HR = 16.5, 95% CI 8.19-33.21) and OS (HR = 8.42, 95% CI 3.77–18.81) in univariate analysis. Median follow-up was 38 months, with 3-year DFS of 71%. Prognostic factors for DFS were cT1-T2 (p = 0.0001), N0 (p = 0.03), HIV-positive (p = 0.04), HIV-HPV coinfection (p = 0.02), and well-differentiated tumors (p = 0.03). Three-year OS was 81.6%. Female sex (p = 0.05), cT1-T2 (p = 0.019), and well-differentiated tumors (p = 0.003) were associated with better OS. This unsupervised analysis demonstrates clear segregation, identifying that poor prognosis clusters associated with shorter DFS (HR = 1.66, 95% CI = 1.21–2.27, p = 0.0012) were enriched with locally-advanced disease, anal canal location, HPV-HIV coinfection, and non-CR. Conclusions: In conclusion, our results reinforce the prognostic value of T stage, N stage, sex, differentiation status, tumor location, and HIV-HPV coinfection in ASCC after CRT.

Prognostic Factors of Long-Term Outcomes after Primary Chemo-Radiotherapy in Non-Metastatic Anal Squamous Cell Carcinoma: An International Bicentric Cohort.

Anal squamous cell carcinoma (ASCC) is a rare malignancy with a rising incidence associated with human papillomavirus (HPV) infection. The locally advanced disease is associated with a 30% rate of treatment failure after standard chemoradiotherapy (CRT). We aimed to elucidate the prognostic factors for ASCC after curative CRT. A retrospective multicenter study of 176 consecutive patients with ASCC having completed CRT treated between 2010 and 2017 at two centers was performed. Complete response (CR), disease-free survival (DFS), and overall survival (OS) were analyzed by Kaplan-Meier estimates with log-rank tests. The hierarchical clustering on principal components (HCPC) method was employed in an unsupervised and multivariate approach. The CR rate was 70% and was predictive of DFS (p < 0.0001) and OS (p < 0.0001), where non-CR cases were associated with shorter DFS (HR = 16.5, 95% CI 8.19-33.21) and OS (HR = 8.42, 95% CI 3.77-18.81) in a univariate analysis. The median follow-up was 38 months, with a 3-year DFS of 71%. The prognostic factors for DFS were cT1-T2 (p = 0.0002), N0 (p = 0.035), HIV-positive (p = 0.047), HIV-HPV coinfection (p = 0.018), and well-differentiated tumors (p = 0.037). The three-year OS was 81.6%. Female sex (p = 0.05), cT1-T2 (p = 0.02) and well-differentiated tumors (p = 0.003) were associated with better OS. The unsupervised analysis demonstrated a clear segregation of patients in three clusters, identifying that poor prognosis clusters associated with shorter DFS (HR = 1.74 95% CI = 1.25-2.42, p = 0.0008) were enriched with the locally advanced disease, anal canal location, HIV-HPV coinfection, and non-CR. In conclusion, our results reinforce the prognostic value of T stage, N stage, sex, differentiation status, tumor location, and HIV-HPV coinfection in ASCC after CRT.

Chemoradiation for muscle-invasive bladder cancer using 5-fluorouracil versus capecitabine: A nationwide cohort study

Background and purposeOral capecitabine and intravenous 5-fluorouracil (5-FU) are both used as a radiosensitizer in chemoradiotherapy (CRT). A capecitabine-based regimen is more convenient for both patients and healthcare professionals. Since large comparative studies are lacking, we compared toxicity, overall survival (OS) and disease-free survival (DFS) between both CRT-regimens in patients with muscle-invasive bladder cancer (MIBC). Materials and methodsAll patients diagnosed with non-metastatic MIBC between November 2017-November 2019 were consecutively included in the BlaZIB study. Data on patient, tumor, treatment characteristics and toxicity were prospectively collected from the medical files. From this cohort, all patients with cT2-4aN0-2/xM0/x, treated with capecitabine or 5-FU-based CRT were included in the current study. Toxicity in both groups was compared using Fisher-exact tests. Propensity score-based inverse probability treatment weighting (IPTW) was applied to correct for baseline differences between groups. IPTW-adjusted Kaplan-Meier OS and DFS curves were compared using log-rank tests. ResultsOf the 222 included patients, 111 (50%) were treated with 5-FU and 111 (50%) with capecitabine. Curative CRT was completed according to treatment plan in 77% of patients in the capecitabine-based group and 62% of the 5-FU group (p = 0.06). Adverse events (14 vs 21%, p = 0.29), 2-year OS (73% vs 61%, p = 0.07) and 2-year DFS (56% vs 50%, p = 0.50) did not differ significantly between groups. ConclusionsChemoradiotherapy with capecitabine and MMC is associated with a similar toxicity profile compared to 5-FU plus MMC and no difference in survival was found. Capecitabine-based CRT, as a more patient-friendly schedule, may be considered as an alternative to a 5-FU-based regimen.

