A Rare Case of Left Atrial Primary Malignant Nerve Sheath Tumour: Case Report

MO002 

Case Video Submission 

Alicia Chia (1), Philip Pang (2)

(1) National Heart Centre Singapore, Singapore, (2) National Heart Centre Singapore, Singapore, NA

Alicia Chia    -  Contact Me
National Heart Centre Singapore

Philip Pang    -  Contact Me
National Heart Centre Singapore

Alicia Chia    -  Contact Me
N/A

Objective:
Malignant peripheral nerve sheath tumor (MPNST) is a rare soft tissue sarcoma, accounting for approximately 2% of all sarcomas. It has a high rate of local recurrence and metastatic dissemination. Amongst all phenotypes of malignant primary cardiac tumors, MPNST is exceedingly rare with an incidence of 0.75% of all cardiac tumors. To date, only a handful of cases have been reported in the literature. Due to its scarcity, little is known about this disease entity and its optimal course of treatment. The current preferred course of treatment is by full surgical resection of the tumor, followed by adjuvant radiotherapy and chemotherapy.

Case video summary:
We report a unique case of a 50-year-old, previously healthy man, presenting with symptoms of congestive heart failure. Investigations revealed a large left atrial (LA) mass prolapsing across the mitral valve into the left ventricle during diastole, resulting in mitral inflow obstruction.

The patient underwent successful surgical resection of the left atrial tumor the next day. Intraoperative evaluation showed an atypical location of the mass arising from the posterolateral wall of the LA, extending into the left pulmonary veins and left atrial appendage. This heightened our suspicion of a malignant cardiac neoplasm. Histological examination confirmed the diagnosis of MPNST. The patient unfortunately had distant metastasis to the brain and vertebral body prior to commencement of chemotherapy.

Conclusions: Despite current aggressive multimodal therapy, the prognosis of patients with MPNST remains dismal with a mean survival ranging from 3 months to 1 year. Even after optimal radical resection, a significant proportion of patients (40-70%) develop local recurrence or distant metastases, usually within 1 year. Available therapies offer very limited benefits to patients with MPNST. Further research is required for new therapies.

Challenging Clinical Cases