Clinical Outcomes and Prognostic Factors for Patients with Malignant Peripheral Nerve Sheath Tumour

Introduction. Few studies have described the characteristics and prognostic factors of patients with malignant peripheral nerve sheath tumour (MPNST). In this study, we retrospectively investigated the clinicopathological features, clinical outcomes, and prognostic factors of these patients. Patients and Methods. We recruited patients with MPNST who were treated at our institutions from 1991 to 2020. We collected and statistically analysed information on patient-, tumour-, and treatment-related factors. The median follow-up period was 61 months (range, 1–335.8 months). Results. A total of 60 patients (31 males, 29 females) with a median age of 55 years (range, 8–84 years) at initial diagnosis were included. The median tumour size was 7 cm (range, 1.6–30 cm) in the greatest dimension. The 5-year overall survival (OS) rate of all patients was 69.5%. Univariate analysis revealed that large-sized tumour, metastasis at diagnosis, and no surgery of the primary tumour were significantly associated with patients with worse OS. Multivariate analysis identified surgery of the primary tumour as an independent prognostic factor for improved OS. Among patients with localised disease at diagnosis who underwent surgery of the primary tumour at our institutions, the 5-year OS, local recurrence-free survival (LRFS), and metastasis-free survival (MFS) rates were 81.1%, 78.2%, and 70.3%, respectively. Univariate analysis revealed that positive surgical margin was significantly correlated with unfavourable OS and LRFS, and high grade was a poor prognostic indicator for MFS. Conclusion. Complete surgical resection with negative surgical margins is necessary for a successful MPNST treatment. Multidisciplinary management of MPNST with aggressive features is important for optimising patient outcomes.

Malignant peripheral nerve sheath tumour transformation of histological benign vestibular schwannoma after stereotactic radiosurgery in patients without neurofibromatosis

Stereotactic radiosurgery (SRS) poses a minimal but important risk for tumour transformation, typically occurring 8–10 years after the treatment. Malignant peripheral nerve sheath tumour (MPNST) is the most common tumour arising from a vestibular schwannoma treated with SRS, with only 14 cases previously reported. We present the fifteenth case and describe its evolution and clinical course. A 56-year-old man without a history of neurofibromatosis was diagnosed 9 years prior with a vestibular schwannoma. SRS to the residual tumour was given 3 months later. During the current hospitalisation, he was reoperated where histology confirmed a MPNST. All 15 MPNST cases were analysed, showing a 77% female predominance presenting a malignant transformation at a mean age of 51. The diagnosis was made at a mean time of 74 months after SRS. The mean survival time after diagnosis was 16 months. MPNST arising from benign vestibular schwannoma after SRS treatment is an uncommon but devastating complication.

Malignant peripheral nerve sheath tumour in an unusual location of the urinary bladder: case report and review of literature

Background Malignant peripheral nerve sheath tumour (MPNST) is a rare malignant soft tissue neoplasm of ectomesenchymal origin. They usually arise from a major or minor peripheral nerve branch or its sheath and also from somatic soft tissues. The most common sites of origin include the extremities and trunk but can sometimes arise an unusual site resulting in the demise of the patient before any intervention. Case presentation We report a case of 58-year-old male who presented with complaints of weight loss of a year duration, abdominal swelling of 10 months duration and easy fatigability of 3 weeks duration. Digital rectal examination revealed a huge firm mass 6 cm from the anal verge which was non-tender. Abdomino-pelvic ultrasound scan revealed an irregular heterogeneous mass in the posterior wall of the urinary bladder measuring 15.1cmx 14.0 cm with bilateral dilatation of the renal pelvi-calyceal system and ureters. His clinical condition continued to deteriorate while on hospital admission, and he died on the12th day of admission. Post-mortem examination showed a rough ovoid tumour mass firmly adherent to the posterior wall of the bladder with compression of both ureters. Histological and immunohistochemical analysis of the tumour revealed the diagnosis of a MPNST. The final anatomical diagnosis and cause of death was that of a malignant peripheral nerve sheath tumour of the urinary bladder with obstructive uropathy and severe sepsis. Conclusion MPNST can arise at unusual sites other than its common location in the extremities and the existence of neurofibromatosis may not be present. High index of suspicion of MPNST should be raised in rapidly growing painless tumour in and around a nerve tissue. Prompt radio-imaging with biopsy and expert immunohistochemical analysis of lesions will lead to early diagnosis and intervention. Molecular targeted therapies following surgery for MPNST should be developed to improve prognosis and patient outcomes.

Extradigital glomangiomyoma of the forearm mimicking peripheral nerve sheath tumour and thrombosed varicose vein

Extradigital glomus tumour is uncommon, little-known outside of its subungual location, and may present without its classic triad of tenderness, cold sensitivity and paroxysmal pain. Imaging is non-specific and diagnosis is often delayed, sometimes for years, leading to unnecessary morbidity. Surgical excision is the treatment of choice, although technique depends on case specifics. Histological subtypes depend on the relative prominence of glomus cells, vascular structures and smooth muscle. The vast majority of glomus tumours are benign. We highlight the importance of considering extradigital glomus tumours when generating differential diagnoses of an atypical painful lesion in a variety of clinical specialties.