ESTRO 2024 - Abstract Book

S2873

Interdiscplinary - Other

ESTRO 2024

37

Digital Poster

The Manchester experience of total lymphoid irradiation for chronic rejection post lung transplant

Sadia Ahmed 1 , Margaret Harris 2 , Karthik Santhanakrishnan 3 , Rajamiyer Venkateswaran 3 , John Blaikley 3

1 Manchester University, Medical Sciences, Manchester, United Kingdom. 2 The Christie, Clinical Oncology, Manchester, United Kingdom. 3 Manchester university NHS Foundation trust, Cardiothoracic transplant department, Manchester, United Kingdom

Purpose/Objective:

Bronchiolitis obliterans syndrome (BOS) is the most common form of chronic rejection post-lung transplantation. BOS is characterised by a 20% fall in FEV1 from the post-transplant baseline. Once diagnosed, BOS usually progresses despite treatment with enhanced immunosuppression. Total lymphoid irradiation (TLI) is a recognised therapeutic option that can be considered once other immunosuppressive measures have failed (Fisher et al 2005). The Christie have treated patients referred from the Manchester Heart and Lung Transplant Service with BOS since 2015. Here we describe our experience of the treatment.

Material/Methods:

A retrospective audit was carried out on all patients who received TLI for BOS after lung transplantation at the Christie between December 2015 and February 2023. We reviewed radiotherapy dose received, acute RTOG toxicity, effect on fall in FEV1 and median survival post treatment. We also looked at the reasons for non completion of the planned 10 fractions.TLI was conformally planned using two matching large parallel opposed beams and the Clinical Target Volume included the entire lymphatic regions (i.e., all nodal levels in the neck, axilla, mediastinum, spleen, femoral and inguinal areas) with appropriate multi-leaf collimator shielding. The treatment was given in up to 10 fractions of 0.8 Gray (Gy) over 5 weeks to a maximum planned dose of 8Gy. Clinical review and renal and full blood count was checked prior to delivery of each fraction. A Wilcoxon signed-rank test was used to compare the FEV1 value before and after TLI.

Results:

15 patients were referred for treatment during the study period but two had unfortunately deteriorated before it could be started so 13 patients with BOS (median age 61 years and range 26-68 years) underwent TLI treatment. There were 9 females and 4 males. The median interval between lung transplantation and TLI initiation was 56.9 months (range: 7.9 – 161.5 months). The median follow-up for all patients after TLI was 19.9 months (5.2 – 89.8 months). There was a variety of indications for lung transplantation seen. Five patients (38.5%) had Cystic Fibrosis, three (23.1%) patients had idiopathic pulmonary fibrosis, two (15.4%) patients had emphysema and two had chronic obstructive pulmonary disease (COPD). One patient (7.7%) had alpha-1 anti-trypsin deficiency. Nine patients (69.2%) had undergone bilateral Lung transplant and 4 (30.8%) had received a single lung. Only 2/13 (15.4%) of patients completed the total planned TLI regime (8 Gy in 10 fractions) but 9/13 (70%) completed 7/10 fractions. The commonest reason for stopping early was due to asymptomatic haematological toxicity or lethargy which resolved quickly post treatment. One patient had oesophagitis and renal toxicity but