Survival in Patients With Brain Metastases: Summary Report on the Updated Diagnosis-Specific Graded Prognostic Assessment and Definition of the Eligibility Quotient

PURPOSE

Conventional wisdom has rendered patients with brain metastases ineligible for clinical trials for fear that poor survival could mask the benefit of otherwise promising treatments. Our group previously published the diagnosis-specific Graded Prognostic Assessment (GPA). Updates with larger contemporary cohorts using molecular markers and newly identified prognostic factors have been published. The purposes of this work are to present all the updated indices in a single report to guide treatment choice, stratify research, and define an eligibility quotient to expand eligibility.

METHODS

A multi-institutional database of 6,984 patients with newly diagnosed brain metastases underwent multivariable analyses of prognostic factors and treatments associated with survival for each primary site. Significant factors were used to define the updated GPA. GPAs of 4.0 and 0.0 correlate with the best and worst prognoses, respectively.

RESULTS

Significant prognostic factors varied by diagnosis and new prognostic factors were identified. Those factors were incorporated into the updated GPA with robust separation (P < .01) between subgroups. Survival has improved, but varies widely by GPA for patients with non-small-cell lung, breast, melanoma, GI, and renal cancer with brain metastases from 7-47 months, 3-36 months, 5-34 months, 3-17 months, and 4-35 months, respectively.

CONCLUSION

Median survival varies widely and our ability to estimate survival for patients with brain metastases has improved. The updated GPA (available free at brainmetgpa.com) provides an accurate tool with which to estimate survival, individualize treatment, and stratify clinical trials. Instead of excluding patients with brain metastases, enrollment should be encouraged and those trials should be stratified by the GPA to ensure those trials make appropriate comparisons. Furthermore, we recommend the expansion of eligibility to allow for the enrollment of patients with previously treated brain metastases who have a 50% or greater probability of an additional year of survival (eligibility quotient > 0.50).

Beyond an Updated Graded Prognostic Assessment (Breast GPA): A Prognostic Index and Trends in Treatment and Survival in Breast Cancer Brain Metastases From 1985 to Today

PURPOSE

Brain metastases are a common sequelae of breast cancer. Survival varies widely based on diagnosis-specific prognostic factors (PF). We previously published a prognostic index (Graded Prognostic Assessment [GPA]) for patients with breast cancer with brain metastases (BCBM), based on cohort A (1985-2007, n = 642), then updated it, reporting the effect of tumor subtype in cohort B (1993-2010, n = 400). The purpose of this study is to update the Breast GPA with a larger contemporary cohort (C) and compare treatment and survival across the 3 cohorts.

METHODS AND MATERIALS

A multi-institutional (19), multinational (3), retrospective database of 2473 patients with breast cancer with newly diagnosed brain metastases (BCBM) diagnosed from January 1, 2006, to December 31, 2017, was created and compared with prior cohorts. Associations of PF and treatment with survival were analyzed. Kaplan-Meier survival estimates were compared with log-rank tests. PF were weighted and the Breast GPA was updated such that a GPA of 0 and 4.0 correlate with the worst and best prognoses, respectively.

RESULTS

Median survival (MS) for cohorts A, B, and C improved over time (from 11, to 14 to 16 months, respectively; P < .01), despite the subtype distribution becoming less favorable. PF significant for survival were tumor subtype, Karnofsky Performance Status, age, number of BCBMs, and extracranial metastases (all P < .01). MS for GPA 0 to 1.0, 1.5-2.0, 2.5-3.0, and 3.5-4.0 was 6, 13, 24, and 36 months, respectively. Between cohorts B and C, the proportion of human epidermal receptor 2 + subtype decreased from 31% to 18% (P < .01) and MS in this subtype increased from 18 to 25 months (P < .01).

CONCLUSIONS

MS has improved modestly but varies widely by diagnosis-specific PF. New PF are identified and incorporated into an updated Breast GPA (free online calculator available at brainmetgpa.com). The Breast GPA facilitates clinical decision-making and will be useful for stratification of future clinical trials. Furthermore, these data suggest human epidermal receptor 2-targeted therapies improve clinical outcomes in some patients with BCBM.

Estrogen/progesterone receptor and HER2 discordance between primary tumor and brain metastases in breast cancer and its effect on treatment and survival

BACKGROUND

Breast cancer treatment is based on estrogen receptors (ERs), progesterone receptors (PRs), and human epidermal growth factor receptor 2 (HER2). At the time of metastasis, receptor status can be discordant from that at initial diagnosis. The purpose of this study was to determine the incidence of discordance and its effect on survival and subsequent treatment in patients with breast cancer brain metastases (BCBM).

METHODS

A retrospective database of 316 patients who underwent craniotomy for BCBM between 2006 and 2017 was created. Discordance was considered present if the ER, PR, or HER2 status differed between the primary tumor and the BCBM.

