Incorporating radiation with anti-CD19 chimeric antigen receptor T-cell therapy for relapsed/refractory non-Hodgkin lymphoma: A multicenter consensus approach.

Anti-CD19 chimeric antigen receptor T-cell therapy (CART) has revolutionized the outcomes of relapsed and/or refractory B-cell non-Hodgkin lymphoma. However, CART is still limited by its availability, toxicity, and response durability. Not all patients make it to the CART infusion phase due to disease progression. Among those who receive CART, a significant number of patients experience life-threatening cytokine release syndrome toxicity, and less than half maintain a durable response with the majority relapsing in pre-existing sites of disease present pre-CART. Radiation therapy stands as a promising peri-CART and salvage treatment that can improve the outcomes of these patients. Evidence suggests that bridging radiotherapy prior to CART controls the disease during the manufacturing period, augments response rates and local control, cytoreduces/debulks the disease and decreases the severity of cytokine release syndrome, and may prolong disease-free intervals and survival especially in patients with bulky disease. Consolidative radiotherapy for residual post-CART disease alters the pattern of relapse and improves local recurrence-free and progression-free survivals. Salvage radiotherapy for relapsed post-CART disease has favorable survival outcomes when delivered comprehensively for patients with limited relapsed disease and palliates symptoms for patients with diffuse relapsed disease. The biology of the disease during the peri-CART period is poorly understood, and further studies investigating the optimal timing and dosing of radiation therapy (RT) are needed. In this review, we tackle the most significant challenges of CART, review and propose how RT can help mitigate these challenges, and provide The Mayo Clinic experts' approach on incorporating RT with CART.

Consolidative radiotherapy for residual fluorodeoxyglucose activity on day +30 post CAR T-cell therapy in non-Hodgkin lymphoma.

Majority of non-Hodgkin lymphoma (NHL) patients who achieve partial response (PR) or stable disease (SD) to CAR T-cell therapy (CAR T) on day +30 progress and only 30% achieve spontaneous complete response (CR). This study is the first to evaluate the role of consolidative radiotherapy (cRT) for residual fluorodeoxyglucose (FDG) activity on day +30 post- CAR T in NHL. We retrospectively reviewed 61 patients with NHL who received CAR T and achieved PR or SD on day +30. Progression-free survival (PFS), overall survival (OS), and local relapse-free survival (LRFS) were assessed from CAR T infusion. cRT was defined as comprehensive - treated all FDG-avid sites - or focal. Following day +30 positron emission tomography scan, 45 patients were observed and 16 received cRT. Fifteen (33%) observed patients achieved spontaneous CR, and 27 (60%) progressed with all relapses involving initial sites of residual FDG activity. Ten (63%) cRT patients achieved CR, and four (25%) progressed with no relapses in the irradiated sites. The 2-year LRFS was 100% in the cRT sites and 31% in the observed sites (P<0.001). The 2-year PFS was 73% and 37% (P=0.025) and the 2-year OS was 78% and 43% (P=0.12) in the cRT and observation groups, respectively. Patients receiving comprehensive cRT (n=13) had superior 2- year PFS (83% vs. 37%; P=0.008) and 2-year OS (86% vs. 43%; P=0.047) compared to observed or focal cRT patients (n=48). NHL patients with residual FDG activity following CAR T are at high risk of local progression. cRT for residual FDG activity on day +30 post-CAR T appears to alter the pattern of relapse and improve LRFS and PFS.

Attitudes and Perception of the REFLECT Communication Curriculum for Clinical Oncology Graduate Medical Education.

