Efficacy and Toxicity of Alternative Radiation Treatment Schemes for Patients With Hematologic Malignancies: A Collaborative ILROG COVID Era Report

Purpose/Objective(s)

The COVID19 pandemic required radiation oncologists (ROs) to consider shorter treatment courses to minimize patient and staff exposure and conserve healthcare resources. Hematologic ROs adopted hypofractionated radiation therapy (hRT) regimens according to guidelines published by the International Lymphoma Radiation Oncology Group (ILROG). We report for the first time the preliminary efficacy and toxicity of these novel hypofractionated regimens in the treatment of hematologic malignancies.

Materials/Methods

We conducted a multicenter, multinational retrospective study under the direction of the ILROG. All patients receiving hRT according to ILROG guidelines from 1/1/2020 to 8/31/2020 were included. Patient and treatment details were abstracted from separate institutional databases. Toxicity was graded using CTCAE v5.0.

Results

Ninety-three patients from 4 institutions treated with 114 RT courses were included. Patient and treatment details are displayed in Table 1. Median follow up for the cohort was 179 days, and 77 patients (82%) were alive at last follow up. Maximal toxicity experienced by patients included Grade 1 (n = 16), Grade 2 (n = 1) and Grade 3 (n = 1) toxicities. Of 80 sites with response assessment within the RT field, 69% of patients achieved a complete response (n = 55), 20% partial response (n = 16), 9% stable disease (n = 7), and 2% progressive disease (n = 2). No COVID19 infections during or after RT have been documented in this patient cohort.

Conclusion

HRT according to ILROG guidelines resulted in low rates of acute toxicity and reasonable short-term treatment efficacy. Longer follow up and comparison with control groups is needed to draw more definitive conclusions and will be presented at the Annual Meeting.

2-Fluorine-18-fluoro-2-deoxy-D glucose positron emission tomography in the pretreatment staging of Hodgkin's disease: influence on patient management in a single institution

PURPOSE

Optimum therapy for patients with Hodgkin's disease (HD) is determined by a number of prognostic factors, one of which is an accurate definition of extent of disease (stage). Computerised tomography is widely used in staging but cannot reliably evaluate normal sized lymph nodes and some extranodal sites, e.g., liver, spleen and bone marrow. 2-Fluorine-18-fluoro-2-deoxy-D glucose (FDG) has been shown to concentrate preferentially in lymphoma sites (whether in nodal or extranodal tissue) and therefore may have a useful role in staging patients with HD. This study compares concurrent computerized tomography (CT) and FDG positron emission tomography (PET) in the staging of Hodgkin's disease and assesses the frequency of stage migration and possible changes in therapy related to the use of PET scanning.

PATIENTS AND METHODS

This was a single centre retrospective study of 44 patients with Hodgkin's disease who underwent both staging CT and PET prior to treatment between September 1993 and August 1998 at St. Thomas' Hospital. The number and sites of disease were assessed for each patient, documenting any stage and therapy modification prompted by PET findings.

RESULTS

One hundred fifty-nine sites of disease were demonstrated in forty-four patients by FDG-PET compared with eighty-four by CT. As a result, 18 (40.9%) patients were upstaged, nine of these by FDG-uptake in splenic or extranodal sites not visualised on CT. Only three patients were downstaged by PET results. Eleven patients (25%) had treatment modified by PET scan findings.

CONCLUSIONS

Significantly more sites of disease were identified by PET than CT resulting in stage changes and a modification of therapy in 25% of patients. This has important implications not only for current patient management but also for the design of future clinical trials.