Para-articular and intra-articular soft tissue lesions: Radiologic-pathologic correlation.

Articular masses comprise various disease entities including benign or malignant proliferative processes and other non-neoplastic processes such as infection, deposition diseases, vascular malformations, and other lesions. Many diseases that lead to intra-articular or para-articular masses have distinct imaging features, particularly on MRI. Radiologists can localize masses to the joint space by knowing the articular anatomy and can reach a suggested diagnosis by looking at precise imaging findings. In this review article, we first define the concept of articular space (intraarticular, para-articular) and the normal joint anatomy and histology. We provide a general and comprehensive approach for evaluation of articular lesions on MRI. We then describe specific imaging and histologic features of typical benign and malignant soft tissue articular neoplasms and some non-neoplastic mimickers; and provide a radio-pathologic correlation of the different described entities.

Idiopathic Granulomatous Mastitis, Erythema Nodosum, and Polyarthritis.

Idiopathic granulomatous mastitis (IGM) is an inflammatory-mediated rare disease that can be linked to rare manifestations. Erythema nodosum (EN) and polyarthritis, seen in a multitude of autoinflammatory and autoimmune diseases, have been rarely linked to IGM. Despite the cause of IGM being unclear, Corynebacterium infections are thought to play a role in the pathophysiology of IGM. Unusually, IGM has a relapsing and remitting course, which also applies to its systemic manifestations. As such, we present a case of IGM in a middle-aged lady who was initially thought to have Corynebacterium-containing unilateral abscesses for which drainage was performed. However, several abscesses devoid of bacterial growth started recurring, and the disease course was complicated by EN and polyarthritis. IGM, EN, and polyarthritis eventually resolved and were managed with symptomatic treatment.

Eosinophilic Orbital Myositis Superseding Ocular Myasthenia.

Various muscles can be involved in idiopathic eosinophilic myositis (IEM), with the ocular muscles being notably affected. Ocular eosinophilic myositis is a rare condition that typically affects the rectus muscles. A tissue biopsy stands as the gold standard for diagnosis. Different subtypes exist based on the extent of eosinophilic infiltration. Limited data is available about treatment, although glucocorticoids have shown successful outcomes. We present the case of a 60-year-old man who, a few years after being diagnosed with ocular myasthenia gravis, was diagnosed through a tissue biopsy with ocular eosinophilic myositis. Treatment with oral glucocorticoids significantly improved his symptoms.

Sarcoidosis Mimicking a Malignant Metastatic Disease.

Sarcoidosis can have pulmonary and extrapulmonary clinical manifestations depending on the organ of involvement. Because multiple organs are involved by the disease, sarcoid can mimic metastatic diseases. Whenever clinical and radiological clues of metastasis are present, differentials other than cancer should not be missed. Herein, we present a case of a middle aged gentleman who presented to the oncology clinic for 1-month history of low back pain associated with a dry cough along with radiological findings of metastatic disease involving the lungs, liver, lymph nodes, axial spine, and adrenal gland. A biopsy of the liver lesion showed non-caseating granuloma. Elevated blood levels of angiotensin-converting enzyme confirmed the diagnosis of sarcoidosis.

Frequency and mutational spectrum of PIK3CA gene mutations in breast cancer patients: Largest and first report from Lebanon.

The PIK3CA pathway is one of the most frequently altered pathways in human cancers, especially in breast cancer with approximately 40% of HR+/HER2- advanced breast cancer cases exhibiting mutations in the PIK3CA gene. While the mutations can occur across the entire gene, the most common are observed in exon 9 corresponding to the helical domain, and in exon 20 encompassing the kinase domain. This study constitutes the first attempt at determining the frequency and mutational spectrum in Lebanese breast cancer patients. For this purpose, DNA samples from 280 breast cancer patients from across Lebanon were screened for PIK3CA mutations using the Therascreen® PIK3CA RGQ Real-time PCR assay. In line with previous reports, 38.57% of cases were positive for at least one PIK3CA mutation, among which approximately 59% were in exon 9 and 37% in exon 20. However, PIK3CA mutations are breast cancer are heterogeneous whereby 20% of known PIK3CA mutants might not be detected by compact PCR based assays. Thus, the adoption of comprehensive Next Generation Sequencing based panels to decipher the complete clinical, molecular and immunohistochemical profile of breast cancer tumor requires further investigation.

Spinal intradural extramedullary granular cell tumor.

Background: Granular cell tumors (GCTs) are uncommon peripheral nerve sheath tumors of Schwann cell origin that may occur throughout the body. However, they rarely occur in the spinal canal. Case Description: A 49-year-old male presented with burning sensation in the left knee. The MRI of the lumbar spine showed an L3-L4 intradural extramedullary tumor. Complete surgical resection was successfully performed and the L3 root burning improved. Histopathologically, the lesion proved to be a benign GCT. Conclusion: Spinal GCTs are rare benign tumors that may be found in an intradural extramedullary location in the spine. The preferred treatment is complete surgical resection as subtotal/partial resection may result in recurrence warranting radiation therapy.