Impact of elective nodal irradiation ≥ 60 Gy on severe weight loss during intensity-modulated radiation therapy in patients with head and neck squamous cell carcinoma.

BACKGROUND

This study aimed to investigate the association between radiotherapy-related factors and the incidence of severe weight loss (WL) during radiotherapy in patients with head and neck squamous cell carcinoma (HNSCC) in the intensity-modulated radiation therapy (IMRT) era.

MATERIALS AND METHODS

Seventy-nine patients with HNSCC who received IMRT between January 2011 and December 2020 were reviewed. The 10% WL was defined as severe WL. The median prescribed doses of IMRT were 70 Gy for the high-risk planning target volume (HRPTV); 60 Gy for the intermediate-risk planning target volume (IRPTV); 54 Gy for the low-risk PTV.

RESULTS

Larger volumes of ≥ 60 Gy (PTV60Gy) had a significant impact on WL, whereas volumes of ≥ 70 Gy and ≥ 54 Gy did not. PTV60Gy to the ipsilateral level II or III necks had a significant impact on WL, whereas PTV60Gy to the ipsilateral levels I, IV, V, or VII did not. The primary site of the nasopharynx/oropharynx had a significant impact on WL, whereas the hypopharynx/larynx did not. In the stepwise regression and multivariate analyses, primary site and PTV60Gy volume were important factors for severe WL.

CONCLUSIONS

Reducing the PTV60Gy volume can be useful in reducing severe WL. Because the clinical significance of IRPTV is unclear, the omission of IRPTV should be considered while balancing risks and benefits.