Communication and interpersonal skills are essential components of oncology patient care. The REFLECT (Respect, Empathy, Facilitate Effective Communication, Listen, Elicit Information, Compassion, and Teach Others) curriculum is a novel framework to improve and refine physician/patient interactions for oncology graduate medical trainees. We seek to evaluate the attitudes and perceptions of the REFLECT communication curriculum among oncology trainees. Seven-question and 8-question Likert scale surveys (1 = not beneficial and 5 = beneficial) were distributed to resident/fellow participants and faculty mentors, respectively. Questions asked trainees and faculty about their perceptions of improvement in communication, handling of stressful situations, the value of the curriculum, and overall impression of the curriculum. Descriptive statistics determined the survey's baseline characteristics and response rates. Kruskal-Wallis rank sum tests were used to compare the distribution of continuous variables. Thirteen resident/fellow participants completed the participant survey. Six (43.6%) Radiation Oncology trainees and 7 (58.3%) Hematology/Oncology fellows completed the trainee survey. Eight (88.9%) Radiation Oncologists and 1 (11.1%) Medical Oncologist completed the observer survey. Faculty and trainees generally felt that the curriculum increased communication skills. Faculty responded more favorably to the program's impact on communication skills (median 5.0 vs. 4.0, p = 0.008). Faculty were more assertive about the curriculum's capabilities to improve a learner's ability to handle stressful situations (median 5.0 vs. 4.0, p = 0.003). Additionally, faculty had a more favorable overall impression of the REFLECT curriculum than the residents/fellows (median 5.0 vs. 4.0, p < 0.001). Radiation Oncology residents felt more strongly that the curriculum enhanced their ability to handle stressful topics, compared to Heme/Onc fellows (median 4.5 vs. 3.0, range 1-5, p = 0.379). Radiation Oncology trainees felt more consistently that the workshops improved their communication skills, compared to Heme/Onc fellows (median 4.5 vs. 3.5, range 1-5, p = 0.410). The overall impression between Rad Onc resident and Heme/Onc fellows was similar (median 4.0, p = 0.586). Conclusions: Overall, the REFLECT curriculum enhanced communication skills of trainees. Oncology trainees and faculty physicians feel that the curriculum was beneficial. As interactive skills and communication is critical to build positive interactions, further work is needed to improve the REFLECT curriculum.

How to Sequence Therapies in Mycosis Fungoides.

OPINION STATEMENT: Choice of therapy in mycosis fungoides is based on both patient- and lymphoma-specific factors, such as disease characteristics, comorbidities, symptoms and effect on quality of life, potential associated toxicities of therapy, response and tolerance to prior lines of therapy, and convenience and practicality. Generally, we sequence therapies from least toxic, targeted, nonimmunosuppressive to more toxic, immunosuppressive and from single agent to multiple agents, as necessary. If more toxic, immunosuppressive agents are required to alleviate disease burden or symptoms, we generally use them just long enough to control the disease, then transition to a maintenance regimen with less toxic, less immunosuppressive agents.

Beam angle comparison for distal esophageal carcinoma patients treated with intensity-modulated proton therapy.

PURPOSE: To compare the dosimetric performances of intensity-modulated proton therapy (IMPT) plans generated with two different beam angle configurations (the Right-Left oblique posterior beams and the Superior-Inferior oblique posterior beams) for the treatment of distal esophageal carcinoma in the presence of uncertainties and interplay effect. METHODS AND MATERIALS: Twenty patients' IMPT plans were retrospectively selected, with 10 patients treated with the R-L oblique posterior beams (Group R-L) and the other 10 patients treated with the S-I oblique posterior beams (Group S-I). Patients in both groups were matched by their clinical target volumes (CTVs-high and low dose levels) and respiratory motion amplitudes. Dose-volume-histogram (DVH) indices were used to assess plan quality. DVH bandwidth was calculated to evaluate plan robustness. Interplay effect was quantified using four-dimensional (4D) dynamic dose calculation with random respiratory starting phase of each fraction. Normal tissue complication probability (NTCP) for heart, liver, and lung was calculated, respectively, to estimate the clinical outcomes. Wilcoxon signed-rank test was used for statistical comparison between the two groups. RESULTS: Compared with plans in Group R-L, plans in Group S-I resulted in significantly lower liver Dmean and lung V30Gy[RBE] with slightly higher but clinically acceptable spinal cord Dmax . Similar plan robustness was observed between the two groups. When interplay effect was considered, plans in Group S-I performed statistically better for heart Dmean and V30Gy[RBE] , lung Dmean and V5Gy[RBE] , and liver Dmean , with slightly increased but clinically acceptable spinal cord Dmax . NTCP for liver was significantly better in Group S-I. CONCLUSIONS: IMPT plans in Group S-I have better sparing of liver, heart, and lungs at the slight cost of spinal cord maximum dose protection, and are more interplay-effect resilient compared to IMPT plans in Group R-L. Our study supports the routine use of the S-I oblique posterior beams for the treatments of distal esophageal carcinoma.

