Patterns of Recurrence After Poor Response to Neoadjuvant Chemotherapy in Gastric Cancer and the Role for Adjuvant Radiation.

BACKGROUND: Improved treatment strategies are needed for patients with locally advanced gastric cancer with poor response to neoadjuvant chemotherapy. We aimed to describe patterns of failure for patients with no or partial response (NR, PR) to preoperative chemotherapy. PATIENTS AND METHODS: We analyzed patients with locally advanced gastric cancer treated from 2008 to 2022 with preoperative chemotherapy followed by surgery with D2 resection. We excluded patients who received radiation. Cumulative incidence of locoregional failure (LRF) and distant metastases (DM) were calculated. For patients with recurrent abdominal disease, hypothetical radiation clinical treatment volumes (CTV) were contoured on postoperative scans and compared with patterns of recurrence. RESULTS: A total of 60 patients were identified. The most used preoperative chemotherapy was FLOT (38.6%), followed by FOLFOX (30%) and ECF/ECX/EOX (23.3%). Four (6.7%), 40 (66.7%), and 9 patients (15%) had a complete pathologic response (CR), PR, and NR to neoadjuvant therapy, respectively. Among patients without a CR, 3-year overall and progression-free survival rates were 62.3% (95% CI 48-76.6%) and 51.3% (95% CI 36.9-65.7%), respectively. Three-year cumulative incidence of LRF and DM were 8.4% (95% CI 0.4-16.4%) and 41.0% (95% CI 26.3-55.4%), respectively. Absolute rates of patients having the first site of recurrence encompassed by a postoperative radiation CTV was 2.0% for patients without a CR and 0% for patients with NR. CONCLUSIONS: Patients with locally advanced gastric cancer with less than a CR to chemotherapy have poor outcomes due to high rates of DM. Adjuvant locoregional therapy such as radiation is unlikely to affect survival.

Impact of Delaying Surgery After Chemoradiation on Outcomes for Locally Advanced Esophageal Squamous Cell Carcinoma.

BACKGROUND: Performing selective esophagectomy for locally advanced squamous cell carcinoma may spare patients morbidity, but delayed surgery may infer higher risks. This study evaluated the impact of length of time between chemoradiation and esophagectomy on perioperative outcomes and long-term survival. METHODS: The impact of surgical timing, stratified by surgery performed < 180 and ≥ 180 days from starting radiation, on perioperative outcomes and survival in patients treated with chemoradiation and esophagectomy for cT1N + M0 and cT2-4, any N, M0 squamous cell carcinoma of the mid-distal esophagus in the National Cancer Database (2006-2016) was evaluated with logistic regression, Kaplan-Meier curves, Cox proportional-hazards methods, and propensity-matched analysis. RESULTS: Median time between starting radiation and esophagectomy in 1641 patients was 93 (IQR 81-114) days. Most patients (96.8%, n = 1589) had surgery within 180 days of starting radiation, while 52 patients (3.2%) had delayed surgery. Black race and clinical T stage were associated with delayed surgery. Rates of pathologic upstaging, downstaging, complete response, and positive margins were not significantly different between the groups. Patients with delayed surgery had increased major morbidity as measured by a composite of length of hospital stay, readmission, and 30-day mortality [42.3% (22/52) vs 22.3% (355/1589), p = 0.001]. However, delayed surgery was not associated with a significant difference in survival in both univariate [5-year survival 32.8% (95% CI 21.1-50.7) vs 47.3% (44.7-50.1), p = 0.19] and multivariable analysis [hazard ratio (HR) 1.23 (0.85-1.78), p = 0.26]. CONCLUSIONS: Delaying surgery longer than 180 days after starting chemoradiation for esophageal squamous cell carcinoma is associated with worse perioperative outcomes but not long-term survival.

Validation of NRG Oncology's prognostic nomograms for oropharyngeal cancer in the Veterans Affairs database.