RESULTS

The overall receptor discordance rate was 132/316 (42%), and the subtype discordance rate was 100/316 (32%). Hormone receptors (HR, either ER or PR) were gained in 40/160 (25%) patients with HR-negative primary tumors. HER2 was gained in 22/173 (13%) patients with HER2-negative primary tumors. Subsequent treatment was not adjusted for most patients who gained receptors-nonetheless, median survival (MS) improved but did not reach statistical significance (HR, 17-28 mo, P = 0.12; HER2, 15-19 mo, P = 0.39). MS for patients who lost receptors was worse (HR, 27-18 mo, P = 0.02; HER2, 30-18 mo, P = 0.08).

CONCLUSIONS

Receptor discordance between primary tumor and BCBM is common, adversely affects survival if receptors are lost, and represents a missed opportunity for use of effective treatments if receptors are gained. Receptor analysis of BCBM is indicated when clinically appropriate. Treatment should be adjusted accordingly.

KEY POINTS

1. Receptor discordance alters subtype in 32% of BCBM patients.2. The frequency of receptor gain for HR and HER2 was 25% and 13%, respectively.3. If receptors are lost, survival suffers. If receptors are gained, consider targeted treatment.

A multi-center analysis of single-fraction versus hypofractionated stereotactic radiosurgery for the treatment of brain metastasis

Background

Hypofractionated-SRS (HF-SRS) may allow for improved local control and a reduced risk of radiation necrosis compared to single-fraction-SRS (SF-SRS). However, data comparing these two treatment approaches are limited. The purpose of this study was to compare clinical outcomes between SF-SRS versus HF-SRS across our multi-center academic network.

Methods

Patients treated with SF-SRS or HF-SRS for brain metastasis from 2013 to 2018 across 5 radiation oncology centers were retrospectively reviewed. SF-SRS dosing was standardized, whereas HF-SRS dosing regimens were variable. The co-primary endpoints of local control and radiation necrosis were estimated using the Kaplan Meier method. Multivariate analysis using Cox proportional hazards modeling was performed to evaluate the impact of select independent variables on the outcomes of interest. Propensity score adjustments were used to reduce the effects confounding variables. To assess dose response for HF-SRS, Biologic Effective Dose (BED) assuming an α/β of 10 (BED₁₀) was used as a surrogate for total dose.

Results

One-hundred and fifty six patients with 335 brain metastasis treated with SF-SRS (n = 222 lesions) or HF-SRS (n = 113 lesions) were included. Prior whole brain radiation was given in 33% (n = 74) and 34% (n = 38) of lesions treated with SF-SRS and HF-SRS, respectively (p = 0.30). After a median follow up time of 12 months in each cohort, the adjusted 1-year rate of local control and incidence of radiation necrosis was 91% (95% CI 86–96%) and 85% (95% CI 75–95%) (p = 0.26) and 10% (95% CI 5–15%) and 7% (95% CI 0.1–14%) (p = 0.73) for SF-SRS and HF-SRS, respectively. For lesions > 2 cm, the adjusted 1 year local control was 97% (95% CI 84–100%) for SF-SRS and 64% (95% CI 43–85%) for HF-SRS (p = 0.06). On multivariate analysis, SRS fractionation was not associated with local control and only size ≤2 cm was associated with a decreased risk of developing radiation necrosis (HR 0.21; 95% CI 0.07–0.58, p < 0.01). For HF-SRS, 1 year local control was 100% for lesions treated with a BED₁₀ ≥ 50 compared to 77% (95% CI 65–88%) for lesions that received a BED₁₀ < 50 (p = 0.09).

Conclusions

In this comparison study of dose fractionation for the treatment of brain metastases, there was no difference in local control or radiation necrosis between HF-SRS and SF-SRS. For HF-SRS, a BED₁₀ ≥ 50 may improve local control.

Pembrolizumab and cabozantinib in recurrent metastatic head and neck squamous cell carcinoma: a phase 2 trial