High-risk patients with locally advanced non-small cell lung cancer treated with stereotactic body radiation therapy to the peripheral primary combined with conventionally fractionated volumetric arc therapy to the mediastinal lymph nodes.

A very narrow therapeutic window exists when delivering curative chemoradiotherapy for inoperable locally advanced non-small cell lung cancer (NSCLC), particularly when large distances exist between areas of gross disease in the thorax. In the present study, we hypothesize that a novel technique of stereotactic body radiation therapy (SBRT) to the primary tumor in combination with volumetric arc therapy (VMAT) to the mediastinal lymph nodes (MLN) is a suitable approach for high-risk patients with large volume geographically distant locally advanced NSCLC. In this single institutional review, we identified high-risk patients treated between 2014 and 2017 with SBRT to the parenchymal lung primary as well as VMAT to the involved MLN using conventional fractionation. Dosimetrically, comparative plans utilizing VMAT conventionally fractionated delivered to both the primary and MLN were analyzed. Clinically, toxicity (CTCAE version 5.0) and oncologic outcomes were analyzed in detail. A total of 21 patients were identified, 86% (n=18) of which received chemotherapy as a portion of their treatment. As treatment phase was between 2014 and 2017, none of the patients received consolidation immunotherapy. Target volume (PTV) dose coverage (99 vs. 87%) and CTV volume (307 vs. 441ml) were significantly improved with SBRT+MLN vs. for VMAT alone (p<0.0001). Moreover, low-dose lung (median V5Gy [%]: 71 vs. 77, p<0.0001), heart (median V5Gy [%]: 41 vs. 49, p<0.0001) and esophagus (median V30Gy [%]: 54 vs. 55, p=0.03) dose exposure were all significantly reduced with SBRT+MLN. In contrast, there was no difference observed in high-dose exposure of lungs, heart, and spinal cord. Following SBRT+MLN treatment, we identified only one case of high-grade pneumonitis. As expected, we observed a higher rate of esophagitis with a total of seven patients experience grade 2+ toxicity. Overall, there were no grade 4+ toxicities identified. After a median 3 years follow up, disease progression was observed in 70% of patients irradiated using SBRT+MLN, but never in the spared 'bridging' tissue between pulmonary SBRT and mediastinal VMAT. For high risk patients, SBRT+MLN is dosimetrically feasible and can provide an alternative to dose reductions necessitated by otherwise very large target volumes.

The Role of Age and Comorbidities in Esophagogastric Cancer Chemoradiation of the Frail Elderly (>70 Years): An Analysis from a Tertiary High Volume-Center