BACKGROUND: To test whether nomograms developed by NRG Oncology for oropharyngeal squamous cell carcinoma (OPSCC) patients could be validated in an independent population-based sample. METHODS: The authors tested nomograms for estimating progression-free survival (PFS) and overall survival (OS) in patients from the Veterans Health Administration with previously untreated locoregionally advanced OPSCC, diagnosed between 2008 and 2017, managed with definitive radiotherapy with or without adjuvant systemic therapy. Covariates were age, performance status, p16 status, T/N category, smoking history, education history, weight loss, marital status, and anemia. We used multiple imputation to handle missing data and performed sensitivity analyses on complete cases. Validation was assessed via Cox proportional hazards models, log-rank tests, and c-indexes. RESULTS: A total of 4007 patients met inclusion criteria (658 patients had complete data). Median follow-up time was 3.20 years, with 967 progression events and 471 noncancer deaths. Each risk score was associated with poorer outcomes per unit increase (PFS score, hazard ratio [HR], 1.42 [1.37-1.47]; OS score, HR, 1.40 [1.34-1.45]). By risk score quartile, 2-year PFS estimates were 89.2%, 78.5%, 65.8%, and 48.3%; OS estimates were 92.6%, 83.6%, 73.9%, and 51.3%, respectively (P < .01 for all comparisons). C-indices for models of PFS and OS were 0.65 and 0.67, for all patients, respectively (0.69 and 0.73 for complete cases). The nomograms slightly overestimated PFS and OS in the overall cohort but exhibited high agreement in complete cases. CONCLUSIONS: NRG nomograms were effective for predicting PFS and OS for patients with OPSCC, supporting their broader applicability in the OPSCC population undergoing definitive radiotherapy.

Validation of an oncology-specific opioid risk calculator in cancer survivors.

BACKGROUND: Clinical guidelines recommend that providers risk-stratify patients with cancer before prescribing opioids. Prior research has demonstrated that a simple cancer opioid risk score might help identify to patients with cancer at the time of diagnosis with a high likelihood of long-term posttreatment opioid use. This current project validates this cancer opioid risk score in a generalizable, population-based cohort of elderly cancer survivors. METHODS: This study identified 44,932 Medicare beneficiaries with cancer who had received local therapy. Longitudinal opioid use was ascertained from Medicare Part D data. A risk score was calculated for each patient, and patients were categorized into low-, moderate-, and high-risk groups on the basis of the predicted probability of persistent opioid use. Model discrimination was assessed with receiver operating characteristic curves. RESULTS: In the study cohort, 5.2% of the patients were chronic opioid users 1 to 2 years after the initiation of cancer treatment. The majority of the patients (64%) were at low risk and had a 1.2% probability of long-term opioid use. Moderate-risk patients (33% of the cohort) had a 5.6% probability of long-term opioid use. High-risk patients (3.5% of the cohort) had a 75% probability of long-term opioid use. The opioid risk score had an area under the receiver operating characteristic curve of 0.869. CONCLUSIONS: This study found that a cancer opioid risk score could accurately identify individuals with a high likelihood of long-term opioid use in a large, generalizable cohort of cancer survivors. Future research should focus on the implementation of these scores into clinical practice and how this could affect prescriber behavior and patient outcomes. LAY SUMMARY: A novel 5-question clinical decision tool allows physicians treating patients with cancer to accurately predict which patients will persistently be using opioid medications after completing therapy.

Survival of African American and non-Hispanic white men with prostate cancer in an equal-access health care system.

BACKGROUND: African American (AA) men in the general US population are more than twice as likely to die of prostate cancer (PC) compared with non-Hispanic white (NHW) men. The authors hypothesized that receiving care through the Veterans Affairs (VA) health system, an equal-access medical system, would attenuate this disparity. METHODS: A longitudinal, centralized database of >20 million veterans was used to assemble a cohort of 60,035 men (18,201 AA men [30.3%] and 41,834 NHW men [69.7%]) who were diagnosed with PC between 2000 and 2015. RESULTS: AA men were more likely to live in regions with a lower median income ($40,871 for AA men vs $48,125 for NHW men; P < .001) and lower high school graduation rates (83% for AA men vs 88% for NHW men; P < .001). At the time of diagnosis, AA men were younger (median age, 63.0 years vs 66.0 years; P < .001) and had a higher prostate-specific antigen level (median, 6.7 ng/mL vs 6.2 ng/mL; P < .001), but were less likely to have Gleason score 8 to 10 disease (18.8% among AA men vs 19.7% among NHW men; P < .001), a clinical T classification ≥3 (2.2% vs 2.9%; P < .001), or distant metastatic disease (2.7% vs 3.1%; P = 0.01). The 10-year PC-specific mortality rate was slightly lower for AA men (4.4% vs 5.1%; P = .005), which was confirmed in multivariable competing-risk analysis (subdistribution hazard ratio, 0.85; 95% CI, 0.78-0.93; P < .001). CONCLUSIONS: AA men diagnosed with PC in the VA health system do not appear to present with more advanced disease or experience worse outcomes compared with NHW men, in contrast to national trends, suggesting that access to care is an important determinant of racial equity.

