Evaluation of Prognostic Factors for Local Recurrence of Extremity Soft Tissue Sarcoma: Observational Study in a Tertiary Care Hospital

Background: Soft tissue sarcoma (STS) is a rare (1%) and heterogenous group of mesenchymal malignancies. In most of the cases (60%), it affects the extremities. Surgery is established as the mainstay of treatment, which is often complicated by local recurrence in 10-20% of the patients. This number is relatively high in a densely populated country like ours. To address this issue, extensive knowledge about the prognostic factors for local recurrence is necessary, which is unfortunately scarce for our population due to the need for more data in the literature. So, we aim to evaluate the impact of prognostic factors on local recurrence for better management and improved local recurrence-free survival of our patients.

Aim of the study: To evaluate the prognostic factors associated with local recurrence of extremity soft tissue sarcoma presenting at NICR&H.
Methods: It was a cross-sectional study conducted among 70 patients presented with local recurrence of extremity soft tissue sarcoma at the Department of Surgical Oncology in NICR&H from January 2021 to December 2021. Multiple clinicopathological and treatment-related prognostic factors were analyzed along with margin status and local recurrence using univariate and multivariate analysis.

Result: Among the 70 patients, the majority (71.4%) were below 50 years having a recurrence at the lower limb (67.15%). Pre-operative tissue diagnosis was done in only 18 (26%) patients. Forty-five of our patients (64%) underwent unplanned excision, with a significant relation (p=.03) with local recurrence. The mean time to recurrence was 13.54±6.93 months. Multiple recurrences were present in 21 (30%) patients. Fibrosarcoma (18.57%) was the most common histopathology, followed by UPS (17.14%) and Synovial Sarcoma (14.29%). Adjuvant Chemotherapy (p=.004) and Radiotherapy (p=0.017) were significantly related to local recurrence.

In association with margin status, tumour size, type of surgery, and pre-operative tissue diagnosis were statistically significant prognostic factors. Multivariate Cox regression analysis showed Marginal status, adjunct Chemotherapy, and Radiotherapy as the statistically significant prognostic factors. Moreover, survival analysis showed that those with a non-involved margin have better local recurrence-free survival.

Conclusion: The study result suggests that not all the prognostic factors for local recurrence of extremity STS are significant for our population. Tumour size, adjuvant Chemotherapy, adjuvant Radiotherapy, pre-operative tissue diagnosis, type of surgery and margin status are the most significant prognostic factors. Addressing these factors in our patients will undoubtedly improve the current scenario with local recurrence. Further large-scale study and long-term follow-up will be required to validate these findings.

Keywords: Evaluation, Prognostic Factors, Local Recurrence, SoftTissue Sarcoma, Observational Study, and Tertiary Care.