Preoperative Factors Associated with Infiltrative Histologic Growth Patterns in Extremity Soft Tissue Sarcoma

Abstract

Soft tissue sarcoma (STS) with an infiltrative histologic growth pattern, when compared to STS with an expansile pattern, may pose difficulties in local control. Preoperative assessment of the presence of infiltrative histologic growth pattern would be helpful in deciding treatment strategies. A review of 144 patients who underwent surgery for extremity STS was performed. Microscopically, the histologic growth pattern was defined as infiltrative if the penetration of the tumor cells into the surrounding tissue was observed. Possible clinicopathologic factors that might be associated with infiltrative histologic growth pattern were investigated with regard to patient demographics, tumor characteristics, and MRI findings. Of the 144 tumors, 71 (49%) showed infiltrative histologic growth pattern. On multivariate analysis, histological subtypes other than liposarcoma (OR = 4.57, p = 0.02) and infiltrative border on MRI (OR = 2.48, p = 0.01) were independent factors associated with infiltrative histologic growth pattern. Predictive index based on these two factors showed a significant improved accuracy (ROC-AUC = 0.647) for predicting infiltrative histologic growth pattern compared to either factor alone. Our data suggests that liposarcoma histology and tumor border on MRI can predict histologic growth pattern in extremity STS.

Does the primary soft-tissue sarcoma configuration predict configuration of recurrent tumors on magnetic resonance imaging?

“…Other previously described morphological patterns are surgical margins, signal intensity, or peritumoral characteristics (28,30,31). Infiltrative histologic growth patterns are also associated with poor oncologic outcome (6). In our study, streaky and polycyclic/multilobulated recurrences mainly occur with infiltrative borders, while ovoid/nodular recurrences mostly present well-defined.…”

“…Accordingly, ovoid/nodular and streaky recurrences are mainly homogeneous, while polycyclic/multilobulated recurrences commonly present with a heterogeneous appearance. Tumor size is also often regarded as a risk factor for LR (20,32,33), but was recently described as insignificantly in the correlation to histological growth pattern (6). Other previously described morphological patterns are surgical margins, signal intensity, or peritumoral characteristics (28,30,31).…”

“…STS can develop anywhere in the body, but the primary site of STS remains the extremities (4,5). Local recurrences (LR) are frequently observed after STS resection and are associated with different factors, for example, positive postoperative margins or infiltrative histologic growth (6). LR are discovered in about 5%-35% of patients with STS (7).…”

On diagnosing Soft Tissue Sarcomas; an editorial

“…These tumors include a vast variety of histological types that are often distinctive in incidence patterns and possible clinical outcome. [1] STS comprise 1-5% of all malignancies in adults [2] with an estimated 12,390 new cases in 2017 in the USA [3]. However, the past two decades have been a significant improvement in prognosis.…”