Dosimetric comparison of distal esophageal carcinoma plans for patients treated with small-spot intensity-modulated proton versus volumetric-modulated arc therapies.

BACKGROUND: Esophageal carcinoma is the eighth most common cancer in the world. Volumetric-modulated arc therapy (VMAT) is widely used to treat distal esophageal carcinoma due to high conformality to the target and good sparing of organs at risk (OAR). It is not clear if small-spot intensity-modulated proton therapy (IMPT) demonstrates a dosimetric advantage over VMAT. In this study, we compared dosimetric performance of VMAT and small-spot IMPT for distal esophageal carcinoma in terms of plan quality, plan robustness, and interplay effects. METHODS: 35 distal esophageal carcinoma patients were retrospectively reviewed; 19 patients received small-spot IMPT and the remaining 16 of them received VMAT. Both plans were generated by delivering prescription doses to clinical target volumes (CTVs) on phase-averaged 4D-CT's. The dose-volume-histogram (DVH) band method was used to quantify plan robustness. Software was developed to evaluate interplay effects with randomized starting phases for each field per fraction. DVH indices were compared using Wilcoxon rank-sum test. For fair comparison, all the treatment plans were normalized to have the same CTVhigh D95% in the nominal scenario relative to the prescription dose. RESULTS: In the nominal scenario, small-spot IMPT delivered statistically significantly lower liver Dmean and V30Gy[RBE] , lung Dmean , heart Dmean compared with VMAT. CTVhigh dose homogeneity and protection of other OARs were comparable between the two treatments. In terms of plan robustness, the IMPT and VMAT plans were comparable for kidney V18Gy[RBE] , liver V30Gy[RBE] , stomach V45Gy[RBE] , lung Dmean , V5Gy[RBE] , and V20Gy[RBE] , cord Dmax and D 0.03 c m 3 , liver Dmean , heart V20Gy[RBE] , and V30Gy[RBE] , but IMPT was significantly worse for CTVhigh D95% , D 2 c m 3 , and D5% -D95% , CTVlow D95% , heart Dmean , and V40Gy[RBE] , requiring careful and experienced adjustments during the planning process and robustness considerations. The small-spot IMPT plans still met the standard clinical requirements after interplay effects were considered. CONCLUSIONS: Small-spot IMPT decreases doses to heart, liver, and total lung compared to VMAT as well as achieves clinically acceptable plan robustness. Our study supports the use of small-spot IMPT for the treatment of distal esophageal carcinoma.

Small-spot intensity-modulated proton therapy and volumetric-modulated arc therapies for patients with locally advanced non-small-cell lung cancer: A dosimetric comparative study.

PURPOSE: To compare dosimetric performance of volumetric-modulated arc therapy (VMAT) and small-spot intensity-modulated proton therapy for stage III non-small-cell lung cancer (NSCLC). METHODS AND MATERIALS: A total of 24 NSCLC patients were retrospectively reviewed; 12 patients received intensity-modulated proton therapy (IMPT) and the remaining 12 received VMAT. Both plans were generated by delivering prescription doses to clinical target volumes (CTV) on averaged 4D-CTs. The dose-volume-histograms (DVH) band method was used to quantify plan robustness. Software was developed to evaluate interplay effects with randomized starting phases of each field per fraction. DVH indices were compared using Wilcoxon rank sum test. RESULTS: Compared with VMAT, IMPT delivered significantly lower cord Dmax , heart Dmean , and lung V5 Gy[ RBE ] with comparable CTV dose homogeneity, and protection of other OARs. In terms of plan robustness, the IMPT plans were statistically better than VMAT plans in heart Dmean , but were statistically worse in CTV dose coverage, cord Dmax , lung Dmean , and V5 Gy[ RBE ] . Other DVH indices were comparable. The IMPT plans still met the standard clinical requirements with interplay effects considered. CONCLUSIONS: Small-spot IMPT improves cord, heart, and lung sparing compared to VMAT and achieves clinically acceptable plan robustness at least for the patients included in this study with motion amplitude less than 11 mm. Our study supports the usage of IMPT to treat some lung cancer patients.