Anti-programmed cell death protein 1 (PD-1) therapy is a standard of care in recurrent metastatic head and neck squamous cell carcinoma (RMHNSCC). Vascular endothelial growth factor inhibitors, including tyrosine kinase inhibitors, have immunomodulatory properties and have offered promising results when combined with anti-PD-1 agents. We conducted a phase 2, multicenter, single-arm trial of pembrolizumab and cabozantinib in patients with RMHNSCC who had Response Evaluation Criteria in Solid Tumors v.1.1 measurable disease and no contraindications to either agent. We assessed the primary end points of tolerability and overall response rate to the combination with secondary end points of progression-free survival and overall survival and performed correlative studies with PDL-1 and combined positive score, CD8+ T cell infiltration and tumor mutational burden. A total of 50 patients were screened and 36 were enrolled with 33 evaluable for response. The primary end point was met, with 17 out of 33 patients having a partial response (52%) and 13 (39%) stable disease with an overall clinical benefit rate of 91%. Median and 1-year overall survival were 22.3 months (95% confidence interval (CI) = 11.7-32.9) and 68.4% (95% CI = 45.1%-83.5%), respectively. Median and 1-year progression-free survival were 14.6 months (95% CI = 8.2-19.6) and 54% (95% CI = 31.5%-72%), respectively. Grade 3 or higher treatment-related adverse events included increased aspartate aminotransferase (n = 2, 5.6%). In 16 patients (44.4%), the dose of cabozantinib was reduced to 20 mg daily. The overall response rate correlated positively with baseline CD8+ T cell infiltration. There was no observed correlation between tumor mutational burden and clinical outcome. Pembrolizumab and cabozantinib were well tolerated and showed promising clinical activity in patients with RMHNSCC. Further investigation of similar combinations are needed in RMHNSCC. The trial is registered at ClinicalTrials.gov under registration no. NCT03468218 .

Immune checkpoint inhibition in patients treated with stereotactic radiation for brain metastases

Purpose

Stereotactic radiation therapy (SRT) and immune checkpoint inhibitors (ICI) may act synergistically to improve treatment outcomes but may also increase the risk of symptomatic radiation necrosis (RN). The objective of this study was to compare outcomes for patients undergoing SRT with and without concurrent ICI.

Methods and materials

Patients treated for BMs with single or multi-fraction SRT were retrospectively reviewed. Concurrent ICI with SRT (SRT-ICI) was defined as administration within 3 months of SRT. Local control (LC), radiation necrosis (RN) risk and distant brain failure (DBF) were estimated by the Kaplan-Meier method and compared between groups using the log-rank test. Wilcoxon rank sum and Chi-square tests were used to compare covariates. Multivariate cox regression analysis (MVA) was performed.

Results

One hundred seventy-nine patients treated with SRT for 385 brain lesions were included; 36 patients with 99 lesions received SRT-ICI. Median follow up was 10.3 months (SRT alone) and 7.7 months (SRT- ICI) (p = 0.08). Lesions treated with SRT-ICI were more commonly squamous histology (17% vs 8%) melanoma (20% vs 2%) or renal cell carcinoma (8% vs 6%), (p < 0.001). Non-small cell lung cancer (NSCLC) compromised 60% of patients receiving ICI (n = 59). Lesions treated with SRT-ICI had significantly improved 1-year local control compared to SRT alone (98 and 89.5%, respectively (p = 0.0078). On subset analysis of NSCLC patients alone, ICI was also associated with improved 1 year local control (100% vs. 90.1%) (p = 0.018). On MVA, only tumor size ≤2 cm was significantly associated with LC (HR 0.38, p = 0.02), whereas the HR for concurrent ICI with SRS was 0.26 (p = 0.08). One year DBF (41% vs. 53%; p = 0.21), OS (58% vs. 56%; p = 0.79) and RN incidence (7% vs. 4%; p = 0.25) were similar for SRT alone versus SRT-ICI, for the population as a whole and those patients with NSCLC.

Conclusion

These results suggest SRT-ICI may improve local control of brain metastases and is not associated with an increased risk of symptomatic radiation necrosis in a cohort of predominantly NSCLC patients. Larger, prospective studies are necessary to validate these findings and better elucidate the impact of SRT-ICI on other disease outcomes.

Spatially Fractionated Radiotherapy (GRID) Prior to Standard Neoadjuvant Conventionally Fractionated Radiotherapy for Bulky, High-Risk Soft Tissue and Osteosarcomas: Feasibility, Safety, and Promising Pathologic Response Rates

Spatially fractionated radiotherapy (GRID) has been utilized primarily in the palliative and definitive treatment of bulky tumors. Delivered in the modern era primarily with megavoltage photon therapy, this technique offers the promise of safe dose escalation with potential immunogenic, bystander and microvasculature effects that can augment a conventionally fractionated course of radiotherapy. At the University of Maryland, an institutional standard has arisen to incorporate a single fraction of GRID radiation in large (>8 cm), high-risk soft tissue and osteosarcomas prior to a standard fractionated course. Herein, we report on the excellent pathologic responses and apparent safety of this regimen in 26 consecutive patients.

Reirradiation for locoregionally recurrent non-small cell lung cancer

Locoregional failure in non-small cell lung cancer (NSCLC) remains high, and the management for recurrent disease in the setting of prior radiotherapy is difficult. Retreatment options such as surgery or systemic therapy are typically limited or frequently result in suboptimal outcomes. Reirradiation (reRT) of thoracic malignancies may be an optimal strategy for providing definitive local control and offering a new chance of cure. Yet, retreatment with radiation therapy can be challenging for fear of excessive toxicities and the inability to safely deliver definitive (≥60 Gy) doses of reRT. However, with recent improvements in radiation delivery techniques and image-guidance, dose-escalation with reRT is possible and outcomes are encouraging. Here, we present a review of various radiation techniques, clinical outcomes and associated toxicities in patients with locoregionally recurrent NSCLC treated primarily with reRT.