Predictive classifier for intensive treatment of head and neck cancer.

BACKGROUND: This study was designed to test the hypothesis that the effectiveness of intensive treatment for locoregionally advanced head and neck cancer (LAHNC) depends on the proportion of patients' overall event risk attributable to cancer. METHODS: This study analyzed 22,339 patients with LAHNC treated in 81 randomized trials testing altered fractionation (AFX; Meta-Analysis of Radiotherapy in Squamous Cell Carcinomas of Head and Neck [MARCH] data set) or chemotherapy (Meta-Analysis of Chemotherapy in Head and Neck Cancer [MACH-NC] data set). Generalized competing event regression was applied to the control arms in MARCH, and patients were stratified by tertile according to the ω score, which quantified the relative hazard for cancer versus competing events. The classifier was externally validated on the MACH-NC data set. The study tested for interactions between the ω score and treatment effects on overall survival (OS). RESULTS: Factors associated with a higher ω score were a younger age, a better performance status, an oral cavity site, higher T and N categories, and a p16-negative/unknown status. The effect of AFX on OS was greater in patients with high ω scores (hazard ratio [HR], 0.92; 95% confidence interval [CI], 0.85-0.99) and medium ω scores (HR, 0.91; 95% CI, 0.84-0.98) versus low ω scores (HR, 0.97; 95% CI, 0.90-1.05; P for interaction = .086). The effect of chemotherapy on OS was significantly greater in patients with high ω scores (HR, 0.81; 95% CI, 0.75-0.88) and medium ω scores (HR, 0.86; 95% CI, 0.78-0.93) versus low ω scores (HR, 0.96; 95% CI, 0.86-1.08; P for interaction = .011). CONCLUSIONS: LAHNC patients with a higher risk of cancer progression relative to competing mortality, as reflected by a higher ω score, selectively benefit from more intensive treatment.

Combined Androgen Blockade in Localized Prostate Cancer Treated With Definitive Radiation Therapy.

BACKGROUND: The addition of androgen deprivation therapy to radiation therapy (RT) improves survival in patients with intermediate- and high-risk prostate cancer (PCa), but it is not known whether combined androgen blockade (CAB) with a gonadotropin-releasing hormone agonist (GnRH-A) and a nonsteroidal antiandrogen improves survival over GnRH-A monotherapy. METHODS: This study evaluated patients with intermediate- and high-risk PCa diagnosed in 2001 through 2015 who underwent RT with either GnRH-A alone or CAB using the Veterans Affairs Informatics and Computing Infrastructure. Associations between CAB and prostate cancer-specific mortality (PCSM) and overall survival (OS) were determined using multivariable regression with Fine-Gray and multivariable Cox proportional hazards models, respectively. For a positive control, the effect of long-term versus short-term GnRH-A therapy was tested. RESULTS: The cohort included 8,423 men (GnRH-A, 4,529; CAB, 3,894) with a median follow-up of 5.9 years. There were 1,861 deaths, including 349 resulting from PCa. The unadjusted cumulative incidences of PCSM at 10 years were 5.9% and 6.9% for those receiving GnRH-A and CAB, respectively (P=.16). Compared with GnRH-A alone, CAB was not associated with a significant difference in covariate-adjusted PCSM (subdistribution hazard ratio [SHR], 1.05; 95% CI, 0.85-1.30) or OS (hazard ratio, 1.02; 95% CI, 0.93-1.12). For high-risk patients, long-term versus short-term GnRH-A therapy was associated with improved PCSM (SHR, 0.74; 95% CI, 0.57-0.95) and OS (SHR, 0.82; 95% CI, 0.73-0.93). CONCLUSIONS: In men receiving definitive RT for intermediate- or high-risk PCa, CAB was not associated with improved PCSM or OS compared with GnRH alone.

Patient Selection and Outcomes for Hypofractionated Accelerated Radiation and Concurrent Chemotherapy for Non-Small-Cell Lung Cancer.