Implementation of the REFLECT Communication Curriculum for Clinical Oncology Graduate Medical Education.

Background: Communication and interpersonal skills are essential medical components of oncology patient care. Patients and families rely on physicians for treatment, expertise, guidance, hope, meaning, and compassion throughout a life-threatening illness. A provider's inability to empathize with patients is linked to physician-related fatigue and burnout. Because oncology training programs focus on teaching evidence-based medicine and clinical acumen, little time may be dedicated to professional development and acquisition of interactive skills. Traditional communication courses typically include two components: formal, knowledge-based learning skills, which are gained from didactic lectures, and role-playing, which usually occurs in small groups. We report the implementation of a novel longitudinal communication curriculum for trainees in Oncology. Materials and Methods: At a single-center institution, an innovative communication curriculum titled "REFLECT" (Respect, Empathy, Facilitate Effective Communication, Listen, Elicit Information, Compassion, and Teach Others) was implemented for radiation oncology residents and medical oncology fellows to improve and refine physician/patient interactions. All oncology specialty residents and fellows were eligible to participate in this communication curriculum. The curriculum emphasized a reflective process to guide trainees through challenging scenarios. Results: Since October 2018, this comprehensive course consisted of quarterly (four hour) workshops comprising assigned reading, knowledge assessments, didactic lectures, expert guest lecturers, standardized patient simulations, role-playing, patient/expert panels, coaching, reflective writing, and debriefing/feedback sessions. The curriculum provided longitudinal communication training integrated with the learners' daily physician/patient encounters rather than occasional isolated experiences. Fifteen workshops have been completed. Each focused on navigating challenging situations with patients, loved ones, or colleagues. Conclusions: Future directions of the curriculum will entail improving the communication skills of oncology trainees and gathering communication improvement data to assess the program's success formally.

Fine-Tuning Low-Dose Total Skin Electron Therapy for Optimal Management of Cutaneous T-Cell Lymphoma: A Comparative Analysis of Regimens.

Purpose: Low-dose total skin electron beam therapy (TSEBT) is a proven treatment for managing cutaneous T-cell lymphoma (CTCL) and Sezary syndrome with skin burden. We performed a retrospective comparison of response rates and time to progression for patients receiving low-dose TSEBT based on dose per fractionation, total dose, and stage. Methods and Materials: One hundred and ten patients with CTCL and Sezary syndrome were treated with 135 courses of low-dose (400-1500 cGy) TSEBT or subtotal skin electron therapy at multiple centers of a single institution between August 2003 and June 2023. Patients were stratified according to total dose, dose per fraction, and stage. Results: The median follow-up was 301 days (IQR, 141, 767). The median age at treatment was 69.9 years (range, 29.7-96.5). T-stage distribution was as follows: 3 (2.7%) T1, 74 (67.3%) T2, 16 (14.5%) T3, and 17 (15.5%) T4. American Joint Committee on Cancer eighth edition stage distribution was as follows: 3 (2.7%) IA, 53 (48.2%) IB, 3 (2.7%) IIA, 16 (14.5%) IIB, 8 (7.3%) IIIA, 19 (17.3%) IVA, and 8 (7.3%) IVB. There was no significant difference in disease distribution between patients treated with different fractionation schemes. The overall response rate was 89.6%. Forty-four courses (32.6%), 34 courses (25.2%), and 43 (31.9%) resulted in a complete, near-complete, and partial response, respectively. Fourteen courses (10.4%) resulted in no clinical response. For all patients, the median time to response was 43.0 days (IQR, 23.0-70). The median time to skin progression for all patients was 107.5 days (IQR, 67.8-233.5). Conclusions: This analysis demonstrated that CTCL patients treated with low-dose radiation therapy delivered over various fractionation schemes had similar overall response rates and median time to progression.

Tailoring Radiation Therapy for Patients With Limited Cutaneous T Cell Lymphoma: Preliminary Clinical Experience With Subtotal Skin Electron Therapy.