Combining immunotherapy with radiation therapy in thoracic oncology

Thoracic malignancies comprise some of the most common and deadly cancers. Immunotherapies have been proven to improve survival outcomes for patients with advanced non-small cell lung cancer (NSCLC) and show great potential for patients with other thoracic malignancies. Radiation therapy (RT), an established and effective treatment for thoracic cancers, has acted synergistically with immunotherapies in preclinical studies. Ongoing clinical trials are exploring the clinical benefits of combining RT with immunotherapies and the optimal manner in which to deliver these complementary treatments.

Multiple Computed Tomography Robust Optimization to Account for Random Anatomic Density Variations During Intensity Modulated Proton Therapy

Purpose

To propose a method of optimizing intensity modulated proton therapy (IMPT) plans robust against dosimetric degradation caused by random anatomic variations during treatment.

Methods and Materials

Fifteen patients with prostate cancer treated with IMPT to the pelvic targets were nonrandomly selected. On the repeated quality assurance computed tomography (QACTs) for some patients, bowel density changes were observed and caused dose degradation because the treated plans were not robustly optimized (non-RO). To mitigate this effect, we developed a robust planning method based on 3 CT images, including the native planning CT and its 2 copies, with the bowel structures being assigned to air and tissue, respectively. The RO settings included 5 mm setup uncertainty and 3.5% range uncertainty on 3 CTs. This method is called pseudomultiple-CT RO (pMCT-RO). Plans were also generated using RO on the native CT only, with the same setup and range uncertainties. This method is referred to as single-CT RO (SCT-RO). Doses on the QACTs and the nominal planning CT were compared for the 3 planning methods.

Results

All 3 plan methods provided sufficient clinical target volumes D95% and V95% on the QACTs. For pMCT-RO plans, the normal tissue D_max on QACTs of all patients was at maximum 109.1%, compared with 144.4% and 116.9% for non-RO and SCT-RO plans, respectively. On the nominal plans, the rectum and bladder doses were similar among all 3 plans; however, the volume of normal tissue (excluding the rectum and bladder) receiving the prescription dose or higher is substantially reduced in either pMCT-RO plans or SCT-RO plans, compared with the non-RO plans.

Conclusions

We developed a robust optimization method to further mitigate undesired dose heterogeneity caused by random anatomic changes in pelvic IMPT treatment. This method does not require additional patient CT scans. The pMCT-RO planning method has been implemented clinically since 2017 in our center.

Tumor subtype and other prognostic factors in breast cancer patients with brain metastases: The updated graded prognostic assessment (Breast-GPA)

1079

Background: Brain metastases (BM) are a common and fatal complication of breast cancer but survival varies widely based on various prognostic factors (PF). Hence, patient counseling and therapeutic decisions should be individualized. We previously published a prognostic index (Breast GPA) based on cohort A (1985-2007, n = 642), updated it with tumor subtype in cohort B (1993-2010, n = 400) and are now updating it with a larger contemporary cohort (C). Methods: A multi-institutional (19) multi-national (3) retrospective database of 2473 breast cancer patients with BM diagnosed from 1/1/2006-12/31/2017 was created and compared to our prior cohorts. Demographic, clinical, molecular factors, tumor subtype and treatment were correlated with survival. Kaplan-Meier survival estimates were calculated and compared with log-rank tests. Results: The median survival (MS) for cohorts A, B and C improved over time [12, 14 and 16 mo, respectively ( < 0.01)] despite the subtype distribution becoming less favorable: Luminal B (ER/PR/HER2+) decreased from 26% to 21%; HER2 (HER2+/ER/PR-) decreased from 31% to 17%, Luminal A (ER/PR+/HER2-) increased from 20% to 31%; Basal (ER/PR/HER2-) was unchanged at 24%.MS by subtype improved from 21 to 27 mo in Luminal B, 18 to 25 mo in HER2, 10 to 14 mo in Luminal A and 6 to 9 mo in Basal tumors. The number of BM was 1 in 35%, ≤4 in 67% and > 10 in 18%. PF significant for survival were tumor subtype, age, KPS, number of BM and extracranial metastases (ECM) (all < 0.01). Surprisingly, Hispanic women (7%) showed improved survival (p < 0.01). BRCA1 was mutated in 57/533 (11%) and those patients showed a trend (0.16) toward improved survival. Treatment patterns have changed: the use of whole brain radiation therapy decreased from 71% to 67% to 47% in cohorts A, B and C, respectively. Conclusions: Despite the shift to less favorable tumor subtypes, MS has improvedbut varies widely by diagnosis-specific PF. Compared to prior cohorts, number of BM and ECM were identified as new PF. Ethnic, genetic and treatment differences between the eras are apparent. The updated Breast GPA, based on these data, and the correlation between BRCA1 and tumor subtype will be presented.