PURPOSE/OBJECTIVES: Adoption of hypofractionated accelerated radiation therapy (HART) with concurrent chemotherapy has been limited by toxicity concerns. We aimed to describe outcomes of patients treated with HART and concurrent chemotherapy and to evaluate dosimetry to organs at risk to guide patient selection. MATERIALS/METHODS: We evaluated a retrospective cohort of NSCLC patients treated with concurrent chemotherapy with HART (>2.2 Gy per fraction) or standard fractionated radiation therapy (SFRT; 2-2.2 Gy fractions). Dosimetric parameters to key organs at risk were compared, and toxicity, patterns of recurrence and survival were calculated for the cohorts. RESULTS: Fifty-three patients treated with HART were compared with 100 patients treated with SFRT. Median dose per fraction for the HART cohort was 2.75 Gy (range 2.4-3 Gy). HART patients had significantly lower doses to the lung, heart, and esophagus due to patient selection. The HART group and had rates of grade 2+ pneumonitis (9.4 vs. 19%, P = .16) and grade 2+ esophagitis (20.8 vs. 45%, P < .01) that compared favorably to SFRT. Cumulative incidence of in-field recurrence trended lower in the HART cohort (7.6% vs. 23.1%, P = .058). Among the HART group, 88.7% (47/53) met the newly proposed lung constraints based on the degree of hypofractionation CONCLUSION: In select patients with favorable dosimetry to organs at risk, definitive HART with concurrent chemotherapy achieved excellent local control with low toxicity. These results are being used to inform a prospective study on the safety and efficacy of HART with concurrent chemotherapy for select NSCLC patients.

Safety of Pelvic and Abdominal Radiation Therapy for Patients With Inflammatory Bowel Disease: A Dosimetric Analysis of Acute Bowel Toxicity.

PURPOSE: Inflammatory bowel disease (IBD) has been considered a relative contraindication to radiation therapy (RT) because of the potential greater risk of RT-induced toxicities. This study aimed to assess acute toxicity outcomes in patients with IBD treated with abdominal/pelvic RT. METHODS AND MATERIALS: After institutional review board approval, patients with IBD who received RT to the abdomen/pelvis were identified from an institutional research repository, and their electronic medical records were reviewed. The IBD cohort was matched 1:1 with controls according to all of the following: RT, gender, disease site, age, and year of RT. Acute toxicity was defined as toxicity occurring within 3 months of RT. Primary outcomes were assessed via univariable logistic regression models and the predicted probability of acute toxicity and acute gastrointestinal (GI) toxicity were plotted for the most significant covariates. IBD and control cohorts were compared on demographic and toxicity variables using χ2/Fisher exact tests and Kruskal-Wallis tests where appropriate. RESULTS: We identified 62 patients with a median age of 64 years (IQR, 54-70 years) who received RT from 2006 to 2022. Patients were treated with intensity modulated RT (38; 61.3%), 3-dimensional conformal RT (12; 19.4%), and stereotactic body RT/brachytherapy (12; 19.4%). After RT, 28 (45.2%) and 23 (37.1%) patients experienced grade ≥2 acute (any) and acute GI toxicity, respectively. Higher overall RT dose and RT dose to small bowel were found to be significantly associated with increased risk of grade ≥2 acute toxicities (OR, 1.041 per unit Gy; 95% CI, 1.005-1.084; P = .034 and OR, 1.046; 95% CI, 1.018-1.082; P = .003, respectively). Between IBD and control cohorts, there were no significant differences in grade ≥2 acute (any) and acute GI toxicities (P = .710 and P = .704, respectively). CONCLUSIONS: In patients with IBD treated with abdominal/pelvic RT for malignancy, RT was effective and well-tolerated. RT treatment planning should carefully consider the location(s) of IBD inflammation and dose to bowel structures, in particular, dose to the small bowel.

Lung Cancer Survival Trends in the Veterans Health Administration.

