Aggressively recurrent infantile myofibroma of the axilla and shoulder girdle

Diverse presentation and tailored treatment of infantile myofibromatosis: A single-center experience

BACKGROUND

Infantile myofibromatosis (IM) is a rare benign fibrous tumor with diverse clinical presentations and treatments, such as watchful waiting, surgical excision, and low-dose chemotherapy.

PROCEDURE

Clinical presentation and tailored treatment of five infants with solitary and generalized IM are described, together with a review of the literature.

RESULTS

Three patients underwent total-body magnetic resonance imaging (MRI) at diagnosis and during follow up, which revealed disease extension that aided in designing treatment. Visceral involvement included central nervous system, cardiac, gastrointestinal, muscle, bone, and subcutaneous tissue lesions. The patient with the solitary form of IM was followed up without treatment and had spontaneous improvement. Patients with the multicentric form received intravenous low-dose methotrexate and vinblastine chemotherapy. One patient who received oral methotrexate due to cardiac involvement and unfeasible central line access had excellent results. Recurrence was successfully treated by the same methotrexate and vinblastine regimen as that administered at diagnosis.

CONCLUSIONS

We suggest screening all patients with one or more IM lesions by means of total body MRI due to its inherent superior soft tissue resolution. Total-body MRI may also be used for routine follow up. Oral methotrexate can be administered successfully in patients that lack central line access, and recurrent lesions can be treated with the same chemotherapeutic combination as that given at diagnosis. Long-term follow up is needed, since recurrence could appear years after initial presentation of the disease.

Myofibroma/myofibromatosis: MDCT and MR imaging findings in 24 patients with radiological-pathological correlation

Background

The aim of this study was to characterize the radiological features of myofibroma on multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) and correlate the imaging findings with pathologic features.

Methods

The radiological findings of 24 patients with 29 myofibromas were retrospectively reviewed. All images were evaluated with emphasis on density, signal intensity, hypointense area, and enhancement, correlating these with pathologic findings.

Results

On plain MDCT scan, 4(26.7%) tumors were homogeneous isodensity, 4(26.7%) tumors were heterogeneous hyperdensity, and 7(46.7%) tumors were heterogeneous hypodensity. On contrast-enhanced MDCT scan, all tumors (9/9) showed heterogeneous enhancement with moderate in 3(33.3%) and marked in 6(66.7%) tumors, and their enhancements were higher compared to adjacent skeletal muscle (P = 0.0001). On MRI, heterogeneous slight hyperintensity, homogeneous slight hyperintensity, and heterogeneous hypointensity on T1-weighted imaging (T1WI) were observed in 14(82.3%), 1(5.9%) and 2(11.8%) tumors, respectively. On T2-weighted imaging (T2WI) and fat-suppressed (FS) T2WI, all tumors demonstrated heterogeneous hyperintensity. All tumors showed heterogeneous marked enhancement on FS contrast-enhanced T1WI. On T1WI, T2WI, FS T2WI, and FS contrast-enhanced T1WI, irregular strip or/and patchy hypointensities were found in 16(94.1%), 12(100%), 17(100%) and 17(100%) tumors, respectively, and pseudocapsule was seen in 5(29.4%) tumors. The hypointensities and pseudocapsule on MRI were exactly corresponding to pathological interlacing collagen fibers and fibrosis. The age of the recurrent group was lower than that of the non-recurrent group (P = 0.001) and the tumors without pseudocapsule were more likely to recur than those with pseudocapsule (P = 0.034).

Conclusion

Myofibromas are characterized by heterogeneous density or signal intensity, with moderate or marked enhancement. The hypointensities and pseudocapsule on MRI may be helpful in diagnosis, and the absence of pseudocapsule and younger age may be risk factors for tumor recurrence.

Solitary intraosseous myofibroma of the ilium in an adult patient: A case report and literature review

BACKGROUND

Myofibroma is a rare benign tumor typically occurring in the skin and subcutaneous tissues of the head and neck in infants and young children. The incidence of solitary intraosseous and adult myofibroma is extremely low. Although there have been a few reported cases of solitary intraosseous myofibroma in adult patients, most of these cases involved the craniofacial bones.