Downstream Effect of a Proton Treatment Center on an Academic Medical Center

PURPOSE

To quantify the effects of opening a proton center (PC) on an academic medical center (AMC)/radiation oncology department.

METHODS AND MATERIALS

Radiation treatment volume and relative value units from fiscal year 2015 (FY15) to FY17 were retrospectively analyzed at the AMC and 2 community-based centers. To quantify new patient referrals to the AMC, we reviewed the electronic medical record for all patients seen at the PC since consults were initiated in November 2015 (n = 1173). Patients were excluded if the date of entry into the AMC electronic medical record predated their PC consultation. Hospital resource use and professional and technical charges were obtained for these patients. Academic growth, philanthropy, and resident education were evaluated based on grant submissions, clinical trial enrollment, philanthropy, and pediatric case exposure, respectively, from PC opening through FY17.

RESULTS

From FY15 to FY17, radiation fractions at the AMC and the 2 community sites decreased by 14% (95% confidence interval [CI], 12%-16%, P < .001) and increased by 19% (95% CI, 16%-23%, P < .001) and 2% (95% CI, -1.1 to 4.3%, P = NS), respectively; the number of new starts decreased by 3% (95% CI, -13% to 7%, P = NS) and 2% (95% CI, -20% to 16%, P = NS) and increased by 13% (95% CI -2% to 27%, P = NS), respectively. At the AMC, technical and professional relative value units decreased by 5% and 14%, respectively. The PC made 561 external referrals to the AMC, which resulted in $2.38 million technical and $2.13 million professional charges at the AMC. Fifteen grant submissions ($12.83 million) resulted in 6 awards ($3.26 million). Twenty-two clinical trials involving proton therapy were opened, on which a total of 5% (n = 54) of patients enrolled during calendar years 2017 and 2018. The PC was involved in gift donations of $1.6 million. There was a nonsignificant 37% increase in number of pediatric cases.

CONCLUSIONS

Despite a slight decline in AMC photon patient volumes and relative value units, a positive downstream effect was associated with the addition of a PC, which benefited the AMC.

Effect of COVID-19 on Gynecologic Oncology Care: A Survey of Practicing Gynecologic Radiation Oncologists in the United States

Purpose

The COVID-19 pandemic has placed demands and limitations on the delivery of health care. We sought to assess the effect of COVID-19 on the delivery of gynecologic oncologic care from the perspective of practicing radiation oncologists in the United States.

Methods and Materials

An anonymous online survey was created and distributed to preidentified radiation oncologists in the United States with clinical expertise in the management of gynecologic patients. The survey consisted of demographic questions followed by directed questions to assess specific patterns of care related to the COVID-19 pandemic.

Results

A total of 47 of 96 invited radiation oncologists responded to the survey for a response rate of 49%. Fifty-six percent of respondents reported an increase in locally advanced cervical cancer with no similar increase for endometrial, vulvar, or vaginal patients. Most respondents (66%) reported a pause in surgical management, with a duration of 1 to 3 months being most common (61%). There was a reported increased use of shorter brachytherapy regimens during the pandemic. Most providers (61%) reported caring for at least 1 patient with a positive COVID-19 test. A pause or delay in treatment due to COVID-19 positivity was reported by 45% of respondents, with 55% reporting that patients chose to delay their own care because of COVID-19-related concerns. Total treatment times >8 weeks for patients with cervical cancer were observed by 33% of respondents, but occurred in >25% of patients.

Conclusions

Data from this prospectively collected anonymous survey of practice patterns among radiation oncologists reveal that the COVID-19 pandemic resulted in delays initiating care, truncated brachytherapy treatment courses, and a reported increase in locally advanced cervical cancer cases at presentation. These data can be used as a means of self-assessment to ensure appropriate decision making for gynecologic patients during the endemic phase of COVID-19.

Associations Between Social Determinants of Health and Psychoneurologic Symptom Clusters in Women With Gynecologic Cancers: A Longitudinal Study

OBJECTIVES

To evaluate the associations between social determinants of health (SDOH) and psychoneurologic symptom (PNS) clusters in women with gynecologic cancers during cancer treatment.

SAMPLE & SETTING

67 women with gynecologic cancers who received radiation therapy were assessed at baseline, six to eight weeks after treatment, and six months after treatment at oncology clinics in Georgia.

METHODS & VARIABLES

Fatigue, pain, sleep disturbances, cognitive impairment, and depressive symptoms were measured to determine a PNS cluster score. Associations between SDOH and PNS cluster scores were assessed using mixed-effect models.