Elderly patients > 70 years of age with esophageal cancer (EC) represent a challenging group as frailty and comorbidities need to be considered. The aim of this retrospective study was to evaluate the efficacy and side effects of curative chemoradiation therapy (CRT) with regard to basic geriatric screening in elderly patients in order to elucidate prognostic factors. Thirty-four elderly patients > 70 years with EC treated at our cancer center between May 2014 and October 2018 fulfilled the selection criteria for this retrospective analysis. Treatment consisted of intravenous infusion of carboplatin/paclitaxel or fluorouracil (5-FU)/cisplatin with the intention of neoadjuvant or definite chemoradiation. Clinicopathological data including performance status (ECOG), (age-adjusted) Charlson comorbidity index (CCI), Frailty-scale by Fried, Mini Nutritional Assessment Short Form, body mass index, C-reactive protein to albumin ratio, and treatment-related toxicity (CTCAE) were assessed. Data were analyzed as predictors of overall survival (OS) and progression-free survival (PFS). All patients (ten female, 24 male) received combined CRT (22 patients in neoadjuvant, 12 patients in definite intent). Median age was 75 years and the ECOG index between 0 and 1 (52.9% vs. 35.3%); four patients were rated as ECOG 3 (11.8%). Median follow-up was 24 months. Tumors were mainly located in the lower esophagus or esophagogastric-junction with an T3 stage (n = 25; 75.8%) and N1 stage (n = 28; 90.3%). 15 patients (44.1%) had SCC, 19 patients (55.9%) AC. 26 of the patients (76.5%) were scored as prefrail and 50% were in risk for malnutrition (n = 17). In relation to the BMI, ten patients (29.4%) were ranked as overweight, and 15 patients were presented in a healthy state of weight (44.1%). Grade 3 acute toxicity (or higher) occured in nine cases (26.5%). Most of the patients did not show any late toxicities (66.7%). Trimodal therapy provides a significant prolonged OS (p = 0.049) regardless of age, but without impact on PFS. Our analysis suggests that chemoradiation therapy is feasible for elderly patients (>70 years) with tolerable toxicity. Trimodal therapy of EC shows a positive effect on OS and PFS. Further studies are needed to elucidate benefitting subgroups within the elderly. In addition to age, treatment decisions should be based on performance status, nutritional condition and multidisciplinary validated geriatric screening tools.

The Dutch Lung Cancer Audit-Radiotherapy (DLCA-R): Real-World Data on Stage III Non-Small Cell Lung Cancer Patients Treated With Curative Chemoradiation

IntroductionChemoradiotherapy (CRT) is the standard of care in inoperable non–small-cell lung cancer (NSCLC) patients, favoring concurrent (cCRT) over sequential CRT (seqCRT), with adjuvant immunotherapy in responders. Elderly and frail NSCLC patients have generally been excluded from trials in the past. In elderly patients however, the higher treatment related morbidity of cCRT, may outweigh the possible lower tumor control of seqCRT. For elderly patients with locally advanced NSCLC real-world data is essential to be able to balance treatment toxicity and treatment outcome. The aim of this study is to analyze acute toxicity and 3-month mortality of curative chemoradiation (CRT) in patients with stage III NSCLC and to analyze whether cCRT for elderly stage III NSCLC patients is safe. MethodsThe Dutch Lung Cancer Audit-Radiotherapy (DLCA-R) is a national lung cancer audit that started in 2013 for patients treated with curative intent radiotherapy. All Dutch patients treated for stage III NSCLC between 2015 and 2018 with seqCRT or cCRT for (primary or recurrent) stage III lung cancer are included in this population-based study. Information was collected on patient, tumor- and treatment characteristics and the incidence and severity of acute non-hematological toxicity (CTCAE-4 version 4.03) and mortality within 3 months after the end of radiotherapy. To evaluate the association between prognostic factors and outcome (acute toxicity and mortality within 3 months), an univariable and multivariable analysis was performed. The definition of cCRT was:radiotherapy started within 30 days after the start of chemotherapy. ResultsOut of all 20 Dutch departments of radiation oncology, 19 centers participated in the registry. A total of 2942 NSCLC stage III patients were treated with CRT. Of these 67.2% (n = 1977) were treated with cCRT (median age 66 years) and 32.8% (n = 965) were treated with seqCRT (median age 69 years). Good performance status (WHO 0-1) was scored in 88.6% for patients treated with cCRT and in 71.0% in the patients treated with seqCRT. Acute nonhematological 3-month toxicity (CTCAE grade ≥3 or radiation pneumonitis grade ≥2) was scored in 21.9% of the patients treated with cCRT and in 17.7% of the patients treated with seqCRT. The univariable analysis for acute toxicity showed significantly increased toxicity for cCRT (P = .008), WHO ≥2 (P = .006), and TNM IIIC (P = .031). The multivariable analysis for acute toxicity was significant for cCRT (P = .015), WHO ≥2 (P = .001) and TNM IIIC (P = .016). The univariable analysis for 3-month mortality showed significance for seqCRT (P = .025), WHO ≥2 (P < .001), higher cumulative radiotherapy dose (P < .001), higher gross tumor volume total (P = .020) and male patients (p < .001). None of these variables reached significance in the multivariable analysis for 3-month mortality. ConclusionIn this national lung cancer audit of inoperable NSCLC patients, 3-month toxicity was significantly higher in patients treated with cCRT (21.9% vs. 17.7% for seqCRT) higher TNM stage IIIC, and poor performance (WHO≥2) patients.The 3-months mortality was not significantly different for tested parameters. Age was not a risk factor for acute toxicity, nor 3 months mortality.