INTRODUCTION: Lung cancer survival is improving in the United States. We investigated whether there was a similar trend within the Veterans Health Administration (VHA), the largest integrated healthcare system in the United States. MATERIALS AND METHODS: Data from the Veterans Affairs Central Cancer Registry were analyzed for temporal survival trends using Kaplan-Meier estimates and linear regression. RESULTS: A total number of 54,922 Veterans were identified with lung cancer diagnosed from 2010 to 2017. Histologies were classified as non-small-cell lung cancer (NSCLC) (64.2%), small cell lung cancer (SCLC) (12.9%), and 'other' (22.9%). The proportion with stage I increased from 18.1% to 30.4%, while stage IV decreased from 38.9% to 34.6% (both P < .001). The 3-year overall survival (OS) improved for stage I (58.6% to 68.4%, P < .001), stage II (35.5% to 48.4%, P < .001), stage III (18.7% to 29.4%, P < .001), and stage IV (3.4% to 7.8%, P < .001). For NSCLC, the median OS increased from 12 to 21 months (P < .001), and the 3-year OS increased from 24.1% to 38.3% (P < .001). For SCLC, the median OS remained unchanged (8 to 9 months, P = .10), while the 3-year OS increased from 9.1% to 12.3% (P = .014). Compared to White Veterans, Black Veterans with NSCLC had similar OS (P = .81), and those with SCLC had higher OS (P = .003). CONCLUSION: Lung cancer survival is improving within the VHA. Compared to White Veterans, Black Veterans had similar or higher survival rates. The observed racial equity in outcomes within a geographically and socioeconomically diverse population warrants further investigation to better understand and replicate this achievement in other healthcare systems.

Personalized Accelerated ChEmoRadiation (PACER) for Lung Cancer: Protocol for a Bayesian Optimal Phase I/II Trial.

INTRODUCTION: Prior attempts to escalate radiation dose for non-small cell lung cancer (NSCLC) have not improved survival. Given the high risk for cardiopulmonary toxicity with treatment and heterogenous presentation of locally advanced NSCLC, it is unlikely that a single dose regimen is optimal for all patients. This phase I/II trial aims to evaluate a novel treatment approach where the level of accelerated hypofractionation is determined by the predicted toxicity from dose to organs at risk (OARs). METHODS: Patients ≥ 18 years old with lung cancer planned for fractionated radiotherapy to the lung with concurrent chemotherapy will be eligible. Radiation therapy (RT) will be delivered to a total dose of 60 to 66 Gy in 30, 25, or 20 fractions depending on the ability to meet constraints to key organs at risk including the lungs, heart, and esophagus. The primary endpoint is high grade pulmonary, esophageal, or cardiac toxicity. A Bayesian optimized design is used to determine stopping boundaries and evaluate the primary endpoint. CONCLUSION: PACER will evaluate the safety and feasibility of personalized accelerated chemoradiotherapy for lung cancer.

BIOGUIDE-X: A First-in-Human Study of the Performance of Positron Emission Tomography-Guided Radiation Therapy.

PURPOSE: Positron emission tomography (PET)-guided radiation therapy is a novel tracked dose delivery modality that uses real-time PET to guide radiation therapy beamlets. The BIOGUIDE-X study was performed with sequential cohorts of participants to (1) identify the fluorodeoxyglucose (FDG) dose for PET-guided therapy and (2) confirm that the emulated dose distribution was consistent with a physician-approved radiation therapy plan. METHODS AND MATERIALS: This prospective study included participants with at least 1 FDG-avid targetable primary or metastatic tumor (2-5 cm) in the lung or bone. For cohort I, a modified 3 + 3 design was used to determine the FDG dose that would result in adequate signal for PET-guided therapy. For cohort II, PET imaging data were collected on the X1 system before the first and last fractions among patients undergoing conventional stereotactic body radiation therapy. PET-guided therapy dose distributions were modeled on the patient's computed tomography anatomy using the collected PET data at each fraction as input to an "emulated delivery" and compared with the physician-approved plan. RESULTS: Cohort I demonstrated adequate FDG activity in 6 of 6 evaluable participants (100.0%) with the first injected dose level of 15 mCi FDG. In cohort II, 4 patients with lung tumors and 5 with bone tumors were enrolled, and evaluable emulated delivery data points were collected for 17 treatment fractions. Sixteen of the 17 emulated deliveries resulted in dose distributions that were accurate with respect to the approved PET-guided therapy plan. The 17th data point was just below the 95% threshold for accuracy (dose-volume histogram score = 94.6%). All emulated fluences were physically deliverable. No toxicities were attributed to multiple FDG administrations. CONCLUSIONS: PET-guided therapy is a novel radiation therapy modality in which a radiolabeled tumor can act as its own fiducial for radiation therapy targeting. Emulated therapy dose distributions calculated from continuously acquired real-time PET data were accurate and machine-deliverable in tumors that were 2 to 5 cm in size with adequate FDG signal characteristics.

