A phase I study of the combination of atezolizumab, tiragolumab, and stereotactic body radiation therapy in patients with metastatic multiorgan cancer

BACKGROUND

Immunotherapy targeting the PD-1/PD-L1 pathway is a standard of care in a number of metastatic malignancies, but less than a fifth of patients are expected to respond to ICIs (Immune Checkpoint Inhibitors). In a clinical trial, combining the anti-TIGIT (T cell immunoreceptor with Ig and ITIM domains) Mab (monoclonal antibody) tiragolumab with atezolizumab improved outcomes in non-small cell lung cancer. In preclinical models, SBRT (Stereotactic Body Radiation Therapy) could increase expression levels of the inhibitory co-receptors TIGIT and PD-L1. We aim to assess the combination of tiragolumab with atezolizumab and SBRT in metastatic, previously treated by ICIs, non-small cell lung cancer, head and neck cancer, bladder cancer, and renal cell cancer.

METHODS

This phase I study (ClinicalTrials.gov NCT05259319) will assess the efficacy and safety of the combination of atezolizumab with tiragolumab and stereotactic body radiation therapy in patients with histologically proven metastatic non-small cell lung cancer, renal cell cancer, bladder cancer, and head and neck cancer previously treated. First part: 2 different schedules of SBRT in association with a fixed dose of atezolizumab and tiragolumab will be investigated only with metastatic non-small cell lung cancer patients (cohort 1). The expansion cohorts phase will be a multicentric, open-label study at the recommended scheme of administration and enroll additional patients with metastatic bladder cancer, renal cell cancer, and head and neck cancer (cohort 2, 3 and 4). Patients will be treated until disease progression, unacceptable toxicity, intercurrent conditions that preclude continuation of treatment, or patient refusal in the absence of progression or intolerance. The primary endpoint of the first phase is the safety of the combination in a sequential or concomitant scheme and to determine the expansion cohorts phase recommended scheme of administration. The primary endpoint of phase II is to evaluate the efficacy of tiragolumab + atezolizumab + SBRT in terms of 6-month PFS (Progression-Free Survival). Ancillary analyses will be performed with peripheral and intratumoral immune biomarker assessments.

TRIAL REGISTRATION

This study is registered on ClinicalTrials.gov: NCT05259319, since February 28th, 2022.

Intra Fraction Organs at Risk Movements in Adaptive Radiotherapy of Upper-Abdominal Stereotactic Body Radiotherapy on 0.35 T MR-Linac

PURPOSE/OBJECTIVE(S)

The recent development of magnetic resonance guided radiotherapy (MRgRT) has made possible adaptive radiotherapy (ART) especially for abdominal stereotactic body radiotherapy (SBRT). Online ART process allows to adapt the treatment at each fraction by considering the mobility of the organs at risk (OAR) and the target. These volumes are daily delineated and a new treatment plan is reoptimized. This process is multidisciplinary involving therapists, physicians and physicists. Time is a key element because of the presence of the patient on the treatment couch. In spite of having a well-trained team, the fraction duration is quite long, usually equal or higher than 45 min. Consequently, the elapsed time between the acquisition of the MR images used for the ART process and the end of the treatment delivery can be substantial. In this context, we decided to investigate the intra fraction OAR mobility by analyzing and comparing two images of the MR-Linac: one acquired at the beginning of the fraction and used for the ART process and another one immediately acquired at the end of the treatment delivery. The objectives of this study are to investigate the OAR mobility during the fraction and evaluate the possible impact on the dose distribution.

MATERIALS/METHODS

Twenty patients treated in 5 fractions for upper-abdominal SBRT (liver, adrenal, pancreas, adenopathy) on the 0.35 T MR-Linac of our institution have been prospectively included in this study between May 2021 and August 2021. For each fraction an additional 3D MR image has been acquired immediately at the end of the treatment delivery. The OARs (colon, small bowel and duodenum) included in the ART process have been delineated on the post-fraction images. After having registered both images of each fraction, OAR volumes and their dose distributions have been compared.

