The lipoma-like hibernoma: A case report of a rare entity.

Hibernoma is a rare tumor developing from fat cells. It is a slowly evolving, benign tumor that is rarely pain-inducing. The most frequently encountered histological form is the typical hibernoma. The main differential diagnosis is liposarcoma. Here we present a case of a lipoma-like tumor of the arm: a rare variant of hibernoma. A 45-year-old man presents with a swelling of the left arm evolving for one year. Physical examination revealed a mobile, firm, and well-defined mass of the lateral left upper arm measuring 5 cm in length with no cutaneous lesions overlying. MRI and ultrasound confirmed the presence of a highly vascularized mass suggestive of a liposarcoma. A biopsy of the mass was performed concluding to a lipoma with no evident signs of malignancy. The patient underwent a surgical resection of the mass. Histopathological examination showed a well-differentiated adipose proliferation arranged in diffuse patterns of mature adipocytes. Large hibernoma-like foci were also noted. The diagnosis of a lipoma-like hibernoma was confirmed. Hibernoma represents is an uncommon benign tumor. It usually occurs in areas where the brown fat persists, including the thighs, shoulders, back, and neck in decreasing frequency. Commonly, this tumor occurs between the second and third decades of life. Clinically, it presents as a slow growing, painless mass. It may occasionally be painful due to compression of the surrounding structures. MRI shows T1w and T2w hyperintensity, with contrast enhancement after gadolinium injection. On histopathological examination, the structure is distinguished by an association of mature cells, round cells with central nuclei and eosinophilic cytoplasm, and multivacuolated cells. Surgical excision is the optimal treatment. The differential diagnosis concerns lipomas and well-differentiated liposarcomas. Lipoma-like hibernoma is an uncommon benign tumor which might imitate a liposarcoma clinically and radiologically. Histopathological examination is necessary to establish the diagnosis.

Chordoma of the lumbar spine-A potential diagnosis not to be forgotten!

Chordoma is a rare, malignant neoplasm thought to develop from the notochord. It most commonly occurs in the base of the cranium or the sacro-coccygeal region but around 15%-20% affect the vertebral body. Extra-lesional resection with or without adjuvant radiotherapy is generally accepted as the mainstay of treatment for this slow-growing tumor. We present a case whereby a patient with an extensive vertebral body lesion causing caudal compression, treated with spinal decompression and posterior stabilization. This case highlights the importance of pre-operative tissue diagnosis, and that, although rare (0.8 per 100,000), chordoma should always be considered.

Alkaptunuria; a case report.

INTRODUCTION AND IMPORTANCE: Alkaptonuria is an autosomal recessive disease due to lack of the enzyme homogentisic acid oxidase. Homogentisic Acid (HA) is in the metabolism pathway of phenylalanine. The musculoskeletal symptomatology begins generally in the fourth decade. We reported the case of a 50 year old man who had ochronotic arthropathy and degenerative changes in knee joint and who was treated with total knee arthroplasty. CASE PRESENTATION: A 50 year old man presented to our outpatient clinic with bilateral knee pain. Pain was exaggerated with effort and decreases with rest. The patient had no medical history. While performing the total knee arhtroplasty for our patient, we discovered intraoperatively the black coloration of the articular cartilage of the knee. At 6 months follow up, the patient was satisfied with the result with no knee pain in the treated knee. Range of knee motion was 0° in total extension to 100° of flexion. Radiological control showed a stable prosthesis not affected by ochronose. CLINICAL DISCUSSION: Alkaptonuria is caused by lack of the enzyme homogentisic acid oxidase, is a rare autosomal recessive disease leading accumulation of homogentisic acid in connective tissue. This leads to many manifestations such as urinary, cardiac, dermatologic, ophthalmologic or musculoskeletal symptoms. Deposit of Homogentisic acid in articular cartilage gives the characteristic black or dark brown pigmentation of the cartilage. Its clinical traduction is symptomatology of degenerative modifications in multiples joints such as knee, shoulder or hip beside the lumbar spine arthrosis. CONCLUSION: Alkapyonuria is a very rare condition. Revealed by its orthopedic features is exceptionally. The patients, generally, need articulations replacement and the illness have no effect on its prognosis.

Dermatofibrosarcoma protuberans of the hallux: A case report with review of the literature.

INTRODUCTION AND IMPORTANCE: Darier-Ferrand dermatofibrosarcoma (DFS) is a rare mesenchymal tumor with an aggressive local behavior, high local recurrence frequency and low metastatic potential. It commonly presents as a raised slowly growing mass. It usually occurs on trunk and proximal extremities but rarely touches distal extremities such as hands, fingers, or foot below knees. CASE PRESENTATION: A 15-year-old girl presents with a protuberant painful mass of the right hallux of 2 years. After surgical excision, histological examination revealed a spindle shaped cells with a strong CD34 expression and the diagnosis of Darier-Ferrand dermatofibrosarcoma of the toe was confirmed. We proceeded to a review of the literature of Dermatofibrosarcoma on the toes with the aim to reveal, its clinical presentations, histopathology, and treatment options. CLINICAL DISCUSSION: DFS represents 0.1 % of all cancers. It is a low-grade sarcoma with a locally aggressive behavior and a low metastatic potential. Only 11 cases of DFS of the toes have been reported in the literature. It usually occurs in the trunk, and proximal extremities. Histological and immunohistochemical examination are mandatory to confirm the diagnosis with diffuse expression of CD34 by the tumoral cells. Surgery is the standard treatment for localized and resectable lesions. CONCLUSION: Darier-Ferrand Dermatofibrosarcoma is an uncommon and recurrent dreadful tumor, that rarely occurs on toes, but should be considered in front of persistent slowly growing foot lesions.

Case Report: Synchronous bilateral lipoma arborescens of the bicipitoradial bursa.

Background: Lipoma arborescens (LA) is an infrequent benign tumor made of mature sub-synovial fatty cell proliferation that may arise into the synovial joint, the bursae or the tendon sheaths. This condition affects mainly the knee joint, but the bicipitoradial bursa is an exceptional location. We report herein a case of a synchronous bilateral (LA) of the bicipitoradial bursa. Case presentation: A 52-year-old patient, with no medical history, presented with a swelling of both front arms that had been progressing for nine years. Physical examination showed a mass in the antecubital fossae of 3cm on the left side and 0.5cm on the right side. Both masses were tender, well-defined, fixed, without inflammatory signs and painful on elbow flexion. A magnetic resonance imaging (MRI) scan was performed, revealing the presence of a septate soft-tissue mass of the distal portion of the brachial muscle of 70x46x27mm. This mass had a heterogeneous fat signal in its depth and a homogeneous fat composition on the outside. The diagnosis of liposarcoma was suspected. The patient underwent surgery to remove both masses. Gross examination showed a characteristic frond-like or digitiform pattern. Microscopical examination demonstrated papillary proliferation of the synovial villi. The final diagnosis was of LA. The patient had no complications and there was no recurrence of LA. Conclusions: LA is a rare condition, and the bicipitoradial bursa is an exceptional location. Histological confirmation is mandatory to correct the diagnosis.