Regional Lymph Node Macroscopic Metastases in Sarcoma Linked With Poor OS Outcomes

The presence of macroscopic metastases in regional lymph nodes is found to be related to poor survival outcomes in patients with sarcoma, according to a retrospective results of a single-institution study that were presented during the virtual 2020 ESMO Congress.

Findings showed that in patients with lymph node metastases that was confirmed via therapeutic lymph node dissection (TLND), the median overall survival (OS) was 18 months (95% CI, 17-48) compared with the 70 months in those with nonmetastatic and micrometastatic nodal involvement (HR, 4.6; 95% CI, 2.1-9.7; P <.001).

In sarcomas, nodal involvement generally correlates with a similar poor prognosis as distant metastases. However, there are limited data with radical treatment in patients with sarcoma who have resectable nodal metastases.

In the single-center trial, conducted out of the Maria Sklodowska-Curie National Research Institute of Oncology in Warsaw, Poland, investigators sought to access the outcomes of patients with sarcoma who underwent sentinel lymph node biopsy (SLNB) and TLND for regional lymph node metastases. Electronic health records were reviewed of 64 patients treated at the center between 1996 and 2018 who underwent treatment; therapeutic lymph node dissection was performed for palpable nodal metastases and a positive SLNB.

All histopathological diagnoses were confirmed by a trained pathologist in sarcoma assessment. For patients lost to follow-up at the institution, survival status and date of death were retrieved from the Polish National Cancer Register. OS data was determined from the time of radical resection of involved lymph nodes to the time of death. Additionally, Kaplan-Meier estimator with the log-rank test, as well as Cox’s proportional hazard model, were both used in the statistical analysis, with P <.05 determined as value of significance. 

Thirty-seven of the patients were male, and the median age was 35 years (range, 25-46). Overall, the population included those with epithelioid sarcoma (n = 24), clear cell sarcoma (n = 21), synovial sarcoma (n = 12), and rhabdomyosarcoma (n = 7).

At a median follow-up period of 66 months, 33 cases had undergone SLNB, and 12 were found to be positive. This comprised 6 patients with epithelioid sarcoma, 3 with clear cell sarcoma, 2 with rhabdomyosarcoma, and 1 with synovial sarcoma. Eleven of 12 patients with a positive SLNB, and 37 patients with resectable clinically detected nodal metastases underwent TLND.

No nodal involvement was detected in 21 cases who were SLNB negative, and micrometastatic nodal involvement was found in 9 cases with a positive SLNB and a negative TLND. Positive TLND was reported in 34 cases.

Results also showed that OS was not significantly different between cases with nonmetastatic and micrometastatic nodal involvement, which was estimated to be 70 months (95% CI, 54–not available).

When OS was evaluated by nodal status, patients with a negative SLNB had the longest outcomes at 0 years (n = 21), 1 (n = 20), 2 (n = 16), 3 (n = 14), 4 (n = 8), 5 (n = 5), and 6 years (n = 1). In patients with positive TLND, the number of patients alive at 0, 1, 2, 3, 4, 5, and 6 years were 34, 24, 11, 6, 3, 1, and 1, respectively. In those with positive SLNB, there were 9 patients alive at 0 years, 8 alive at 1 year, 8 at 2 years, 4 at 3 years, 3 at 4 years, 3 at 5 years, and 1 at 6 years.

Survival was also compared across histology subtypes in those with nodal involvement, with the rhabdomyosarcoma subgroup having the shortest survival outcomes; no patients were alive at 3 years (P = .92). At 6 years, 1 patient with epithelioid sarcoma and 1 with synovial sarcoma were alive.

The authors concluded that early detection of lymph node metastases via SLND across sarcoma subtypes, specifically ones identified at having frequent lymph node involvement, could improve efficacy and survival outcomes to treatment.

Reference

Teterycz P, Czarnecka AM, Szmajdzińska A, et al. Prognostic role of regional lymph node metastases in soft tissue sarcomas. Presented at: 2020 ESMO Congress; September 19-21, 2020; virtual. Abstract 1661P.