Imaging-based evaluation of cervical muscle mass and 6-month survival in males with hypopharyngeal carcinoma.

Background: A significant proportion of newly diagnosed patients with hypopharyngeal carcinoma (HC) are at risk of early death and may not benefit from cancer treatments. Our objective was to assess whether an image-based evaluation of muscle mass could identify patients at risk of impaired survival.

Materials and methods: This retrospective study consisted of male patients diagnosed with HC treated at Helsinki University Hospital between 2005 and 2014 (N = 66). Cross-sectional areas of skeletal muscles at the level of the third cervical vertebra (C3) and at the level of the thoracic aortic apex were analyzed using magnetic resonance images and/or computed tomography images. Survival-based cutoff values for low muscle index values were determined using the receiver operating characteristics curves. Kaplan-Meier analyses and Cox proportional hazard models were used to evaluate the associations between the muscle indexes and survival rates.

Results: Several muscle indexes were associated with 6-month and 5-year survival. The 6-month survival rate of males with a low sternocleidomastoid muscle index (cutoff 1.73 cm2/m2) was 66%, as opposed to the 97% survival rate for those with an above-the-cutoff muscle index (hazard ratio 13.0 [95% CI 1.5, 116.6]). In a multivariate Cox model adjusted for age, sex, tumor stage, and grade, lower sternocleidomastoid muscle index was significantly associated with decreased 6-month survival.

Interpretation: C3-level muscle indexes, particularly the sternocleidomastoid muscle index, are a promising marker in the identification of patients at risk of early mortality and could add confidence in decision-making when choosing between active and palliative care.