Chest wall pain after single-fraction thoracic stereotactic ablative Radiotherapy: Dosimetric analysis from the iSABR trial.

BACKGROUND AND PURPOSE: Concerns over chest wall toxicity has led to debates on treating tumors adjacent to the chest wall with single-fraction stereotactic ablative radiotherapy (SABR). We performed a secondary analysis of patients treated on the prospective iSABR trial to determine the incidence and grade of chest wall pain and modeled dose-response to guide radiation planning and estimate risk. MATERIALS AND METHODS: This analysis included 99 tumors in 92 patients that were treated with 25 Gy in one fraction on the iSABR trial which individualized dose by tumor size and location. Toxicity events were prospectively collected and graded based on the CTCAE version 4. Dose-response modeling was performed using a logistic model with maximum likelihood method utilized for parameter fitting. RESULTS: There were 22 grade 1 or higher chest wall pain events, including five grade 2 events and zero grade 3 or higher events. The volume receiving at least 11 Gy (V11Gy) and the minimum dose to the hottest 2 cc (D2cc) were most highly correlated with toxicity. When dichotomized by an estimated incidence of ≥ 20 % toxicity, the D2cc > 17 Gy (36.6 % vs. 3.7 %, p < 0.01) and V11Gy > 28 cc (40.0 % vs. 8.1 %, p < 0.01) constraints were predictive of chest wall pain, including among a subset of patients with tumors abutting or adjacent to the chest wall. CONCLUSION: For small, peripheral tumors, single-fraction SABR is associated with modest rates of low-grade chest wall pain. Proximity to the chest wall may not contraindicate single fractionation when using highly conformal, image-guided techniques with sharp dose gradients.

Redefining Candidates for Deintensification in Locoregionally Advanced P16+ Oropharyngeal Cancer Based on Relative Risk.

PURPOSE: Randomized trials have found that patients with locoregionally advanced p16+ oropharyngeal squamous cell carcinoma (OPSCC) do not benefit from treatment deintensification, even among favorable risk groups. Although various methods have been used to identify candidates for treatment deintensification, the optimal approach is unknown. METHODS AND MATERIALS: We conducted a multi-institutional cohort study of 444 patients with previously untreated p16+ OPSCC undergoing definitive radiation therapy with or without systemic therapy between 2009 and 2022. We compared the following 2 approaches for identifying candidates for deintensification: (1) favorable versus unfavorable risk, using NRG-HN005 eligibility criteria, and (2) low versus high relative risk of cancer events, using the Head and Neck Cancer Intergroup predictive classifier ("omega score"). We tested differences in outcomes and systemic therapy allocation by risk group using multivariable Cox models, competing event models, and logistic regression, and compared characteristics of hypothetical deintensification trials using the 2 approaches. Progression-free survival events were defined as cancer recurrence (locoregional or distant) or death from any cause. RESULTS: Median follow-up time was 52 months; 120 patients (27.0%) were favorable risk; a different 120 patients had low omega score; 28 patients (6.3%) met both criteria; 184 patients (41.4%) had discordant classification. On ordinal logistic regression, decreasing omega score was associated with a statistically significantly lower odds of receiving intensive therapy (normalized odds ratio, 0.37 per SD; 95% CI, 0.24-0.57), with a greater magnitude than favorable risk group (odds ratio, 0.66; 95% CI, 0.44-0.99). Among patients receiving cisplatin and/or platinum-based induction (n = 374), favorable risk was associated with significantly improved progression-free survival (hazard ratio, 0.59; 95% CI, 0.36-0.99), whereas lower omega score was associated with a significantly decreased relative hazard for cancer events (relative hazard ratio, 0.18; 95% CI, 0.070-0.46). In simulations, selecting patients with low omega scores increased the efficiency of hypothetical noninferiority trials. CONCLUSIONS: Considering patients' relative risk of cancer events can help define optimal populations for treatment deintensification in p16+ OPSCC.

A phase 2 single-arm trial of high-dose precision targeted radiotherapy added to immunotherapy for patients with metastatic non-small cell lung cancer.