RESULTS

A high level of mobility of several OARs has been observed. For instance, a relative mean volume variation (increase or diminution) of 85%, 60% and 24% have been calculated, respectively, for the small bowel, the colon and duodenum. These level of volume variations strongly impacted the OAR dose distributions. For instance, the variation (increase or diminution) of maximum dose for colon, small bowel and duodenum was, respectively, about 4.3 Gy, 3.4 Gy and 2.8 Gy. These modifications led to exceed dose constraints in 2 fractions for colon, 4 fractions for small bowel and 3 fractions for duodenum. Nevertheless, by accumulating all the fractions, the dose constraints were always satisfied.

CONCLUSION

OARs volume modifications during ART process can be significant and lead to important dose variations. At the scale of the treatment, these dose variations respect the dose constraints. In the near future, the correlation of these volumetric variations with the duration of the fraction will be investigated.

Prognosis of local invasive relapses after carcinoma in situ of the breast: a retrospective study from a population-based registry

PURPOSE

The prognosis of local invasive recurrence (LIR) after prior carcinoma in situ (CIS) of the breast has not been widely studied and existing data are conflicting, especially considering the specific prognosis of this entity, compared to de novo invasive breast cancer (de novo IBC) and with LIR after primary IBC.

METHODS

We designed a retrospective study using data from the specialized Côte d'Or Breast and Gynecological cancer registry, between 1998 and 2015, to compare outcomes between 3 matched groups of patients with localized IBC: patients with LIR following CIS (CIS-LIR), patients with de novo IBC (de novo IBC), and patients with LIR following a first IBC (IBC-LIR). Distant relapse-free (D-RFS), overall survival (OS), clinical, and treatment features between the 3 groups were studied.

RESULTS

Among 8186 women initially diagnosed with IBC during our study period, we retrieved and matched 49 CIS-LIR to 49 IBC, and 46 IBC-LIR patients. At diagnosis, IBC/LIR in the 3 groups were mainly stage I, grade II, estrogen receptor-positive, and HER2 negative. Metastatic diseases at diagnosis were higher in CIS-LIR group. A majority of patients received adjuvant systemic treatment, with no statistically significant differences between the 3 groups. There was no significant difference between the 3 groups in terms of OS or D-RFS.

CONCLUSION

LIR after CIS does not appear to impact per se on survival of IBC.

Sequential treatment with gemcitabine/nab-paclitaxel (GA) and FOLFIRINOX (FFX) followed by stereotactic MRI-guided adaptive radiation therapy (SMART) in patients with locally advanced pancreatic cancer (LAPC): GABRINOX-ART phase 2, multicenter trial

TPS4191

Background: LAPC represents a major challenge with no standardized chemotherapy (CT) and radiotherapy (RT) treatment. Phase 2 studies (LAPACT/NEOLAP) indicated efficacy of FFX and GA, although addition of conventionally fractionated RT remains controversial. Phase 3 LAP07 trial obtained a reduction of progression free survival (PFS), albeit with no overall survival (OS) advantage. Since in metastatic pancreatic cancer we recently attained with GA/FFX sequential combination (GABRINOX) high objective response rate and promising OS with acceptable toxicity and no limiting neurotoxicity, we proposed in LAPC to complement GABRINOX with SMART, recently recognized beneficial in pancreatic tumors by a retrospective multicenter study (OS at 2 years) and our prospective registry study (dosimetric benefit of adaptation). In a first step (SEQ1), we will evaluate GABRINOX efficacy and select patients without progression for a second step (SEQ2), to evaluate feasibility and tolerance in patients without disease progression after SEQ1. Secondarily we will evaluate CT tolerance (SEQ1), acute toxicities and dosimetric results (SEQ2) and for both SEQ1+2, late toxicities, response to treatment, PFS, OS and quality of life (QoL). Methods: Naive patients with confirmed non-metastatic unresectable adenocarcinoma by centralized reading (WHO 0/1) and adequate organ function will receive in SEQ1 two cycles of GABRINOX, GA (1000 mg/m2, 125 mg/m2) on days 1, 8, and 15 followed by FFX on day 29 and 43. After 3-4 weeks, patients without progression or unacceptable toxicity will benefit from SMART (5 fractions of 10 Gy/day over 5 consecutive days). Specific dummy-run, contouring quality assurance and dosimetric plans will precede post-treatment monitoring every 6 weeks for 6 months for non-progressive patients and then every 2 months until progression: radiological assessment, biological markers (circulating tumor DNA) and QoL evaluation. Co-primary endpoints include success of SEQ1 (non-progression at 4 months, RECIST v1.1) and that of SEQ2 as absence of acute digestive non-toxicity rate > grade 3 (NCI-CTCAE v5.0) within 90 days. Based on Fleming design with maximal inefficacy (p0) of 70% and 90% (α = 2.5% and β = 5%) we need 98 and 70 patients (SEQ1 and SEQ2), and total of 103 cases considering those entering in SEQ 2 (70%) and non-evaluable patients. Success rate, toxicities (by treatment sequences) and safety (System Organ Class) by patient and cycle will be considered while dosimetry will be correlated with gastro-intestinal toxicities. Median follow-up, OS and PFS will be expressed as medians and rates with 95% CI while QoL will be explored by QLQ-C30 and QLQ-PAN26 analyses using the time to definitive deterioration. From 2021, we included 5 patients (NCT04570943). Clinical trial information: NCT04570943.

