Tomoki Nakamura

Background/Objectives: The aim of this study was to review the clinical course of schwannoma in 176 patients and elucidate the clinical outcome in a patient who received surgical treatment and one who did not. Methods: Between August 2006 and December 2021, 176 patients with solitary and sporadic schwannomas were enrolled in our institution. There were 94 men and 82 women, with a mean age of 57 years. During follow-up, 76 patients received surgical treatment, and the remaining 100 did not. Results: The mean tumor size at initial presentation was 30 mm. The major tumor locations were the thigh, lower leg, upper arm, and forearm. The major nerves affected by the schwannoma were the intramuscular branch, sciatic nerve, and ulnar nerve. At least one symptom in addition to a palpable mass was observed in 133 patients (76%). The variables that indicated surgical treatment were tumor size at initial presentation, age, and any other existing symptoms. After surgery, pain-related symptoms including pain, irradiated pain and tenderness were resolved completely in 42 of 44 patients (95%) who had displayed them preoperatively. Neurological deficit was observed in 26 patients (34%). Among the 26 patients with neurological deficit, neurological sensory deficit was observed in 23 patients, and the remaining three had sensory and motor deficits. Multivariate analysis showed that patients with major nerve schwannoma, those with paresthesia preoperatively, and those who developed preoperative symptoms and had undergone surgery had a higher risk of the development of postoperative neurological deficit. Conclusions: Our findings should be considered while planning surgery and obtaining informed consent.

Soft tissue sarcoma (STS) is a rare and heterogeneous disease, which can result in surgeons not considering STS as a differential diagnosis when they encounter a lump. However, unplanned excision (UE) often occurs in nonspecialized sarcoma centers. Before re-excision (RE) after UE, radiological examinations such as magnetic resonance imaging (MRI) should be performed to determine the surgical margin and conduct a pathological evaluation of the UE. However, differentiating between residual tumor and postsurgical changes remains challenging because of the presence of postoperative edema, hematoma, and seroma on MRI. Propensity score matching analysis showed that patients with STS who underwent RE after UE did not have higher mortality or local recurrence rates than those who underwent planned excision (PE), while RE often requires reconstruction procedures. From the patient’s perspective, one operation (PE) is better than two (UE and RE) because it reduces hospital stays and time away from work. Continuous education about STS is necessary for all surgeons to reduce the incidence of UE.