RESULTS

Larger mean PNS cluster scores were reported in individuals with less education, lower income, and unemployment, as well as in those living in more disadvantaged neighborhoods.

IMPLICATIONS FOR NURSING

Individual- and community-level SDOH and their interactions were associated with more PNS clusters. Studying SDOH at multiple levels depicts how various social disadvantages can exacerbate poor health outcomes.

AB, McCook-Veal AA, Switchenko JM, Cole TE, Khanna N, Han CH, Gordon AN, Starbuck KD, Remick JS. Incidence and predictors of toxicity in the management of vulvar squamous cell carcinoma treated with radiation therapy

Purpose/Objective

Given the rarity of vulvar cancer, data on the incidence of acute and late severe toxicity and patients' symptom burden from radiotherapy (RT) are lacking.

Materials/Methods

This multi-center, single-institution study included patients with vulvar squamous cell carcinoma treated with curative intent RT between 2009 and 2020. Treatment-related acute and late grade ≥ 3 toxicities and late patient subjective symptoms (PSS) were recorded.

Results

Forty-two patients with predominantly stage III/IV disease (n = 25, 59.5 %) were treated with either definitive (n = 25, 59.5 %) or adjuvant (n = 17, 40.5 %) external beam RT to a median dose of 64 Gy and 59.4 Gy, respectively. Five patients received a brachytherapy boost with a median total dose of 84.3 Gy in 2 Gy-equivalent dose (EQD2). Intensity-modulated RT was used in 37 (88.1 %) of patients, and 25 patients (59.5 %) received concurrent chemotherapy. Median follow-up was 27 months. Acute grade ≥ 3 toxicity occurred in 17 patients (40.5 %), including 13 (31.0 %) acute grade 3 skin events. No factors, including total RT dose (p = 0.951), were associated with acute skin toxicity. Eleven (27.5 %) patients developed late grade ≥ 3 toxicity events, including 10 (23.8 %) late grade ≥ 3 skin toxicity events. Patients with late grade ≥ 3 skin toxicity had a higher mean body-mass index (33.0 vs 28.2 kg/m²; p = 0.009). Common late PSS included vaginal pain (n = 15, 35.7 %), skin fibrosis (n = 10, 23.8 %), and requirement of long-term opiates (n = 12, 28.6 %).

Conclusion

RT for vulvar cancer is associated with considerable rates of severe acute and late toxicity and PSS burden. Larger studies are needed to identify risk factors, explore toxicity mitigation strategies, and assess patient-reported outcomes.

Intensity-Modulated Reirradiation Therapy With Nivolumab in Recurrent or Second Primary Head and Neck Squamous Cell Carcinoma: A Nonrandomized Controlled Trial

Importance

Intensity-modulated radiation therapy (IMRT) reirradiation of nonmetastatic recurrent or second primary head and neck squamous cell carcinoma (HNSCC) results in poor progression-free survival (PFS) and overall survival (OS).

Objective

To investigate the tolerability, PFS, OS, and patient-reported outcomes with nivolumab (approved standard of care for patients with HNSCC) during and after IMRT reirradiation.

Design, Setting, and Participants

In this multicenter nonrandomized phase 2 single-arm trial, the treatment outcomes of patients with recurrent or second primary HNSCC who satisfied recursive partitioning analysis class 1 and 2 definitions were evaluated. Between July 11, 2018, and August 12, 2021, 62 patients were consented and screened. Data were evaluated between June and December 2023.

Intervention

Sixty- to 66-Gy IMRT in 30 to 33 daily fractions over 6 to 6.5 weeks with nivolumab, 240 mg, intravenously 2 weeks prior and every 2 weeks for 5 cycles during IMRT, then nivolumab, 480 mg, intravenously every 4 weeks for a total nivolumab duration of 52 weeks.

Main Outcomes and Measures

The primary end point was PFS. Secondary end points included OS, incidence, and types of toxic effects, including long-term treatment-related toxic effects, patient-reported outcomes, and correlatives of tissue and blood biomarkers.

Results

A total of 62 patients were screened, and 51 were evaluable (median [range] age was 62 [56-67] years; 42 [82%] were male; 6 [12%] had p16+ disease; 38 [75%] had salvage surgery; and 36 [71%.] had neck dissection). With a median follow-up of 24.5 months (95% CI, 19.0-25.0), the estimated 1-year PFS was 61.7% (95% CI, 49.2%-77.4%), rejecting the null hypothesis of 1-year PFS rate of less than 43.8% with 1-arm log-rank test P = .002 within a 1-year timeframe. The most common treatment-related grade 3 or higher adverse event (6 [12%]) was lymphopenia with 2 patients (4%) and 1 patient each (2%) exhibiting colitis, diarrhea, myositis, nausea, mucositis, and myasthenia gravis. Functional Assessment of Cancer Therapy-General and Functional Assessment of Cancer Therapy-Head and Neck Questionnaire quality of life scores remained stable and consistent across all time points. A hypothesis-generating trend favoring worsening PFS and OS in patients with an increase in blood PD1+, KI67+, and CD4+ T cells was observed.