[Extreme hypofractionated radiation therapy for pancreatic cancer]

Pancreatic cancer has poor prognosis and a continuously growing incidence. By 2030, it should become the second cause of death by cancer worldwide and in France. The only curative treatment is surgery that is achievable in only 20% of patients at the time of initial diagnosis, with a high rate of incomplete resection. Neoadjuvant treatments using chemotherapy with or without radiotherapy are more often admitted to play an important role by selecting non-progressing cases who will benefit from surgery, by increasing the number of complete resection, and by making locally advanced and borderline tumours accessible to resection. However, the role of radiotherapy is still debated. Because of its dosimetric advantages, its short total duration, and its good tolerance with reduced volumes of irradiation, stereotactic radiotherapy has been largely studied. Compared to chemoradiotherapy, this technique could improve the therapeutic index helping to preserve the general status of patients in order to give them access to secondary surgery. It remains a promising technique still under evaluation, to be delivered ideally, as part of a clinical trial, or within an experimented team.

[Strategies in case of metastatic sentinel lymph node in breast cancer]

Management strategy of micro or macro metastatic sentinel lymph node(s) (SLNs) in breast cancer has dramatically changed over the past ten years and the publication of five randomized trials results: ACOSOG Z0011, IBCSG 23-01, and AATRM comparing axillary lymph node dissection (ALND) versus SLNs biopsy alone; and AMAROS and OTOASOR comparing ALND versus axillary radiotherapy. Despite methodological limitations of several of these trials, notably ACOSOG Z0011, the international recommendations (ASCO, NCCN) and the expert consensus of St Gallen do not recommend the performance of a complementary ALND in case of macro or micro metastatic SLN, if all ACOSOG Z0011 inclusion criteria are met. Moreover, in the context of a mastectomy, with one or two positive SLN and a wall irradiation indication, an axillary radiotherapy can be proposed as an alternative to ALND. Additionally, ALND is also indicated in extracapsular involvement or when three or more SLNs are metastatic. This change in strategy led to a significant decrease on the number of ALNDs performed and resulted on the abandon of SLNs extemporaneous examination. In France, there are no national recommendations on axillary management in the context of SLN involvement. Moreover, a multitude of different local guidelines, led to very heterogeneous practices in our country. The next evolution on axillary management strategy will be the implementation of a SLNs procedure after neoadjuvant chemotherapy (NAC) for patients with lymph node involvement proven before NAC and for whom NAC has allowed axillary downstaging.

[Surgery after upfront radiochemotherapy for locally advanced esophageal cancer: To do or not to do?]

The treatment of locally advanced esophageal cancer is still evolving. Surgery was considered as the backbone of the therapeutic management for a long time. Nowadays, chemoradiation has taken a major place in the neoadjuvant setting or as an exclusive treatment. Although some patients benefit from esophagectomy after chemoradiotherapy, a large subset of patients has no benefit and morbi-mortality rates are increased with a trimodality strategy. Patients who will have a local failure are at high risk of distant metastases in the follow-up. A third group of patients will have persistent locoregional disease after chemoradiotherapy and may benefit from surgery, but only a minority of patients with locally advanced disease are eligible. The impact of surgery after upfront chemoradiotherapy on survival and the quality of life of patients with locally advanced squamous cell esophageal cancer remain uncertain. An active surveillance strategy after chemoradiation or salvage esophagectomy for a locally residual disease might improve the prognosis of these patients. An optimized bimodality such as chemoradiotherapy delivering at least 50Gy is still standard and salvage surgery for local persistent disease or a local failure must be discussed in the framework of a multidisciplinary group for selected patients only.