Chemoradiation for elderly patients (≥ 65 years) with esophageal cancer: a retrospective single-center analysis

BackgroundPresent studies on the efficacy and safety of curative chemoradiation therapy (CRT) with esophageal cancer reflect heterogenous results especially in elderly patients. The aim of this study was to evaluate the toxicity and efficacy of CRT in patients ≥ 65 years. In a cohort, the focus centered around treatment-related toxicity (CTCAE Grade > 3), overall survival as well as progression free survival, comparing these rates in-between patients older than 70 years to those younger than 70 years.MethodsA total of 67 patients older than 65 years (34 (50.7%) were older than 70 years) met the inclusion criteria for retrospective analysis (period from January 2013 to October 2017). Treatment consisted of radiotherapy and chemotherapy with carboplatin/paclitaxel or fluorouracil (5-FU)/cisplatin with the intention of neoadjuvant or definite chemoradiation. A sum of 67 patients received CRT (44 (65.6%) patients in neoadjuvant, 23 (34.4%) in definite intent). Of these, 22 and 12 patients were older than 70 years (50% and 52.2% in both treatment groups, respectively). Median age was 71 years and patients had a good physical performance status (ECOG 0: 57.6%, ECOG 1: 27.3%). Median follow-up was 24 months. Most patients had advanced tumour stages (T3 stage: n = 51, 79.7%) and nodal metastasis (N1 stage: n = 54, 88.5%). A subgroup comparison was conducted between patients aged ≤ 70 years and > 70 years.ResultsIn severe (CTCAE Grade 3–5) toxicities (acute and late), no significant differences were observed between both patient groups (< 70 years vs. > 70 years). 21% had acute grade 3 events, 4 patients (4%) had grade 4 events, and two patients (3%) had one grade 5 event. Late toxicity after CRT was grade 1 in 13 patients (22%), grade 2 in two (3%), grade 3 in two (3%), grade 4 in four (7%), and grade 5 in one (2%). Median overall survival (OS) of all patients was 30 months and median progression-free survival (PFS) was 16 months. No significant differences were seen for OS (32 months vs. 25 months; p = 0.632) and PFS (16 months vs. 12 months; p = 0.696) between older patients treated with curative intent and younger ones. Trimodal therapy significantly prolonged both OS and PFS (p = 0.005; p = 0.018), regardless of age.ConclusionCRT in elderly patients (≥ 65 years) with esophageal cancer is feasible and effective. Numbers for acute and late toxicities can be compared to cohorts of younger patients (< 65 years) with EC who received the same therapies. Age at treatment initiation alone should not be the determining factor. Instead, functional status, risk of treatment-related morbidities, life expectancy and patient´s preferences should factor into the choice of therapy.

