Rapid Classification of Sarcomas Using Methylation Fingerprint: A Pilot Study.

Sarcoma classification is challenging and can lead to treatment delays. Previous studies used DNA aberrations and machine-learning classifiers based on methylation profiles for diagnosis. We aimed to classify sarcomas by analyzing methylation signatures obtained from low-coverage whole-genome sequencing, which also identifies copy-number alterations. DNA was extracted from 23 suspected sarcoma samples and sequenced on an Oxford Nanopore sequencer. The methylation-based classifier, applied in the nanoDx pipeline, was customized using a reference set based on processed Illumina-based methylation data. Classification analysis utilized the Random Forest algorithm and t-distributed stochastic neighbor embedding, while copy-number alterations were detected using a designated R package. Out of the 23 samples encompassing a restricted range of sarcoma types, 20 were successfully sequenced, but two did not contain tumor tissue, according to the pathologist. Among the 18 tumor samples, 14 were classified as reported in the pathology results. Four classifications were discordant with the pathological report, with one compatible and three showing discrepancies. Improving tissue handling, DNA extraction methods, and detecting point mutations and translocations could enhance accuracy. We envision that rapid, accurate, point-of-care sarcoma classification using nanopore sequencing could be achieved through additional validation in a diverse tumor cohort and the integration of methylation-based classification and other DNA aberrations.

Modified Transhumeral Amputation: A Case Report.

CASE: A 7-year-old boy presented with osteosarcoma of the ulna that required a transhumeral amputation. The patient completed neoadjuvant chemotherapy before surgery. To prevent bone overgrowth and improved prosthetic fitting, a modified amputation was performed with acute shortening and distal epiphysis preservation. CONCLUSION: In this modified amputation, bone overgrowth was not seen and repeated surgeries for stump shaping were prevented. The modified technique enabled length for the prosthetic elbow and a wide stump for better fitting. In cases of transhumeral amputation in children, the modified technique should be considered.

Paraneoplastic syndrome due to angiomatoid fibrous histiocytoma: a known presentation of an uncommon diagnosis in a rare site and age.

A woman in her 70s presented with a small subcutaneous retrosacrococcygeal mass and a history of elevated erythrocyte sedimentation rate present for several years. It was misdiagnosed as an inflammatory process of unclear origin. She underwent further investigation with the appearance of weight loss and weakness. A sacrococcygeal mass was noted on CT scan. A core needle biopsy was inconclusive for chordoma versus myoepithelioma. Wide surgical resection of the tumour including the coccygeal bone was performed. Following surgery, all the systemic symptoms resolved with normalisation of inflammatory markers. The pathological examination showed a relatively circumscribed multinodular myxoid tumour with lymphatic tissue cuff. Pan-sarcoma fusion analysis detected an EWSR1 (Exon7)-CREB1 (Exon7) fusion gene. The lesion was diagnosed as angiomatoid fibrous histiocytoma with paraneoplastic syndrome presentation of several years' duration.

Knee intra-articular extraskeletal aneurysmal bone cyst: a case report and review of literature.

Aneurysmal bone cyst (ABC) is a benign locally destructive lesion that usually developed in the bone cavity of bones, less commonly on the surface of cortical bones and very rarely develop outside the bone. There are only 35 reports of extraskeletal aneurysmal bone cyst (ESABC) in the English literature. We report a case of a 12-year-old female with no history of trauma who presented with knee pain. Imaging studies revealed an infrapatellar mass that was fast to calcify during a period of 3 months. MRI showed high T2 center, low T1 signal, and heterogenic enhancement with a rim of low intensity consistent with calcified boarders surrounded by severe soft tissue edema. The lesion was surgically excised, and a histological examination revealed an aneurysmal bone cyst possibly arising within myositis ossificans or heterotopic ossification. In her last follow-up 1.5 years after the surgical excision, the patient was symptom free and without signs of recurrence. To the best of our knowledge, this is the first reported case of an intra-articular ESABC located in the knee.

Epidural hematoma secondary to sinusitis: a case report and review of the literature.

Epidural hematoma is a potentially life threatening event that demands prompt diagnosis and surgical treatment, usually following head trauma. We present a case of a 9-year-old boy with no history of head trauma, and who was diagnosed with epidural hematoma secondary to frontal sinusitis; and the medical literature was reviewed.