Prognostic Factors in Indian Patients Operated for Soft Tissue Sarcomas-a Retrospective Cross-sectional Analysis

The Role of Radiotherapy in Soft Tissue Sarcoma on Extremities With Lymph Nodes Metastasis: An IPTW Propensity Score Analysis of the SEER Database

Background

Soft tissue sarcomas on extremities with regional lymph nodes metastasis (STSE-RLNM) is a devastating situation. Optimizing therapeutic approaches is vital but hampered by a shortage of randomized trials. We used a population-level database to evaluate radiotherapy’s impact on sarcoma-specific survival (SSS) and overall survival (OS) for surgery for STSE-RLNM.

Methods

We retrospectively screened data from the SEER database (2004–2015), and 265 patients with STSE-RLNM who received surgery, with (134) or without (131) radiotherapy, were enrolled in this study. A propensity-score-matched analysis with the inverse probability of treatment weighting (IPTW) Kaplan–Meier curve was created. The log-rank test and Cox regression analysis were performed to compare SSS and OS in patients with and without radiotherapy. Further analysis of radiotherapy time was conducted, and the Kaplan–Meier curve and the log-rank test were done. Landmark analysis was introduced to attenuate the immortal bias.

Results

In the original unadjusted cohort, the radiotherapy + surgery group is associated with improved SSS [hazard ratio (HR), 0.66; 95% CI, 0.47–0.91; p = 0.011] and OS (HR, 0.64; 95% CI, 0.47–0.88; p = 0.006). This significant treatment effect was also noted in IPTW-adjusted Cox regression either on SSS (HR, 0.65; 95% CI, 0.45–0.93; p = 0.020) or on OS (HR, 0.64; 95% CI, 0.46–0.91; p = 0.013). The Kaplan–Meier curve and log-rank test showed that pre- and postoperative radiotherapy was not related to SSS (p = 0.980 or OS (p = 0.890).

Conclusion

Radiotherapy and surgery has a significant benefit on the prognosis of patients with STSE-RLNM compared to surgery alone. These findings should be considered when making treatment decisions for them.

Adult Soft Tissue Sarcoma: A Prospective Observational Real-World Data

Introduction There is a lacuna of prospective studies on soft tissue sarcoma (STS) from the Indian subcontinent in published literature.

Objectives We conducted this study to describe the clinical profile and outcomes of STS in North India.

Materials and Methods This is a single-center, prospective, observational study conducted from October 2017 to September 2019. All consecutive patients aged ≥18 years with histopathological diagnosis of STS were enrolled. The study end points included overall response rate, progression-free survival (PFS), and overall survival (OS).

Results A total of 140 patients were included with a median duration of follow-up of 14 months (range: 1–25 months). The median age of patients was 45 years. The median duration of symptoms before diagnosis was 5 months (range: 1–18 months). The most common histopathologic subtype was undifferentiated pleomorphic STS (22%). Of 105 localized patients, 21 received neoadjuvant therapy with external beam radiotherapy and/or doxorubicin-based chemotherapy and reported partial response in 38% (8/21) of the patients; the remaining 62% (13/21) of the patients had stable disease. Neoadjuvant therapy resulted in nonsignificantly higher complete resection rates with relative risk of 2.37 (p = 0.19). Of the remaining 35 metastatic STS patients, 31 received chemotherapy and reported partial response in 39.1% (n = 9/23), stable disease in 30.4% (n = 7/23), and disease progression in 30.4% (n = 7/23) of the patients. For localized STS patients, 1-year disease-free survival (DFS) and OS rates were 87.6 ±3.5 and 95.3 ± 2.3%, respectively. The median OS for metastatic STS patients was 23.90 months (95% confidence interval [CI]: 7.43–40.36). Among metastatic STS, median OS was not reached for those who underwent curative resection versus 12.66 months (95% CI: 9.28–16.04) for those who received systemic therapy alone.

Conclusion Median age of 45 years is a decade earlier than seen in the Western population. Neoadjuvant therapy improved complete resection rates, though it was statistically nonsignificant. Curative resection among metastatic STS patients improves survival.

A Population-based Analysis of Lymph Node Metastasis in Extremity Soft Tissue Sarcoma: An Update

BACKGROUND

Soft tissue sarcomas (STSs) are mesenchymal tumors that may rarely metastasize to lymph nodes. This investigation sought to evaluate regional lymph node metastasis (RLNM) in extremity STS using a national cohort.

MATERIALS AND METHODS

This study was a retrospective review of the Surveillance, Epidemiology, and End Results database from 1975 to 2016. A Cox proportional hazards model was used to identify prognostic factors associated with disease-specific survival (DSS).

RESULTS

RLNM was present in 3.7% (n = 547) of extremity STS. The rate of RLNM was highest in rhabdomyosarcoma (26.7%), clear cell sarcoma (18.8%), epithelioid sarcoma (14.5%), angiosarcoma (8.1%), spindle cell sarcoma (5.0%), and synovial sarcoma (3.2%). The 5-year DSS probability without RLNM was 69% (standard error: 1.3%) compared to 26% (standard error: 3.6%) with RLNM (P < 0.001). For the historically high-risk extremity STS, advanced age (hazard ratio (HR), 1.036; 95% confidence interval (CI), 1.0-1.04; P < 0.001), higher grade tumors (HR, 1.979; 95% CI, 1.3-3.0; P < 0.001), tumor size greater than 10 cm (HR, 1.892; 95% CI, 1.3-2.7; P < 0.001), primary site surgery (HR, 0.529; 95% CI, 0.3-0.8; P = 0.006), distant metastasis (HR, 4.585; 95% CI, 3.0-6.8; P < 0.001), and RLNM (HR, 2.153; 95% CI, 1.3-3.5; P = 0.003) were each independent disease-specific prognostic factors.

CONCLUSIONS

The prognosis of RLNM in historically high-risk extremity STS is poor with a 5-year DSS of 26%. These data support a staging system of STS inclusive of nodal involvement and contribute to the growing body of evidence that characterizes the rates of RLNM in STS.