Giant paravertebral myxoma

Abstract

The study design includes case report and clinical discussion. The objective was to describe a rare case of a giant intramuscular myxoma (IMM) presenting as a mass in the paravertebral muscles. Myxoma is a rare benign soft tissue tumour of mesenchymal origin. Although intramuscular presentation is common, they are rare in the paravertebral muscles and are characteristically \5 cm in length. We report the clinical and imaging features in a 70-year-old woman presenting with back pain, asymmetry of the waist and a mass in right paravertebral region. This was originally misdiagnosed as a juxtafacet synovial cyst after CT-guided biopsy. The mass was excised en bloc and sent for histology. This revealed a low-grade myxoid neoplasm with features of an IMM. The patient went on to make a complete recovery. To our knowledge, this is only the fifth case of paravertebral IMM reported in the literature and at approximately 15 cm in length may be the largest encountered in clinical practice.

Intramuscular Myxoma of the Tibialis Anterior Muscle : First Report in the English Literature

“…The clinical presentation of these lesions depends on their size and location and, as in this patient's case, they have generally been known to present as isolated lesions that are slow growing. These masses usually lie dormant for extended periods of time before suddenly enlarging [2]. They may, however, produce compressive symptoms on surrounding tissues and can occasionally be painful [7].…”

“…Myxomas lack a classical presentation as they vary depending on size and location. Yet, in almost all cases described, they are reported to be slow growing masses that rapidly enlarge [2]. These myxomas also lack unique radiological findings, necessitating a biopsy for their diagnosis, when indicated.…”

Radiological Characteristics and Management of Intramuscular Myxoma of the Temporal Muscle: Case Report

“…Most lesions have focal areas of hypercellularity that are visible as areas of heterogeneous internal enhancement with gadolinium, which might cause further confusion with malignant tumors. 5 , 8 , 12 , 13) In addition, a fat rim separating the tumor from adjacent muscle might be evident on MRI. Angiographic examination reveals a poorly vascularized soft tissue mass.…”

“… 8 , 12) Therefore, soft tissue sarcomas tend to grow more rapidly and reveal heterogeneous variable signal intensity, ill-defined margins along with evidence of invasion of adjacent structures, and intense diffuse enhancement on MRI images. 5) Furthermore, rich vascular network on angiography is the most conclusive difference from intramuscular myxoma. 14) …”

“…Intramuscular myxoma is mostly seen in large skeletal muscles and rare in the head and neck. 1 , 3 – 5) This tumor sometimes gets associated with fibrous dysplasia in the same anatomical region, which is known as Mazabraud's syndrome. 6) Intramuscular myxoma typically presents as a slow-growing painless mass, but symptoms might occur from compression of the surrounding structures.…”