BACKGROUND/AIM: Total skin electron beam therapy (TSEBT) is an effective treatment for managing cutaneous T-cell lymphoma (CTCL), but may result in unnecessary toxicity. With the production of a custom rolling shield holding a configurable stack of plastic slats to block uninvolved skin, we implemented a program for subtotal skin electron beam therapy (STSEBT). We report our preliminary experience with STSEBT vs. TSEBT to manage CTCL. PATIENTS AND METHODS: A retrospective review of 32 CTCL patients who were treated at a single institution between February 28th, 2017, and May 25th, 2022, was completed. Of these cases, seven patients received STSEBT and 25 received TSEBT. RESULTS: Thirty-two patients underwent a course of STSEBT or TSEBT. The median follow-up was 465 days and the median age at diagnosis was 70.8 years. Stage distribution was as follows: one (3%) IA, 16 (50%) IB, 6 (19%) IIB, two (6%) IIIA, five (16%) IVA, and two (6%) IVB. The overall response rate was 96%. For patients receiving TSEBT (n=25), three (12%), 10 (40%), and 11 (44%) had a CR, NCR, and PR, respectively. For the patients receiving STSEBT, four (57.1%), three (42.9%), and zero (0%) had a CR, NCR, and PR, respectively. There was one patient (4%) with no response. Cumulative incidence of progressive skin disease requiring additional electron therapy at three months was 21.1% [IQR=8.6, 51.5%], 36.8% [IQR=20, 68%] at six months, and 57.9% [IQR=38.5, 87.1%] at one year. Low rates of toxicities were recorded. CONCLUSION: This analysis demonstrated that treatment of CTCL patients with low disease burden with STSEBT results in similar overall response and time to progression compared to treatment with TSEBT.

Reirradiation With Proton Therapy for Recurrent Malignancies of the Esophagus and Gastroesophageal Junction: Results of the Proton Collaborative Group Multi-Institutional Prospective Registry Trial.

Purpose: Treatment options for recurrent esophageal cancer (EC) previously treated with radiation therapy (RT) are limited. Reirradiation (reRT) with proton beam therapy (PBT) can offer lower toxicities by limiting doses to surrounding tissues. In this study, we present the first multi-institutional series reporting on toxicities and outcomes after reRT for locoregionally recurrent EC with PBT. Methods and Materials: Analysis of the prospective, multicenter, Proton Collaborative Group registry of patients with recurrent EC who had previously received photon-based RT and underwent PBT reRT was performed. Patient/tumor characteristics, treatment details, outcomes, and toxicities were collected. Local control (LC), distant metastasis-free survival (DMFS), and overall survival (OS) were estimated using the Kaplan-Meier method. Event time was determined from reRT start. Results: Between 2012 and 2020, 31 patients received reRT via uniform scanning/passive scattering (61.3%) or pencil beam scanning (38.7%) PBT at 7 institutions. Median prior RT, PBT reRT, and cumulative doses were 50.4 Gy (range, 37.5-110.4), 48.6 Gy (relative biological effectiveness) (25.2-72.1), and 99.9 Gy (79.1-182.5), respectively. Of these patients, 12.9% had 2 prior RT courses, and 67.7% received PBT with concurrent chemotherapy. Median follow-up was 7.2 months (0.9-64.7). Post-PBT, there were 16.7% locoregional only, 11.1% distant only, and 16.7% locoregional and distant recurrences. Six-month LC, DMFS, and OS were 80.5%, 83.4%, and 69.1%, respectively. One-year LC, DMFS, and OS were 67.1%, 83.4%, and 27%, respectively. Acute grade ≥3 toxicities occurred in 23% of patients, with 1 acute grade 5 toxicity secondary to esophageal hemorrhage, unclear if related to reRT or disease progression. No grade ≥3 late toxicities were reported. Conclusions: In the largest report to date of PBT for reRT in patients with recurrent EC, we observed acceptable acute toxicities and encouraging rates of disease control. However, these findings are limited by the poor prognoses of these patients, who are at high risk of mortality. Further research is needed to better assess the long-term benefits and toxicities of PBT in this specific patient population.

Patterns of progression after immune checkpoint inhibitors for Hodgkin lymphoma: implications for radiation therapy.

