Malignant Pleural Mesothelioma and Radiotherapy: Lung Toxicity Results of an Interim Analysis in Prospective Pilot Trial

PURPOSE/OBJECTIVE(S)

Malignant Pleural Mesothelioma (MPM) is a rare but aggressive intrathoracic malignancy with an overall poor prognosis. Neoadjuvant chemotherapy, surgery and then radiotherapy is the standard of care in early-stage disease. Our study aim is to evaluate the feasibility and toxicity of the novel adjuvant RT in accelerated hypofractionation. We report the lung toxicity preliminary results of the first patients entreated.

MATERIALS/METHODS

Starting in 2017, 29 MPM patients were enrolled in the trial (IRST trial 163). All patients were treated with accelerated hypofractionated radiotherapy using a helical 3-D CRT and IMRT system and intensity-modulated arc therapy. We conducted a prospective mono-institutional clinical trial enrolling cyto-histological proven, MPM patients. The major exclusion criteria were: previous thorax radiotherapy, contralateral mediastinum involvement (N3) and/or M1, interstitial pneumopathy, active pneumonitis, and fissural disease. The prescription dose was 30 Gy in five daily fractions, while an inhomogeneous dose escalation to 40 Gy was prescribed based solely upon the presence of gross residual tumor. All patients were treated in a 3-D CRT and IMRT system. Patients underwent functional lung study before to start radiotherapy treatment, 2 months and 6 months after the end of the treatment. The organs at risk dose-volume histograms were converted to a 2-Gy equivalent dose, and we closely adhered to the dose constraints of the literature data. We in particular analyzed lung toxicity of the first 20 patients.

RESULTS

No G3/G4 lung toxicity was found. We reported 65.0% G1 pneumonitis and 10% G2 as acute lung toxicity. The majority of the G1 patients had only mild symptoms and pneumonitis was described only for radiologic features with no need for medical therapy. Other respiratory toxicities were G1-G2 cough in 50% of the patients; G1 dyspnea occurred in 65% of the patients and G2 in the 15%. The total lung mean dose was 18 Gy (range 13 Gy-23 Gy), and the contralateral lung mean dose was 2 Gy (range 1 Gy-2 Gy). The median value of Forced Expired Volume in one second (FEV1) recorded was 75.5% (range: 46%-137%) before the treatment was started, the median value of Forced Vital Capacity (FVC) at baseline was 74 (range 46-123) with progressive decreasing values through time. DLCO has also been reported with a progressive decrease over time after radiotherapy treatment. No case of respiratory failure was reported after treatment.

CONCLUSION

Treatment of the intact lung with pleural intensity-modulated arc irradiation is a novel treatment strategy that appears to be safe, feasible, and without a high grade of lung toxicity. More investigations are mandatory. The protocol is ongoing.

Hyperbaric Oxygen Therapy plus Hypofractionated Stereotactic Radiotherapy in Recurrent Glioblastoma

PURPOSE/OBJECTIVE(S)

Hypoxia is thought to play a role in tumor development, angiogenesis and growth, and resistance to chemotherapy, antiangiogenic therapy and radiotherapy (RT) in a large number of human cancers. Brain tumors, especially highly aggressive GBM with its necrotic tissue, are more likely to be affected by hypoxia. The median partial pressure of oxygen (PO2) of high-grade gliomas in patients under anesthesia was approximately 5-7 mmHg, with a significant proportion of PO2 values <2.5 mmHg. The radiosensitivity of brain tumors could potentially be increased by performing hyperbaric oxygenation (HBO) before the RT session. We propose an innovative approach to improve the efficacy of accelerated hypofractionated Stereotactic Radiotherapy (HSRT) after HBO (HBO-RT) for the treatment of recurrent HGG (rHGG). The primary objective of this study is to evaluate the disease control rate (DCR) at 3 months. The secondary Objectives are: - Safety assessment (acute and late toxicity). - Overall Survival (OS), - Progression Free Survival (PFS).

MATERIALS/METHODS

We enrolled 14 patients (aged >18 years) with rHGG detected using MRI. A total dose of 15-25 Gy was administered in daily 5-Gy fractions for 3-5 consecutive days after daily HBO.

RESULTS

Median follow-up from re-irradiation was 22.8 months (range: 2.0-24.2 months). The disease control rate 3-months after HBO-RT was 50% (23.0-76.9). Six- and 12-month Progression-free survival was 35.7% (95% CI: 13-59.4) and 10.7% (95% CI: 0.8-35.4), respectively. Median overall survival of HBO-RT was 10.7 months (95% CI: 6.6-24.2). No acute or late neurologic toxicity >grade (G)2 was observed.