Assessment of Interfraction Change in Gross Tumor Volume of Anal Carcinoma Patients Undergoing Curative Chemoradiotherapy

<h3>Purpose/Objective(s)</h3> Radiation with concurrent chemotherapy (CRT) represents standard definitive therapy for anal cancer. CRT protocols result in excellent local control but are associated with significant acute and late morbidity. Adaptive planning techniques may allow for decrease in treatment volume and reduce toxicity. In this study, we used serial MRI scans to assess changes in gross tumor volume (GTV) during curative CRT. <h3>Materials/Methods</h3> Since 2019, we have instituted a REB-approved prospective registry study of de-escalated radiotherapy for patients undergoing CRT for anal cancer. Patients received a total dose of 45-63 Gy in 25-35 fractions with concurrent Capecitabine and a single dose of Mitomycin-C on day 1. In addition to pre-treatment (pre-tx) CT and MR simulation, patients also underwent MR simulation at fraction 11 (fx11) and fraction 21 (fx21). The GTV was contoured separately on individual axial T2 sequences. Median (inter-quartile-range) was used for descriptive statistics and the Mann-Whitney-Wilcoxon was used between groups of interfractional contours to determine statistically significant differences in tumor size between fractions. The Kruskal-Wallace test was used to determine significance between all 3 GTV volumes. P-values of <0.05 were considered statistically significant. <h3>Results</h3> A total of 24 patients were accrued. All patient completed RT without interruptions. All 24 had pre-tx MRI. During CRT course, 22 had a second MRI scan (fx11), and 19 had a third (fx21) scan. Table 1 shows the median (IQR) pre-tx GTV and the absolute and percent reduction in the GTV at fx11 and fx21 compared to pre-treatment GTV. Median (IQR) reduction in GTV between pre-tx and fx11 and fx21 MRI was 6.1cc (3.8-12.1) and 7.8cc (5.7-14.6), respectively. Median reduction in GTV between fx11 and fx21 was 2.9cc (1.3-6.6). After normalizing volumes as the percentage of pre-tx GTV, median (IQR) volume was 62.5% (51.6-69.7) (p<0.001) at fx11 and 43.6% (34.2-55.6) (p<0.001) at fx21. Based on Kruskal-Wallace test, overall change between GTVs at all 3 time points was found to be significant, p=0.042. <h3>Conclusion</h3> For patients undergoing CRT for anal cancer, there appears to be an early and significant reduction in the tumor volume over time. This study helps define planning adaptation parameters using serial MRI during CRT and will inform strategies to reduce normal tissue exposure

Persistent lymph nodes after curative chemoradiotherapy for head and neck cancer: imaging predictors of response for decision-making.

To identify response predictors in patients with head and neck squamous cell carcinoma (N + HNSCC) and persistent lymph nodes after curative chemoradiotherapy treatment (CCRT). Consecutive patients with N + HNSCC treated with CCRT and persistent lymph nodes at first follow-up between 2015 and 2021 were identified and analyzed. Complete response was defined as the absence of lymph node metastatic involvement in patients with salvage lymphadenectomy or the absence of progression after 1 year of successive follow-ups. Tumour type and location, staging, and human papillomavirus (HPV) status were considered for analysis. The number and size of lymph nodes, type, shape, enhancement and margins on diagnostic and follow-up CT were also analyzed. The cohort included 46 patients with 134 pathological lymph nodes. Logistic regression models showed the following variables to be significant: performance of salvage lymphadenectomy (OR 0.094, [CI 95% 0.004-0.61], p = 0.037); the type of lymphadenopathy on diagnostic CE-CT (solid vs. cystic) (N1: OR = 4.11, [CI 95% 1.11-17.93], p = 0.042 and N3: OR 6.42, [CI 95% 1.2-42.56], p = 0.036); the change of shape (round to oval) on the follow-up CE-CT (OR 9.76, [CI 95% 1.79-8.57], p = 0.016) and the time in days between CCRT and the first follow-up CE-CT (OR 1.06, [CI 95% 1.004-1.13], p = 0.048). In our experience, the presence of solid lymph nodes on pre-treatment CT and the change in shape from round to oval on post-treatment CT are predictors of response to treatment in patients with N + HNSCC persistent lymph nodes after CCRT. Increasing the temporal interval between treatment and follow-up CT should be considered to avoid unnecessary nodal dissections.

511P HIV impact in localized anal carcinoma: A matched cohort study

Despite a higher incidence of HPV-related cancer in HIV-positive (HIV+) patients (pts), pivotal studies with curative chemoradiation (CRT) in anal cancer do not include this population. The impact of HIV infection remains unknown in this scenario. This study aimed to compare overall survival (OS) according to HIV status.