Natural speed of growth of untreated soft-tissue sarcomas: A dimension-based imaging analysis

Growth Rate and Outcomes in Locally Recurrent Extremity and Truncal Soft Tissue Sarcoma

Importance

Improved prognostic tools are needed for patients with locally recurrent extremity or truncal soft tissue sarcoma (STS).

Objective

To examine the association between average local recurrence (LR) growth rate and outcomes following resection of locally recurrent extremity or truncal STS.

Design, Setting, and Participants

This retrospective cohort study used a prospectively maintained database from a single high-volume tertiary sarcoma referral center in the US to identify patients 16 years of age or older who underwent repeat resection of a locally recurrent extremity or truncal STS between July 1, 1982, and December 31, 2021. Patients with atypical lipomatous tumors, desmoid tumors, dermatofibrosarcoma protuberans, angiosarcomas, and prior or synchronous distant recurrence were excluded. Data were analyzed from November 1, 2022, to June 17, 2024.

Exposure

Average LR growth rate, defined as the sum of recurrent tumor maximal diameters divided by the disease-free interval after index operation.

Main Outcomes and Measures

The primary outcomes were cumulative incidences of disease-specific death (DSD), with death from other causes as a competing risk, and second LR, with death from any cause as a competing risk.

Results

The study cohort included 253 patients (median [IQR] age, 64 [51-73] years; 140 [55.3%] male). The 5-year cumulative incidence of DSD after repeat resection was 29%. Multivariable analysis indicated that LR growth rate (hazard ratio [HR], 1.12 [95% CI, 1.08-1.18]; P < .001), younger age (HR, 0.98 [95% CI, 0.97-0.99]; P = .002), R1 or R2 margins (HR, 1.71 [95% CI, 1.03-2.84]; P = .04), high LR grade (HR, 2.90 [95% CI, 1.17-7.20]; P = .02), and multifocality (HR, 2.92 [95% CI, 1.70-5.00]; P < .001) were independently associated with higher incidence of DSD. Using the minimum P value method, the optimal cutoff for growth rate was found to be 0.68 cm/mo. Patients with values above this cutoff had higher 5-year incidences of DSD following repeat resection (63% vs 19%; permutation test P < .001) and higher amputation rates (19% vs 7%; P = .008). Only R1 margins were independently associated with higher incidence of second LR (HR, 1.81 [95% CI, 1.19-2.78]; P = .006).

Conclusions and Relevance

In this cohort study of patients undergoing resection of a locally recurrent extremity or truncal STS, LR growth rate was independently associated with DSD. These findings suggest that patients with growth rates higher than 0.68 cm/mo who undergo LR resection may have high disease-specific mortality and amputation rates and should be considered for perioperative systemic therapy.

Role of Imaging in Initial Prognostication of Locally Advanced Soft Tissue Sarcomas

BACKGROUND

Although imaging is central in the initial staging of patients with soft tissue sarcomas (STS), it remains underused and few radiological features are currently used in practice for prognostication and to help guide the best therapeutic strategy. Yet, several prognostic qualitative and quantitative characteristics from magnetic resonance imaging (MRI) and positron emission tomography (PET) have been identified over these last decades.

OBJECTIVE

After an overview of the current validated prognostic features based on baseline imaging and their integration into prognostic tools, such as nomograms used by clinicians, the aim of this review is to summarize more complex and innovative MRI, PET, and radiomics features, and to highlight their role to predict indirectly (through histologic grade) or directly the patients' outcomes.

Soft-tissue sarcoma in adults: Imaging appearances, pitfalls and diagnostic algorithms

This article provides an overview of the current knowledge regarding diagnostic imaging of patients with soft-tissue sarcomas, which is a heterogeneous group of rare mesenchymal malignancies. After an initial contextualization, diagnostic flow-chart based on initial radiological findings of soft-tissue masses (with specific focus on adipocytic soft-tissue tumors [STTs], hemorragic STTs and retroperitoneal STTs) are provided considering relevant results from novel researches, guidelines, and experts' viewpoints, with the aim to help radiologists and clinicians in their practice. Particularly, the central place of sarcoma reference centers in the diagnostic and therapeutic management is highlighted, as well as the pivotal role that radiologists should play to correctly identify patients with soft-tissue sarcoma at the initial stage of the disease. Indications and methods for performing imaging-guided biopsies are also discussed, as well as clues to improve soft-tissue sarcoma grading with conventional and quantitative imaging.