# Breast cancer related lymphedema and shoulder mobility following radiotherapy

## TL;DR

This study finds that radiation to a specific area in the armpit is linked to lymphedema after breast cancer treatment, but not to shoulder mobility issues.

## Contribution

The study identifies the axillary lateral thoracic artery vessel juncture as a critical area for lymphedema risk after radiotherapy.

## Key findings

- Higher radiation doses to the ALTJ correlate with increased lymphedema 12 months post-diagnosis.
- Radiation dose to the humeral head is not associated with reduced shoulder mobility.
- Multivariate analysis confirms the significance of ALTJ irradiation for lymphedema development.

## Abstract

Lymphedema of the arm and reduced shoulder mobility are common complications of breast cancer treatment. We aim to establish whether the radiation dose received by the area of the axillary lateral thoracic artery vessel juncture (ALTJ) and the shoulder joint—affect the development of the mentioned side effects.

In this retrospective study, 298 patients with early breast cancer treated surgically and with adjuvant radiation therapy, were included. Clinical data from the prospective database were used. Physiotherapists evaluated lymphedema and shoulder mobility at diagnosis, 6 and 12 months afterwards. The ALTJ, humeral head, and humeral head with a safety margin were delineated on a CT scan, and irradiation parameters were obtained from dose-volume histograms.

Multivariate analysis confirmed a correlation between higher mean (Dmean) and near-minimum (D98) radiation doses received by ALTJ and the incidence of lymphedema 12 months post-diagnosis (p = 0.016 and p = 0.002, respectively). No significant association was found between the radiation dose to the humeral head and reduced mobility.

In our cohort of patients, irradiation of the ALTJ region is associated with the occurrence of clinically-assessed lymphedema, while irradiation of the humeral head is not linked to limited mobility of the shoulder after breast cancer treatment.

The online version of this article (10.1007/s00066-025-02482-0) contains supplementary material, which is available to authorized users.