Conclusions and Relevance

This multicenter nonrandomized phase 2 trial of IMRT reirradiation therapy and nivolumab suggested a promising improvement in PFS over historical controls. The treatment was well tolerated and deserves further evaluation.

Trial Registration

ClinicalTrials.gov Identifier: NCT03521570.

Photon vs. Proton Radiotherapy in the Definitive Treatment of Nasopharyngeal Cancer: Single Institution Experience

PURPOSE/OBJECTIVE(S)

Definitive therapy for nasopharyngeal cancer includes chemotherapy and radiation (RT). Common toxicities such as xerostomia, mucositis, and hearing loss are correlated with the RT dose delivered to associated organs at risk. We hypothesized that compared to our historical experience with IMRT, the implementation of proton therapy (PT) would reduce radiation dose to organs at risks without compromising oncologic outcomes.

MATERIALS/METHODS

A retrospective review of all non-metastatic stage II-IV nasopharyngeal carcinoma (SCC, lymphoepithelioma, undifferentiated carcinomas) treated with definitive therapy at our institution from 2012-2022. Disease parameters and the mean dose to organs at risk were evaluated. Statistical comparison was made with the chi square test for categorical and Wilcoxon rank sum test for continuous variables. The Kaplan-Meier method was used to estimate overall survival (OS) and progression-free survival (PFS), using a log-rank test to compare IMRT and PT. PFS was defined as the time from the start of treatment to the first of either disease progression, relapse or death from any cause. PT was delivered with pencil-beam scanning in all patients. IMRT included multi-field treatment and volumetric-modulated arc therapy.

RESULTS

A total of 80 patients were included in analyses: 48 treated with IMRT and 32 with PT. Comparing IMRT to PT cohorts, there was no difference in the median age of patients (51 vs 55 years, p = 0.73), nor the distribution by T stage (p = 0.57) or N stage (p = 0.34) or in the percentage of patients with ECOG 2/3 performance status at presentation (p = 0.11). All but one patient received concurrent systemic therapy and there was no difference in the use of concurrent cisplatin between cohorts (83% vs 78%, p = 0.57). The most common non-cisplatin concurrent regimen was weekly carboplatin and paclitaxel. Induction chemotherapy was more commonly used in patients treated with PT (10.4% vs 25%, p = 0.04) while there was no difference in the use of adjuvant chemotherapy (10.4% vs 9.4%, p = 0.88). Among 42 cases initiating treatment since the opening of our proton center, 32 (76%) have received PT. Comparing IMRT and PT dosimetry, patients treated with PT received significantly lower mean dose to the better spared parotid gland (32.8 vs 25.7 Gy, p = 0.001), lesser spared parotid gland (35.5 vs 31.1 Gy, p = 0.047), better spared cochlea (31.5 vs 25.5 Gy, p = 0.004), lesser spared cochlea (41.8 vs 33.2 Gy, p = 0.004), larynx (44.5 vs 21.7 Gy, p<0.001), and oral cavity (42.6 vs 17.0 Gy, p<0.001). After a median follow-up time of 30 months (45 mos IMRT, 23 mos PT) the estimated 2-year PFS was 63.9% with IMRT and 90.3% with PT (p = 0.047). The estimate of 2-year overall survival was 86.8% with IMRT and 96.8% with PT (p = 0.17).

CONCLUSION

Comparing patients by radiation treatment modality, PT was associated with a statistically significant reduction in mean radiation dose to the parotid glands, cochlea, larynx, and oral cavity with excellent initial oncologic outcomes.

Ninety-day mortality following transoral robotic surgery or radiation at Commission on Cancer-accredited facilities

BACKGROUND

Postoperative mortality for oropharynx squamous cell carcinoma (OPSCC) with transoral robotic surgery (TORS) varies from 0.2% to 6.5% on trials; the real-world rate is unknown.

METHODS

NCDB study from 2010 to 2017 for patients with cT1-2N0-2M0 OPSCC with Charleson-Deyo score 0-1. Ninety-day mortality assessed from start and end of treatment at Commission on Cancer-accredited facilities.

RESULTS

3639 patients were treated with TORS and 1937 with radiotherapy. TORS cohort had more women and higher income, was younger, more often treated at academic centers, and more likely to have private insurance (all p < 0.05). Ninety-day mortality was 1.3% with TORS and 0.7% or 1.4% from start or end of radiotherapy, respectively. From end of therapy, there was no significant difference on MVA between treatment modality.