CONCLUSION

HSRT combined to HBO seems effective and safe in the treatment of rHGG.

Abstract P1-05-13: Clinical impact of whole-body magnetic resonance imaging on subsequent management in luminal/HER2-negative breast cancer patients

Background: Routine imaging can be inaccurate, especially in metastatic breast cancer (MBC) with bone-only disease or mainly bone disease. This analysis investigates how the use of whole-body magnetic resonance imaging (WB-MRI), in addition to routine computed tomography (CT) and bone scintigraphy (BS), can influence treatment decisions in patients with known MBC. Methods: In a prospective observational study, in our Institute, we performed WB-MRI as baseline and follow-up examination in addition to routine imaging (CT, BS) in luminal/HER2-negative BC patients with prevalence of bone disease potentially candidate to CDK 4/6 inhibitors. All examinations were interpreted by two experienced radiology specialists. Using the results of the examination, a multidisciplinary oncology committee (MOC) reported on the treatment strategy. A positive impact on clinical management was considered if the examination determined a modification in the treatment strategy compared to the MOC decision before WB-MRI. Results: Thirty consecutive luminal breast cancer patients in a metastatic setting at standard imaging were recruited. All these patients underwent CT and BS followed by WB-MRI study. At standard imaging, fourteen patients (46.7%) presented with bone-only disease, while eight patients (26.6%) did not show bone lesions. In 18 of 30 cases (60%) WB-MRI led to a modification of the therapeutic approach. Due to the detection of new metastatic lesions or progression of known metastatic sites, reported on WB-MRI alone, the therapeutic decision changed in 6 (20%) and 3 (10%) patients, respectively. In one patient (3%) the therapeutic decision changed because of both findings. Nine patients (30%) started a new therapeutic line due to evidence of progressive disease on WB-MRI, while 4 patients (13.3%) underwent radiotherapy and 1 patient received orthopaedic counselling for high risk WB-MRI-assessed bone lesions. In 8 patients (26.6%) the disease was re-classified as early breast cancer based on WB-MRI assessment. Conclusions: WB-MRI could play a role in the clinical assessment of luminal MBC. Further studies are needed to better address the potential use of WB-MRI in the assessment and monitoring of bone only/bone predominant luminal MBC and/or in equivocal cases.

Citation Format: Filippo Merloni, Michela Palleschi, Alice Rossi, Andrea Prochowski Iamurri, Caterina Gianni, Samanta Sarti, Francesca Mannozzi, Federica Fiori, Giandomenico Di Menna, Lorenzo Cecconetto, Marianna Sirico, Chiara Casadei, Sara Bleve, Lorenzo Gasperoni, Roberto Casadei, Luca Tontini, Antonino Romeo, Domenico Barone, Ugo De Giorgi. Clinical impact of whole-body magnetic resonance imaging on subsequent management in luminal/HER2-negative breast cancer patients [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P1-05-13.

Prognostication in palliative radiotherapy—ProPaRT: Accuracy of prognostic scores

Background

Prognostication can be used within a tailored decision-making process to achieve a more personalized approach to the care of patients with cancer. This prospective observational study evaluated the accuracy of the Palliative Prognostic score (PaP score) to predict survival in patients identified by oncologists as candidates for palliative radiotherapy (PRT). We also studied interrater variability for the clinical prediction of survival and PaP scores and assessed the accuracy of the Survival Prediction Score (SPS) and TEACHH score.

Materials and methods

Consecutive patients were enrolled at first access to our Radiotherapy and Palliative Care Outpatient Clinic. The discriminating ability of the prognostic models was assessed using Harrell’s C index, and the corresponding 95% confidence intervals (95% CI) were obtained by bootstrapping.

Results

In total, 255 patients with metastatic cancer were evaluated, and 123 (48.2%) were selected for PRT, all of whom completed treatment without interruption. Then, 10.6% of the irradiated patients who died underwent treatment within the last 30 days of life. The PaP score showed an accuracy of 74.8 (95% CI, 69.5–80.1) for radiation oncologist (RO) and 80.7 (95% CI, 75.9–85.5) for palliative care physician (PCP) in predicting 30-day survival. The accuracy of TEACHH was 76.1 (95% CI, 70.9–81.3) and 64.7 (95% CI, 58.8–70.6) for RO and PCP, respectively, and the accuracy of SPS was 70 (95% CI, 64.4–75.6) and 72.8 (95% CI, 67.3–78.3).

