A review of staging chest CT in trunk and extremity soft tissue sarcoma

To determine the incidence of pulmonary metastases on chest CT in trunk and extremity soft tissue sarcoma based on two size criteria, and to identify factors associated with metastases.

Retrospective review of chest CT studies in patients with trunk and extremity soft tissue sarcoma over an 18-month period. Data collected included patient age/sex, tumour location, size and relationship to fascia. All chest CTs were reviewed for the presence of metastases which were diagnosed according to two size criteria: multiple nodules > 5 mm in size or multiple nodules > 10 mm in size. Follow-up CT studies were reviewed in cases initially considered indeterminate.

127 males and 73 females were included (mean age 57.1 years; range 10-90 years). 147 (73.5%) tumours were deep to the fascia and 53 (26.5%) superficial. Tumour size classified according to the 12 AJCC 2019 criteria was: T1 = 52, T2 = 76, T3 = 39, T4 = 33. Based on nodule size >5 mm, 73 (36.5%) patients had no metastases, 42 (21%) had metastases, while 85 (42.5%) studies were indeterminate. Based on nodule size >10 mm, 73 (36.5%) patients had no metastases, 28 (14%) had metastases, while 99 (49.5%) studies were indeterminate. Larger maximum dimension of the primary tumour was a risk factor for pulmonary metastases using both size criteria.

The incidence of pulmonary metastases at presentation in trunk and extremity soft tissue sarcoma is 14-21%. 42.5-49.5% of chest CTs were indeterminate.

The incidence of pulmonary metastases at presentation in trunk and extremity soft tissue sarcoma is 14-21%. Indeterminate pulmonary nodules are also very common.