CONCLUSIONS

There is minimal difference between 90-day mortality in patients treated with TORS or radiotherapy for early-stage OPSCC. While overall rates are low, for patients with expectation of cure, work is needed to identify optimal treatment.

Patterns of Undertreatment and Overtreatment in Adjuvant Radiotherapy for Early-Stage Endometrial Cancer Based on Molecular Classification

The quality improvement study examines the use of risk-adaptive adjuvant radiotherapy in women with non–mismatch repair deficiency endometrial cancer.

Pembrolizumab and Cabozantinib in Recurrent and/or Metastatic Head and Neck Squamous Cell Carcinoma: Long-term Survival Update with a Biomarker Analysis

PURPOSE

Anti-programmed cell death protein 1 (PD-1) therapy is a standard of care in recurrent and/or metastatic head and neck squamous cell carcinoma (RMHNSCC). Vascular endothelial growth factor receptor tyrosine kinase inhibitors (VEGFR-TKI) have immunomodulatory properties and improve clinical outcomes in combination with anti-PD-1 therapy in different malignancies. We report the long-term efficacy and safety of pembrolizumab and cabozantinib in patients with RMHNSCC and include a correlative biomarker analysis.

PATIENTS AND METHODS

This open-label, single-arm, multicenter, phase 2 study screened 50 patients with RMHNSCC, of whom 36 received pembrolizumab and cabozantinib. The primary endpoint was overall response rate (ORR), safety, and tolerability. Secondary endpoints included progression-free survival (PFS), overall survival (OS), and correlative studies of tissue and blood. We report the long-term PFS, OS, and safety of treated patients and describe correlative biomarkers evaluating p-MET expression and tumor immune microenvironment (TIME) using multiplex immunohistochemistry.

RESULTS

With median follow-up of 22.4 months, the median PFS was 12.8 months with a 2-year PFS of 32.6% (95% CI, 18.8%-56.3%) and the median OS was 27.7 months with a 2-year OS of 54.7% [95% confidence interval (CI), 38.9%-76.8%]. The median duration of response was 12.6 months with a 2-year rate of 38.5% (95% CI, 30.8%-81.8%). Long-term treatment-related adverse events included manageable hypothyroidism (5.5%) and grade 1 elevated aspartate aminotransferase and alanine aminotransferase (2.8%). Baseline tumor p-MET expression correlated with ORR (P = 0.0055). Higher density of CD8+, CD103+, and CSF1-R+ cells at baseline correlated with improved OS [hazard ratio (HR) = 5.27, P = 0.030; HR = 8.79, P = 0.017; HR = 6.87, P = 0.040, respectively].

CONCLUSIONS

Pembrolizumab and cabozantinib provided prolonged encouraging long-term disease control and survival with a maintained favorable safety profile. The prognostic significance of higher density of CD8+, CD103+, and CSF1-R+ cells in TIME deserve further evaluation in similar clinical settings.

Insurance Authorization and Access to Proton Therapy for Patients With Head and Neck Cancers

PURPOSE

We evaluated our institutional experience to assess potential racial inequities in insurance coverage for proton therapy in patients with head and neck (HN) cancer.

METHODS AND MATERIALS

We examined the demographics of 1519 patients with HN cancer seen in consultation at our HN multidisciplinary clinic (HN MDC) and 805 patients for whom a proton insurance authorization was sought (PAS) from January 2020 to June 2022. The prospects for proton therapy insurance authorization were prospectively noted based on each patient's ICD-10 (International Classification of Diseases, 10th Revision) diagnosis code and their specific insurance plan. Proton-unfavorable (PU) insurance were those plans whose policy describes proton beam therapy as "experimental" or "not medically necessary" for the given diagnosis.

RESULTS

For patients seen in our HN MDC, Black, Indigenous, and people of color (BIPOC) were significantly more likely to have PU insurance than non-Hispanic White (NHW) patients (24.9% vs 18.4%, P = .005). In multivariable analysis including race, average income of residence ZIP code, and Medicare eligibility age, BIPOC patients had an odds ratio of 1.25 for PU insurance (P = .041). In the PAS cohort, while there was no difference in the percentage of patients receiving insurance approval for proton therapy between NHW and BIPOC populations (88% vs 88.2%, P = .80), for patients with PU insurance, the median time to determination was significantly longer (median, 15.5 days), and the median time to start any radiation of any modality was longer (46 vs 35 days, P = .08). Compared with NHW patients, the median time from consultation to start of radiation therapy was longer for BIPOC patients (37 vs 43 days, P = .01).

CONCLUSIONS

BIPOC patients were significantly more likely to have insurance plans unfavorable to proton therapy coverage. These PU insurance plans were associated with a longer median time to determination, a lower approval rate for proton therapy, and a longer time to start radiation of any modality.