ABSTRACT: Immune checkpoint inhibitors (ICIs) have demonstrated remarkable response rates in relapsed or refractory Hodgkin lymphoma (HL). Still, most patients eventually progress. Patterns of progression after ICIs are not well described and are essential to defining the role of local therapies in combination with ICIs. We identified patients who received ICIs for HL between 2013 and 2022. Fludeoxyglucose-18 positron emission tomography (FDG-PET) before initiating ICI and at progression on/after ICI were reviewed, and areas of active HL were recorded. An exploratory analysis of treatable progression included patients with ≤5 sites of disease on pre-ICI FDG-PET and progression only at pre-ICI sites. Ninety patients were identified; 69 had complete records, and of these, 32 (52%) had relapsed at ICI initiation, 17 (25%) were refractory, and 16 (23%) received ICI as first-line therapy. Forty-five of 69 patients had ≤5 sites of disease (limited) on pre-ICI FDG-PET. Patients with >5 sites of disease had a higher risk of progression, and every site of disease >5 sites conferred an additional 1.2x higher chance of progression. At a median follow-up of 4.0 years, 41 of 69 patients had progressed on/after ICIs (cumulative incidence 66.4%), and of these, 22 of 41 patients progressed only at pre-ICI sites (cumulative incidence 39.4%). In an exploratory analysis, the cumulative incidence of a treatable progression among 45 patients with limited disease was 34%. The cumulative incidence of any progression among this cohort was 58.9%. More than one-third of patients with limited disease before ICIs experienced progression only at pre-ICI sites of disease. These patients could be candidates for radiation during or after ICIs.

Development and Dosimetric Characterization of a Customizable Shield for Subtotal Skin Electron Beam Therapy.

Purpose: Purpose: Subtotal skin electron beam therapy may be an option for patients with cutaneous lymphoma receiving radiation therapy to treat large areas of their skin but may benefit from sparing specific areas that may have had previous radiation therapy, are of specific cosmetic concern, and/or show no evidence of disease. We report here on the design, implementation, and dosimetric characteristics of a reusable and transparent customizable shield for use with the large fields used to deliver total skin electron beam therapy at extended distance with a conventional linear accelerator. Methods and Materials: A shield was designed and manufactured consisting of acrylic blocks that can be mounted on a steel frame to allow patient-specific shielding. The dosimetry of the device was measured using radiochromic film. Results: The shield is easy to use and well-tolerated for patient treatment, providing minimal electron transmission through the shield with a sharp penumbra at the field edge, with no increase in x-ray dose. We report on the dosimetry of a commercial device that has been used to treat more than 30 patients to date. Conclusions: The customizable shield is well suited to providing patient-specific shielding for subtotal skin electron beam therapy.

Don't Put the CART Before the Horse: The Role of Radiation Therapy in Peri-CAR T-cell Therapy for Aggressive B-cell Non-Hodgkin Lymphoma.

PURPOSE: The optimal approach to incorporate radiation therapy (RT) in conjunction with chimeric antigen receptor (CAR) T-cell therapy (CART) for relapsed/refractory (r/r) B-cell non-Hodgkin lymphoma (bNHL) remains unclear. This study documented the RT local control rate among patients who received bridging radiation therapy (BRT) before CART and compares it with those who received salvage radiation therapy (SRT) after CART. This article further reports on a promising way to use SRT for post-CART disease and identifies predictors for RT in-field recurrence. METHODS AND MATERIALS: We retrospectively reviewed 83 patients with r/r bNHL who received CART and RT, either as BRT pre-CART infusion (n = 35) or as SRT post-CART infusion (n = 48), between 2018 and 2021. RT was defined as comprehensive (compRT; ie, treated all sites of active disease) or focal (focRT). Limited disease was defined as disease amenable to compRT, involving <5 active disease sites. RESULTS: At time of RT, patients who received BRT before CART had bulkier disease sites (median diameter, 8.7 vs 5.5 cm; P = .01) and were treated to significantly lower doses (median equivalent 2-Gy dose, 23.3 vs 34.5 Gy; P = .002), compared with SRT post-CART. Among 124 total irradiated sites identified, 8 of 59 (13%) bridged sites and 21 of 65 (32%) salvaged sites experienced in-field recurrence, translating to 1-year local control rates (LC) of 84% and 62%, respectively (P = .009). Patients with limited post-CART disease (n = 37) who received compSRT (n = 26) had better overall survival (51% vs 12%; P = .028), freedom from subsequent progression (31% vs 0%; P < .001), and freedom from subsequent event (19% vs 0%; P = .011) compared with patients with limited disease who received focSRT (n = 11). CONCLUSIONS: BRT followed by CART appears to be associated with improved LC compared with SRT in r/r bNHL. Nonetheless, SRT offers a promising salvage intervention for limited (<5 sites) relapsed post-CART disease if given comprehensively.

