Multicentric extra-abdominal desmoid tumors arising in bilateral lower limbs

Multifocal Desmoid-Type Fibromatosis: Case Series and Potential Relationship to Neuronal Spread

Multifocal desmoid-type fibromatosis (DTF) is very rare and usually regional. We report three cases that initially appeared to be multifocal, but subsequent detailed imaging revealed unsuspected tracking along nerves in two cases. This neural spread is reminiscent of neuromuscular choristoma (NMC), a rare developmental lesion in which mature skeletal muscle cells, or rarely smooth muscle cells, infiltrate and enlarge peripheral nerves. NMC is frequently associated with DTF. These two cases suggest that DTF spread along nerves and appeared as distinct multifocal lesions while actually being contiguous. The third case was felt to represent true multifocal tumor development, possibly due to tumor seeding at the time of chest surgery. The relationship of DTF to NMC is discussed.

Large Multicentric Synchronous Extra-Abdominal Fibromatosis of the Leg and Foot: A Case Report

Extra-abdominal fibromatosis is an uncommon, benign locally aggressive fibrous soft-tissue tumor that usually occurs in the shoulders, chest wall, back, thigh, and head and neck affecting the young adult population. It is commonly located in the subcutaneous tissue and may infiltrate the adjacent skeletal muscles. We hereby report a rare case of a large extra-abdominal fibromatosis of the leg and foot in a 38-year-old woman. The patient presented with a large voluminous lesion clinically and on imaging, which was difficult to diagnose. Magnetic resonance imaging (MRI) was very helpful in diagnosing the lesion. It revealed a large relatively well-defined, lobulated hypointense mass in the posterior compartment of the leg with extension into the lower thigh and foot with local infiltration into the gastrocnemius and soleus muscles. An incisional biopsy was performed, and the mass was diagnosed on pathological examination as a spindle-shaped fibroblast proliferation suggesting extra-abdominal fibromatosis.

The Clinical Features of Multicentric Extra-abdominal Desmoid Tumors

BACKGROUND

Extra-abdominal desmoid tumors often occur in the necks, shoulder, chest wall, back, arm, buttock, thigh and leg. Multicentric extra-abdominal desmoids are rather rare and seem to have other clinical features. The aim of our study was to investigate clinical features, especially multicentric occurrence of extra-abdominal desmoid tumors.

PATIENTS AND METHODS

A total of 135 patients diagnosed with extra-abdominal desmoid were enrolled in this study from January 2005 to December 2019 at the Cancer Institute Hospital of The Japanese Foundation for Cancer Research. The operative procedure was principally wide excision. The clinicopathological factors [e.g., age, gender, pain, restriction of range of motion (ROM), tumor site, tumor size, surgical margin, multicentric occurrence, local recurrence, tumoral regression] were collected and assessed by univariate analysis. We assessed how multicentric occurrence influenced clinicopathological factors of desmoid tumors.

RESULTS

The median follow-up was 39.9 months (range=0.29-259 months). Among 135 patients, 20 had multicentric occurrence. Multicentric extra-abdominal desmoids occurred in the neck in six cases, shoulder in four, chest wall in three, back in three, thigh in two and leg in two. In the case of multicentric occurrence on thighs and legs, tumors arose not in the anterior compartment but in the posterior compartment. Univariate analysis showed association of multicentric extra-abdominal desmoids with high local recurrence (p=0.0003), restriction of ROM (p=0.0012) and tumor size larger than 5 cm (p=0.04) but surgical margins were not correlated with local recurrence (p=0.37).

CONCLUSION

Surgery should be performed in those who have severe pain or restriction of ROM. A 'Wait and see' policy is a first-line management, especially for those with multicentric extra-abdominal desmoids.

Bilateral multifocal lower extremity localized soft tissue amyloidomas: case report with ultrasonographic characterization

Amyloidosis may be acquired or hereditary and consists of multiple disease processes characterized by the abnormal deposition of extracellular fibrillary protein aggregates. The presentation of amyloidosis is varied, ranging from an isolated, focal deposition to systemic disease. While systemic involvement is common, a rare entity known as amyloidoma or tumor amyloidosis may also occur. The 75-year-old female in this case presented with slowly growing multifocal bilateral lower extremity masses and was ultimately diagnosed with localized amyloidomas in the absence of chronic illness or systemic disease. This case report includes a description of the sonographic features of localized extremity amyloidoma that, to the best of our knowledge, have not yet been described in the literature. Awareness of the sonographic features, and this unique presentation of multifocal soft tissue extremity amyloidomas will allow for this rare diagnosis to be included in a limited differential diagnosis.