UNASSIGNED: Aneurysmal bone cyst is a benign, most often non-neoplastic lesion affecting the bone. Malignant transformation is reported in certain cases, although rare. It commonly occurs in young adults with around 75% of the cases occurring in the first two decades and 95% occurring in the first 3 decades. The management depends on the individual case parameters with ABC occurring in a weight-bearing area of a bone warranting an aggressive treatment plan with the consideration of preventing a pathological fracture.
UNASSIGNED: A 20-year-old male patient with no other comorbidities presented to us with complaints of atraumatic right hip pain of 9-month duration. On preliminary clinical examination and imaging studies with X-rays, CT scan, and MRI, the patient was diagnosed to have an aneurysmal bone cyst (ABC) of the right proximal femur. The patient was operated with intra-lesional excision with extended curettage and prophylactic fixation with DHS plating and kept on yearly follow-up. 10-year follow-up showed complete resolution of the lesion and implant removal was done after that.
UNASSIGNED: As is clear from this case, the treatment of an aneurysmal bone cyst needs to individualized based on the patient\'s age, complaints, and tumor behavior in terms of its aggressiveness, size, and its extent. Often, en bloc excision with extensive curettage is required along with bone grafting and prophylactic fixation to support the bone graft and to prevent a pathological fracture and further recurrence. Implant removal if indicated should be done after complete resolution of the lesion, patient willingness, and any other medical indication.

UNASSIGNED: Vertebral body osteochondroma presenting with myelopathic symptoms is exceptionally rare entity of spinal osteochondroma which arises from the posterior surface of vertebral body and leading to spinal canal stenosis and cord compression. Early definitive diagnosis and subsequent successful treatment is necessary in such cases to prevent life threatening complications.
UNASSIGNED: In this context, we report a case of a 20-years old female presented with mechanical neck pain, unsteady gait, giddiness with neurological deficit for the past 3 months. An MRI of the cervical spine revealed a mass growing from the posterior aspect of the C6 vertebral body and extending toward the vertebral canal, causing marked spinal cord compression.
UNASSIGNED: The following case report not only describes the rare presentations of vertebral body osteochondroma but also emphasizes on surgical management by en bloc resection of tumor and anterior cervical fusion, resulting in a favorable outcome without any recurrence.

UNASSIGNED: A malignant peripheral nerve sheath tumor (MPNST) is a rare soft-tissue sarcoma with a high recurrence rate and poor prognosis. Early diagnosis and complete surgical excision are the fundamental principles of treatment. A benign presentation and low clinical suspicion often delay definitive diagnosis, and en bloc excision may not be feasible depending on the size and location of the tumor. We describe a rare case of a recurrent MPNST successfully treated by surgical excision.
UNASSIGNED: A 35-year-old woman presented with a rapidly growing painful mass 3 months following incomplete removal of a MPNST from her forearm. Staging investigations showed no evidence of metastasis. The patient underwent en-bloc surgical excision, split skin grafting, and adjuvant radiation therapy. Histology and immunohistochemical analysis confirmed a MPNST. Five years after having surgery, the patient shows no evidence of recurrence and has excellent function.
UNASSIGNED: MPNST are rare soft tissue sarcomas that can masquerade as benign lumps. There is a paucity of literature on the outcome of surgically-treated recurrent disease. Notwithstanding local recurrence of the tumor, complete surgical excision can yield excellent clinical results.

Osteochondroma is one of the most common benign bone tumors, mainly involving the bone ends of long bones, and involving the spine is rare. It often involves the competing, followed by the thoracic and lumbar spine, and rarely involves the sacrum. We report the imaging findings of a solitary osteochondroma of the sacrum. The patient was a 37-year-old woman who presented clinically with progressive low back pain associated with left buttock pain and discomfort. CT and MRI showed that the lesion originated from the left lamina of S1 and grew anteriorly and superiorly, resulting in compressive resorption of the L5 vertebral bone, left foraminal stenosis and adjacent nerve root swelling. The patient underwent surgery and the mass was completely excised and recovered well postoperatively. Osteochondroma arising from the sacrum is rare and can lead to compressive resorption of adjacent bone, and imaging techniques are conducive to the localization and characterization of the lesion and provide useful information for clinical treatment.

UNASSIGNED: Osteochondroma is the most common benign bone tumor where a chondrogenic lesion is derived from aberrant cartilage from the perichondral ring. Although it commonly arises from the growing ends of long bones, less commonly, it may arise from the scapula, pelvis, or vertebra.
UNASSIGNED: We encountered a 16-year-old male patient with a painless left pelvic solid mass for 3 years, which was suggestive of osteochondroma on X-ray and magnetic resonance imaging findings. Besides cosmetic issues, the main indication for surgery was the constant discomfort in wearing pants/shorts/belts. He underwent en bloc excision followed by a biopsy of the surgical specimen by two independent histopathologists confirming the tumor to be osteochondroma. He was followed up for 2 years with no signs of post-operative complications or recurrence. This case represents one of the very few reported so affecting the iliac wing, where the excision was performed before skeletal maturation. We also performed a review of the current literature on iliac wing osteochondroma to understand the tumor better, identify gaps in current knowledge, and suggest areas for future research.
UNASSIGNED: Since one of the differential diagnoses includes secondary chondrosarcoma, which could be a rare progression of osteochondroma, early recognition and comprehensive evaluation of such unusual cases needs to be dealt with a high index of suspicion to avoid misdiagnosis and to provide effective treatment.

