Smoking is predictive of poorer distant metastasis-free and progression free-survival in soft tissue sarcoma patients treated with pre-operative radiotherapy or chemoradiotherapy

BACKGROUND: Soft tissue sarcomas (STS) are often treated with pre-operative radiation (RT), with or without chemotherapy, followed by wide local excision. Prognosis for these patients involves an interplay of tumor and patient characteristics. Known prognostic determinants include tumor size, grade, response to therapy, and patient characteristics such as age. While smoking is negatively correlated with outcomes in various malignancies, the impact on STS is unknown. We aimed to assess if smoking impacts overall (OS), distant metastasis-free (DMFS), and progression-free (PFS) survival in patients with STS treated with pre-operative RT. METHODS: Between 2000 and 2015, 166 patients with STS were identified from our prospective database. Patient variables were retrospectively reviewed. Smoking was defined as a ≥ 10 pack year history of current and former smokers. Survival was evaluated using the fisher exact test for univariate (UVA) and logistic regression for multivariate (MVA) analysis. RESULTS: Fifty-seven (34.3%) patients had smoking histories of ≥ 10 pack years. On UVA, smoking was associated with decreased DMFS (p = 0.0009) and PFS (p = 0.0036), but not OS (p = 0.05). Smoking held significance on MVA for both DMFS and PFS. Current smokers and patients with ≥ 24-month follow-up demonstrated decreased DMFS and PFS on UVA and MVA. CONCLUSIONS: Current smokers and patients with a significant smoking history demonstrated decreased DMFS and PFS in STS patients treated with pre-operative RT. Smoking may cause immunologic compromise and therefore lead to higher rates of progression and distant metastasis.