Conclusion

Accurate prognostication can identify candidates for low-fraction PRT during the last days of life who are more likely to complete the planned treatment without interruption.

All the scores showed good discriminating capacity; the PaP had the higher accuracy, especially when used in a multidisciplinary way.

Radiotherapy and High-Dose Interleukin-2: Clinical and Immunological Results of a Proof of Principle Study in Metastatic Melanoma and Renal Cell Carcinoma

High-dose interleukin-2 (HD IL-2) has curative potential in metastatic melanoma (MM) and renal cell carcinoma (RCC). Radiotherapy (RT) kills cancer cells and induces immunomodulatory effects. Prospective trials exploring clinical and immunological properties of combined RT/HD IL-2 are still needed. We designed a phase II, single-arm clinical trial for patients with MM and RCC. The treatment schedule consisted of 3 daily doses of 6-12 Gy of RT to 1-5 non-index metastatic fields, before IL-2 at the first and third treatment cycle. HD IL-2 was administered by continuous infusion for 72 hours and repeated every 3 weeks for up to 4 cycles, thereafter every 4 weeks for a maximum of 2 cycles. The primary endpoint was the immunological efficacy of the combined RT/HD IL-2 treatment (assessed by IFN-γ ELISPOT). Nineteen out of 22 patients were evaluable for immunological and clinical response. Partial response occurred in 3 (15.7%) patients and stable disease was observed in 7 (36.8%). The disease control rate was 52.6% after a median follow up of 39.2 months. According to Common Terminology Criteria for Adverse Events 4.0 (CTCAE 4.0), the majority of toxicities were grade 1-2. Immunological responses were frequent and detected in 16 (84.2%) patients. Increased levels of IL-8 and IL-10 in melanoma, circulating effector memory CD4+ and intratumoral CD8+ T cells in both tumor types were detected after therapy. Overall the treatment was well tolerated and immunologically active. Immunomonitoring and correlative data on tumor and peripheral blood cell subsets suggest that this combination treatment could be a promising strategy for patients progressing after standard treatments.

Multimodal Treatment with GEMOX Plus Helical Tomotherapy in Unresectable Locally Advanced Pancreatic Cancer: A Pooled Analysis of Two Phase 2 Studies

In locally advanced pancreatic cancer (LAPC), the combination of chemotherapy and radiotherapy is a widely used treatment option. We performed a pooled analysis, including an exploratory analysis for prognostic and predictive factors, of two phase 2 trials including 73 patients with LAPC, treated with gemcitabine and oxaliplatin (GEMOX) and hypofractionated tomotherapy. With a median follow-up of 36 months (range 1–65), median progression-free (PFS) and overall survival (OS) were 10.2 (95% confidence interval [CI] 7.8–13.2) and 14.3 (95% CI 12.0–18.1) months, respectively. The overall resectability rate was 23.3% (95% CI 13.6–33.0), and the R0 resection rate was 13.7% (95% CI 5.8–21.6). In the multivariate analysis, ECOG performance status (PS) 0 and low levels of CA 19–9 were associated with improved OS and PFS. Concerning OS, log(CA19–9) resulted in a hazard ratio (HR) of 1.20 (95% CI 1.02–1.42), p = 0.027. For ECOG PS 0, HR was 1.00; for PS 1, HR was 2.69 (95% CI 1.46–4.96); for PS 2, HR was 4.18 (95% CI 0.90–19.46); p = 0.003. Low CA19–9 levels were also predictive for resection, with an odds ratio of 0.71 (95% CI 0.52–0.97), p = 0.034. In conclusion, GEMOX and hypofractionated radiotherapy is a treatment option in LAPC. Further studies are needed to identify differences in tumor biology, which may help to predict resectability and prognosis.

Complete pathological response in locally advanced non-small-cell lung cancer patient: A case report

BACKGROUND

Chemotherapy and radiotherapy followed by durvalumab is currently the standard treatment for locally advanced node-positive non-small-cell lung cancer (NSCLC). We describe the case of a patient with locally advanced node-positive NSCLC (LA-NSCLC) treated in a phase II prospective protocol with chemotherapy, accelerated hypofractionated radiotherapy (AHRT) and surgery in the pre-immunotherapy era.