Clinical outcomes for hilar and extrahepatic cholangiocarcinoma with adjuvant, definitive, or liver transplant-based neoadjuvant chemoradiotherapy strategies: a single-center experience.

Background: We report our experience with 3 strategies for treating hilar and extrahepatic cholangiocarcinoma (CCA) including chemoradiotherapy: neoadjuvant chemoradiotherapy (nCRT) and orthotopic liver transplant, surgical resection and adjuvant chemoradiotherapy (aCRT), and definitive chemoradiotherapy (dCRT). Methods: We included patients treated from 1998 through 2019. Kaplan-Meier estimates, log-rank testing, and univariate/multivariate Cox models were used to assess outcomes (local progression-free survival, disease-free survival, and overall survival). Results: Sixty-five patients (nCRT, n=20; aCRT, n=16; dCRT, n=29) met inclusion criteria [median (range) age 65 years (27-84 years)]. Median posttreatment follow-up was 19.1 months (0.8-164.8 months) for all patients and 38.6, 24.3, and 9.0 months for the nCRT, aCRT, and dCRT groups, respectively. At 3 and 5 years, overall survival was 78% and 59% for the nCRT group; 47% and 35%, aCRT group; and 11% and 0%, dCRT group. Compared with the dCRT group, the nCRT group (hazard ratio =0.13, 95% CI: 0.05-0.33) and the aCRT group (hazard ratio =0.29, 95% CI: 0.14-0.64) had significantly improved overall survival (P<0.001). The 5-year local progression-free survival (50% nCRT vs. 30% aCRT vs. 0% dCRT, P<0.001) and 5-year disease-free survival (61% nCRT vs. 30% aCRT vs. 0% dCRT, P=0.01) were significantly better for strategies combined with surgery. Conclusions: Outcomes for patients with extrahepatic CCA were superior for those who underwent nCRT/orthotopic liver transplant or postsurgical aCRT than for patients treated with dCRT. The excellent outcomes after nCRT/orthotopic liver transplant provide additional independent data supporting the validity of this strategy. The poor survival of patients treated with dCRT highlights a need for better therapies when surgery is not possible.

Does bridging radiation therapy affect the pattern of failure after CAR T-cell therapy in non-Hodgkin lymphoma?

PURPOSE: Analyze the pattern of disease failure after anti-CD19-directed chimeric antigen receptor T-cell therapy (CART) for non-Hodgkin lymphoma, assess the local control rate of bridging radiotherapy (bRT) and characterize in-field recurrences. METHODS: We retrospectively reviewed 120 patients with NHL who received CART between 2018 and 2020. Baseline characteristics and treatment outcomes were compared between patients who received bRT and those who did not (noRT). RESULTS: Of the 118 patients included, 14 (12%) received bRT, while 104 (88%) did not. bRT group had more localized and extranodal disease. bRT was delivered with a median dose of 20 Gy (range: 15-36) in 5 fractions (range: 3-24). Pattern of failure analysis revealed that progression involving pre-existing sites was the predominant pattern of failure in both the bRT and noRT groups (86% and 88%, respectively). Median duration of response was 128 days (range: 25-547) for bRT group and 93 days (range: 22-965) for noRT group (p = 0.78). In the bRT group, only 2/15 sites irradiated had infield recurrence and where characterized by bulky disease, SUVmax >20, elevated LDH at the time of CART infusion, and extranodal involvement. The bRT 1-year LC was 86%. Median duration of local response was 257 days (range: 25-630) for radiation-bridged sites. CONCLUSION: Majority of progressions after CART infusion involve pre-existing sites. Bridging RT prior to CART provides excellent in-field local control and durable response. Patients with bulky disease, SUVmax >20, elevated LDH, and extranodal involvement are likely at higher risk of in-field recurrence after bRT and may benefit from higher curative doses of bRT.