HYPOTHESIS: For metastatic non-small cell lung cancer (NSCLC), the addition of radiotherapy (RT) to immune checkpoint inhibitor (ICI) therapy could have synergistic anti-cancer effects and address the most threatening tumors. We posited that the addition of high-dose RT to ICI could prolong progression-free survival (PFS). METHODS: In this single arm phase 2 trial, 45 patients with metastatic NSCLC who had received an anti-PD-1/anti-PD-L-1 ICI for 4+ weeks were enrolled from July 2017-May 2021. Patients received high-dose RT to 1-4 extracranial tumors and continued ICI until progression or unacceptable toxicity. The primary endpoint was PFS at 24 weeks, comparing to a historical control rate of 35%. RESULTS: Of 44 evaluable patients, median age was 71, 75% had adenocarcinoma, 64% had polymetastatic disease, and 85% of cancers with known PD-L1 percentage were PD-L1 positive. Median number of treated tumors was two and most common dose was 40 Gy in 10 fractions (41/81 tumors). Median follow-up was 23.3 months. The trial met the primary outcome: 24-week PFS was 60% (95% CI 44-75%), higher than the historical control rate (p<0.001). Median PFS was 6.9 months (95% CI 4.0-13.5 mo) and median OS was 27.4 months (95% CI 20.4-not reached). Several patients with pre-study disease progression on ICI treatment achieved durable responses to study treatment, up to 53 months. Local recurrence rate was low: cumulative incidence of 5% at one, two, and three years. Two dose-limiting toxicities were observed (5%), including one grade 5 pneumonitis. CONCLUSIONS: The strategy improved 24-week PFS compared to historical controls receiving ICI alone. The excellent local control supports the efficacy of high-dose RT in addressing macroscopic disease.

Neoadjuvant Therapy in the Post-German Rectal Trial Era: Making Sense in the Absence of Consensus.

Trimodality therapy per the German Rectal Trial has led to excellent locoregional outcomes for locally advanced rectal cancer. Recent efforts have shifted toward improving distant control and health-related quality of life in this disease. To this end, total neoadjuvant therapy has become an increasingly used approach in which most, if not all, chemotherapy is delivered before surgery to improve compliance and to address micrometastases early. To avoid surgical morbidity, a "watch-and-wait" approach, in which total mesorectal excision is deferred, has also been studied for patients who achieve a clinical complete response after chemoradiation. These 2 concurrent treatment trends have raised many points of uncertainty in what used to be a relatively straightforward neoadjuvant treatment paradigm. We discuss here our approach to neoadjuvant therapy for locally advanced rectal cancer, based on the data we currently have and through shared decision-making with patients to help them select the treatment that best aligns with their preferences and values.

Risk of developing subsequent primary lung cancer after receiving radiation for breast cancer.

Background: Radiotherapy (RT) is integral to breast cancer treatment, especially in the current era that emphasizes breast conservation. The aim of our study was to determine the incidence of subsequent primary lung cancer after RT exposure for breast cancer over a time span of 3 decades to quantify this risk over time as modern oncologic treatment continues to evolve. Methods: The SEER (Surveillance, Epidemiology, and End Results) database was queried from 1988 to 2014 for patients diagnosed with nonmetastatic breast cancer. Patients who subsequently developed primary lung cancer were identified. Multivariable regression modeling was performed to identify independent factors associated with the development of lung cancer stratified by follow up intervals of 5 to 9 years, 10 to 15 years, and >15 years after breast cancer diagnosis. Results: Of the 612,746 patients who met our inclusion criteria, 319,014 (52%) were irradiated. primary lung cancer developed in 5556 patients (1.74%) in the RT group versus 4935 patients (1.68%) in the non-RT group. In a multivariable model stratified by follow-up duration, the overall HR of developing subsequent ipsilateral lung cancer in the RT group was 1.14 (P = .036) after 5 to 9 years of follow-up, 1.28 (P = .002) after 10 to 15 years of follow-up, and 1.30 (P = .014) after >15 years of follow-up. The HR of contralateral lung cancer was not increased at any time interval. Conclusions: The increased risk of developing a primary lung cancer secondary to RT exposure for breast cancer is much lower than previously published. Modern RT techniques may have contributed to the improved risk profile, and this updated study is important for counseling and surveillance of breast cancer patients.