CASE SUMMARY

A 69-year-old male, ex-smoker (20 PY), with a Karnofsky performance status of 90, was diagnosed with locally advanced squamous cell lung carcinoma. He was staged by total body computed tomography (CT) scanning, and integrated ¹⁸F-fluorodeoxyglucose positron emission tomography/CT scan [cT4 cN3 cM0, stage IIIC according to TNM (tumor-node-metastasis) 8^th edition] and received AHRT between chemotherapy cycles, in accordance with the study protocol (EudractCT registration 2008-006525-14). At the end of the study the patient underwent surgery, which was not part of the protocol, and showed a complete pathological response.

CONCLUSION

This case report confirms that AHRT can be used successfully to treat primary LA-NSCLC with bilateral mediastinal lymph node involvement. Our case is of particular interest because of the pathological response after AHRT and the lack of surgical complications. We hypothesize that this radiotherapeutic approach, with its proven efficacy, could be delivered as a short course reducing treatment costs, increasing patient compliance and reducing toxicity. We are currently investigating the possibility of combining hypofractionation, chemotherapy and immunotherapy for patients with LA-NSCLC.

Role of Hyperbaric Oxygenation Plus Hypofractionated Stereotactic Radiotherapy in Recurrent High-Grade Glioma

Background

The presence of hypoxic cells in high-grade glioma (HGG) is one of major reasons for failure of local tumour control with radiotherapy (RT). The use of hyperbaric oxygen therapy (HBO) could help to overcome the problem of oxygen deficiency in poorly oxygenated regions of the tumour. We propose an innovative approach to improve the efficacy of hypofractionated stereotactic radiotherapy (HSRT) after HBO (HBO-RT) for the treatment of recurrent HGG (rHGG) and herein report the results of an ad interim analysis.

Methods

We enrolled a preliminary cohort of 9 adult patients (aged >18 years) with a diagnosis of rHGG. HSRT was administered in daily 5-Gy fractions for 3-5 consecutive days a week. Each fraction was delivered up to maximum of 60 minutes after HBO.

Results

Median follow-up from re-irradiation was 11.6 months (range: 3.2-11.6 months). The disease control rate (DCR) 3 months after HBO-RT was 55.5% (5 patients). Median progression-free survival (mPFS) for all patients was 5.2 months (95%CI: 1.34-NE), while 3-month and 6-month PFS was 55.5% (95%CI: 20.4-80.4) and 27.7% (95%CI: 4.4-59.1), respectively. Median overall survival (mOS) of HBO-RT was 10.7 months (95% CI: 7.7-NE). No acute or late neurologic toxicity >grade (G)2 was observed in 88.88% of patients. One patient developed G3 radionecrosis.

Conclusions

HSRT delivered after HBO appears to be effective for the treatment of rHGG, it could represent an alternative, with low toxicity, to systemic therapies for patients who cannot or refuse to undergo such treatments.

Clinical Trial Registration

www.ClinicalTrials.gov, identifier NCT03411408.

Re-irradiation of recurrent glioblastoma using helical TomoTherapy with simultaneous integrated boost: preliminary considerations of treatment efficacy

Although there is still no standard treatment for recurrent glioblastoma multiforme (rGBM), re-irradiation could be a therapeutic option. We retrospectively evaluated the efficacy and safety of re-irradiation using helical TomoTherapy (HT) with a simultaneous integrated boost (SIB) technique in patients with rGBM. 24 patients with rGBM underwent HT-SIB. A total dose of 20 Gy was prescribed to the Flair (fluid-attenuated inversion recovery) planning tumor volume (PTV) and 25 Gy to the PTV-boost (T1 MRI contrast enhanced area) in 5 daily fractions to the isodose of 67% (maximum dose within the PTV-boost was 37.5 Gy). Toxicity was evaluated by converting the 3D-dose distribution to the equivalent dose in 2 Gy fractions on a voxel-by-voxel basis. Median follow-up after re-irradiation was 27.8 months (range 1.6-88.5 months). Median progression-free survival (PFS) was 4 months (95% CI 2.0-7.9 months), while 6-month PFS was 41.7% (95% CI 22.2-60.1 months). Median overall survival following re-irradiation was 10.7 months (95% CI 7.4-16.1 months). There were no cases of re-operation due to early or late toxicity. Our preliminary results suggest that helical TomoTherapy with the proposed SIB technique is a safe and feasible treatment option for patients with rGBM, including those large disease volumes, reducing toxicity.