Long-Term Results of a Phase 1 Dose-Escalation Trial and Subsequent Institutional Experience of Single-Fraction Stereotactic Ablative Radiation Therapy for Liver Metastases.

PURPOSE: We report long-term outcomes from our phase 1 dose-escalation study to determine the maximum tolerated dose of single-fraction liver SABR pooled with our subsequent single institutional experience with patients treated postprotocol at the highest dose level (40 Gy) established from the phase 1 study. METHODS AND MATERIALS: Patients with liver metastases from solid tumors located outside of the central liver zone were treated with single-fraction SABR on a phase 1 dose escalation trial. At least 700 cc of normal liver had to receive <9.1 Gy. Seven patients with 10 liver metastases received the initial prescription dose of 35 Gy, and dose was then escalated to 40 Gy for 7 more patients with 7 liver metastases. An additional 19 postprotocol patients with 22 liver metastases were treated to 40 Gy in a single fraction. Patients were followed for toxicity and underwent serial imaging to assess local control. RESULTS: Median imaging follow-up for the combined cohort (n = 33, 39 lesions) was 25.9 months; 38.9 months for protocol patients and 20.2 months for postprotocol patients. Median lesion size was 2.0 cm (range, 0.5-5.0 cm). There were no dose-limiting toxicities observed for protocol patients, and only 3 grade 2 toxicities were observed in the entire cohort, with no grade ≥3 toxicities attributable to treatment. Four-year actuarial local control of irradiated lesions in the entire cohort was 96.6%, 100% in the protocol group and 92.9% in the subsequent patients. Two-year overall survival for all treated patients was 82.0%. CONCLUSIONS: For selected patients with liver metastases, single-fraction SABR at doses of 35 and 40 Gy was safe and well-tolerated, and shows excellent local control with long-term follow-up; results in subsequent patients treated with single-fraction SABR doses of 40 Gy confirmed our earlier results.

Technical Note: 4D robust optimization in small spot intensity-modulated proton therapy (IMPT) for distal esophageal carcinoma.

PURPOSE: To compare the dosimetric performances of small-spot three-dimensional (3D) and four-dimensional (4D) robustly optimized intensity-modulated proton (IMPT) plans in the presence of uncertainties and interplay effect simultaneously for distal esophageal carcinoma. METHOD AND MATERIALS: Thirteen (13) patients were selected and re-planned with small-spot ( σ  ~ 2-6 mm) 3D and 4D robust optimization in IMPT, respectively. The internal clinical target volumes (CTVhigh3d , CTVlow3d ) were used in 3D robust optimization. Different CTVs (CTVhigh4d , CTVlow4d ) were generated by subtracting an inner margin of the motion amplitudes in three cardinal directions from the internal CTVs and used in 4D robust optimization. All patients were prescribed the same dose to CTVs (50 Gy[RBE] for CTVhigh3d /CTVhigh4d and 45 Gy[RBE] for CTVlow3d /CTVlow4d ). Dose-volume histogram (DVH) indices were calculated to assess plan quality. Comprehensive plan robustness evaluations that consisted of 300 perturbed scenarios (10 different motion patterns to consider irregular motion (sampled from a Gaussian distribution) and 30 different uncertainties scenarios (sampled from a 4D uniform distribution) combined), were performed to quantify robustness to uncertainties and interplay effect simultaneously. Wilcoxon signed-rank test was used for statistical analysis. RESULTS: Compared to 3D robustly optimized plans, 4D robustly optimized plans had statistically improved target coverage and better sparing of lungs and heart (heart Dmean , P = 0.001; heart V30Gy[RBE] , P = 0.001) in the nominal scenario. 4D robustly optimized plans had better robustness in target dose coverage (CTVhigh4d V100% , P = 0.002) and the protection of lungs and heart (heart Dmean , P = 0.001; heart V30Gy[RBE] , P = 0.001) when uncertainties and interplay effect were considered simultaneously. CONCLUSIONS: Even with small spots in IMPT, 4D robust optimization outperformed 3D robust optimization in terms of normal tissue protection and robustness to uncertainties and interplay effect simultaneously. Our findings support the use of 4D robust optimization to treat distal esophageal carcinoma with small spots in IMPT.