METHODS

We present the case of a 64-years-old woman presenting with minimal pain of the right buttock and groin.

RESULT

Radiographs and computed tomography showed a huge tumor spreading around the ilium, and non-uniform calcifications were noted inside the tumor. Iliac tumor biopsy was conducted, and intraosseous myofibroma was suspected. We performed surgical resection of the mass, and a final diagnosis of myofibroma with metaplastic bone production was made.

CONCLUSION

We have presented an extremely rare case of solitary intraosseous myofibroma in an adult patient.

A Distinctive Genomic and Immunohistochemical Profile for NOTCH3 and PDGFRB in Myofibroma With Diagnostic and Therapeutic Implications

Introduction. Myofibromas are rare tumors of pericytic lineage, typically affecting children, and are sometimes aggressive. A subset of sporadic and familial myofibromas have activating variants in PDGFRB. The relationship of myofibroma and PDGFRB to the NOTCH pathway has not yet been described. Methods. Ten myofibroma cases were sequenced with a targeted panel of 447 genes, including copy number variation and selected fusions. Immunohistochemical analysis of total NOTCH3 and activated NOTCH3 was assessed for all 10 myofibroma cases, and a series of histologic mimics (n = 20). Results. Alterations identified by next-generation sequencing included PDGFRB sequence variants in 8/10 cases (80%), a NOTCH3 variant in 1/10 cases (10%), and a NOTCH2 variant in 1/10 cases (10%). All 10 cases also showed a pattern of low-amplitude (1.5- to 2-fold) copy number alterations including gains in PDGFRB and NOTCH3. Ten of 10 myofibromas (100%) showed cytoplasmic staining for total NOTCH3 and 9 of 10 cases (90%) showed nuclear staining for activated NOTCH3. Within the control cohort of histologic mimics, 3 of 3 nodular fasciitis cases (100%) were positive for activated and total NOTCH3, and the remaining 17 cases were negative for pan NOTCH3, while 3 of 3 desmoid-type fibromatosis cases (100%) showed patchy weak nuclear staining for activated NOTCH3. Discussion. Our findings suggest a common pathway of PDGFRB/NOTCH3 activation in myofibromas, even in cases that lack PDGFRB sequence variants. These results support the pericytic lineage of myofibroma. Identification of the characteristic genomic alterations or immunohistochemical staining pattern may facilitate a difficult pathologic diagnosis, and support the use of targeted treatments.

Solitary infantile myofibromatosis in the bones of the upper extremities: Two rare cases and a review of the literature

Infantile myofibromatosis (IM) is the most common fibrous tumor of infancy. IM may arise in a solitary or multicentric form, with similar histopathological findings, however, the clinical features and prognoses may vary. The solitary form tends to occur predominantly in males and is typically observed in the dermis, subcutis or deep soft tissues. The reported incidence of solitary osseous myofibromatosis is rare. Furthermore, the majority of solitary IM cases of the bone occur in the craniofacial bones, while the occurrence of solitary osseous myofibromatosis on the extremities has been sporadically reported. The present study describes two cases of solitary IM involving the bones of the upper extremities in females who were over two years old. The cases show unusual symptom presentation and the tumor origin is in a rarely observed location. The study discusses the clinical, radiological and pathological features, in addition to the previously described etiology, prognosis and treatment options for this condition.

Extraskeletal chondroma: another diagnostic possibility for a soft tissue axillary mass in an adolescent

Extraskeletal chondroma is a benign cartilaginous tumor that occurs predominantly in the soft tissues near small joints of the hands and feet. There are rare reports of the lesion in other sites, such as the head, neck, trunk, oral cavity, larynx, and pharynx. We present a case of an axillary mass in a 15-year-old girl who underwent MRI examination and resection, with the ultimate diagnosis of an extraskeletal chondroma, in order to expand the differential diagnosis of an axillary soft tissue mass in an adolescent.