Exclusive chemoradiation with carboplatin-paclitaxel versus FOLFOX-4 in locally advanced esophageal cancer: A matched-pair analysis

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Background: The PRODIGE 5 trial has demonstrated the safety and the efficacy of FOLFOX-4 combined with exclusive 50Gy external RT while the CROSS trial showed an improvement in overall survival with Carboplatin-Taxol (C-TAX) when combined with 41.4Gy before surgery. We sought to determine the feasibility and efficacy of exclusive RT with C-TAX compared to FOLFOX-4 regimen. Methods: 46 patients with locally advanced esophageal cancer who were treated with exclusive chemoradiation were matched 1:1 : 23 patients were treated with FOLFOX-4 regimen (group A) and 23 patients with C-TAX (group B). Comparison between the 2 groups was performed using Mac Nemar test for paired data. All tests were two sided and Pvalues were considered significant when less than 0.05. Results: The mean age in group A was 69.4 years (12.5) and 72.4 years (12.6) in group B (p = ns). In each group, 11 patients had a stage III disease at diagnosis (47.8%) with only 2 stage IV in group A (8.7%) vs none in group B. The median delivered RT doses were 50Gy [14-60] in group A while it was 50Gy [20-70] in group B. 6 courses of chemotherapy were delivered in 12 patients in group A (52.2%) and 14 patients in group B (60.9%) (p = 0.51). After chemoradiation, G1 or higher esophagitis was observed in 5 patients (26.3%) in group A and 3 patients (13.0%) in group B of whom 0 vs 2 G3 were observed in group A and B, respectively. Four patients (21.1%) had a pulmonary infection in group A and 3 in group B (13.0%). Two patients (8.7%) vs 4 patients (17.4%) had G3 neutropenia, with only 0 and 2 neutropenic fever in group A and B, respectively. Neither G3 anemia, nor G3 thrombopenia occured. After a median follow-up of 17.7 months [0.0-46.9], 25 patients had died, 14 in group A (60.9%) and 11 in group B (47.8%). The median PFS rates were 14.0 months in group A [7.7-NR] vs 12.1 months [4.4-NR] in group B (p = 0.32). The median OS rates were 20.3 months in group A [6.2-39.3] vs 17.0 months [4.8-NR] in group B (p = 0.82). Conclusions: Exclusive chemoradiation with C-TAX seems feasible with similar toxicity and survival outcomes than FOLFOX-4. The safety and efficacy of the CROSS regimen needs to be tested prospectively with RT doses > 41.4Gy in a phase II or III trial.

[Surgery alone or in association with preoperative uterovaginal brachytherapy for stage IB1 cervical cancer: Toxicities profiles]

OBJECTIVE

To assess toxicity profile in two stage-IB1 cervical cancer treatment strategies: surgery with and without preoperative uterovaginal pulsed dose-rate brachytherapy.

METHODS

A retrospective study included 45 patients presenting stage-IB1 cervical cancer without pelvic lymph-node invasion, between 2009 and 2011: 25 treated by colpohysterectomy alone (group A) and 20 with preoperative uterovaginal pulsed dose-rate brachytherapy (group B). The median follow-up was 45 and 39 months (group A and B).

RESULTS

Groups were comparable for age (median, 46.9 vs 47.6 years), histologic type (52% vs 65% squamous cell carcinoma) and tumor size (68% vs 60%, <2cm). In postoperative year 1, rates of urinary, digestive and gynaecological disorder were 39.1%, 8.7% and 15% respectively in group A versus 36.8%, 5.3% and 31.6% in group B and in year 2, 5.9%, 8.4% and 15% versus 5.6%, 5.1% and 27.8%.

DISCUSSION AND CONCLUSION

The present study comparing two stage-IB1 cervical cancer treatment strategies found no significant difference in early or late complications. In 2 months, there was greater grade-3 urinary toxicity (21.1%) and sexual disorder (15.8%) with preoperative brachytherapy but no significant difference. Exclusive surgery is probably preferable for the patient's quality of life.