BACKGROUND: Dedifferentiated liposarcoma (DDLS) has a worse prognosis and occurs most commonly in the retroperitoneal region and rarely in the intraperitoneal region. Histological diagnosis was revolutionized by the combined contributions of histo-immuno-chemistry and molecular biology. Aside from surgery, there is no consensus on the optimal treatment for this chemoresistant cancer.
METHODS: A thirty-year-old black female presented with a large painful abdominal mass occupying nearly the entire abdomen and progressive weight loss was admitted for surgery. Abdominal computed tomography showed a large heterogeneous mass of the mesentery that was sized 18 cm × 16 cm in size and had heterogeneous contrast enhancement. During laparotomy, en bloc excision of the large and multilobulated gastrocolic ligament mass was performed. The initial postoperative histopathological diagnosis was undifferentiated sarcoma. Finally, the results of immunohistochemistry and molecular biology allowed us to confirm the diagnosis of DDLS. The tumour followed an aggressive evolution with diffuse metastasis, causing the death of the patient less than 5 mo after the operation.
CONCLUSIONS: Dedifferentiated liposarcomas are rare tumours that typically originate in the retroperitoneum but may arise in unexpected locations.

Hemangioblastomas are benign World Health Organization grade 1 tumors that are relatively rare.1 They may be sporadic or found in association with von Hippel-Lindau disease. Posterior fossa hemangioblastomas arise in the cerebellar hemisphere and, less commonly, at other sites such as medullary hemangioblastomas.2-4 Their characteristic radiologic features including solid-cystic morphology and prominent vessels aid in the preoperative diagnosis.5 In this operative video, we discuss the technical nuances and steps to avoid complications while operating on a large medullary hemangioblastoma. A 19-year-old lady presented with headache, vomiting, and visual deterioration of 2 months\' duration. On examination, she had visual acuity of 4/60 right side, 6/60 left side, bilateral papilledema, and truncal and gait ataxia. Since she had presented in altered sensorium and a computed tomography head scan showed hydrocephalus, a ventriculoperitoneal shunt was placed on an emergency basis. Proper radiologic workup was done. On the basis of radiologic findings, she was provisionally diagnosed to have hemangioblastoma and surgery was planned. Preoperative angiogram showed an intense tumoral blush, but embolization was deemed infeasible since the tumor had multiple feeding vessels. Definitive surgery for tumor excision was performed 5 days after the shunt surgery. The patient\'s family consented to the procedure and the use of images and clinical data for publication. Video 1 highlights the tumor location, its prominent blood supply and venous drainage, use of intraoperative neuromonitoring, and the technical nuances for an en bloc excision. The patient had a left lateral gaze (sixth nerve) palsy in the immediate postoperative period, which resolved over the next 3 months. Postoperative and follow-up imaging confirmed complete tumor excision. Modern microsurgical techniques and a thorough understanding of the tumor vasculature help in performing safe and complete excision of such tumors.1,2 En bloc excision remains the mainstay of surgery for hemangioblastomas.

UNASSIGNED: Arteriovenous malformations (AVM) are developmental vascular malformations consisting of abnormal arteriovenous shunts surrounding a central nidus. These lesions are relatively uncommon, comprising just 7% of all benign soft-tissue masses. Most AVMs occur in the brain, neck, pelvis, and lower extremity and rarely manifest in the foot. When they do form in the foot, non-specific pain and the absence of clinical features contribute to the high rate of misdiagnosis on initial presentation. Although surgical excision combined with embolotherapy has emerged as the preferred treatment for large AVM, controversy exists over the best treatment for small lesions in the foot.
UNASSIGNED: A 36-year-old Afro-Caribbean man was referred to the clinic with a 2-year history of increasing pain in his forefoot, affecting his ability to stand or walk comfortably. There was no history of trauma, and despite changing his footwear, the patient continued to have significant pain. Clinical examination was unremarkable except for mild tenderness over the dorsum of his forefoot, and radiographs were normal. A magnetic resonance scan reported an intermetatarsal vascular mass but could not exclude malignancy. Surgical exploration and en bloc excision confirmed the mass to be an AVM. One year post-surgery, the patient remains pain-free with no evidence of recurrence.
UNASSIGNED: The rarity of AVM in the foot, combined with normal radiographs and non-specific clinical signs, contributes to the long delay in diagnosing and treating these lesions. Surgeons should have a low threshold for obtaining magnetic resonance imaging in cases of diagnostic uncertainty. En bloc surgical excision is an option for treating small suitably located lesions in the foot.

A giant cervical goiter, defined as a thyroid mass larger than 8 cm in diameter, is usually a nodular or adenomatous goiter. A giant cervical goiter can also be caused by hyperthyroidism (i.e., Hashimoto\'s thyroiditis). The surgical indications for patients with Hashimoto\'s disease include suspected malignant tumors, persistent symptoms related to the disease, or persistent enlargement of the goiter. We herein describe a woman who developed symptoms of compression from a thyroid tumor, the volume of which was almost the largest reported in the relevant literature to date. The bilateral lobes of the giant thyroid tumor were removed by total en bloc excision. We protected the bilateral recurrent laryngeal nerve and preserved the bilateral upper and lower parathyroid glands in situ. The excised left lobe tumor was 16 × 9 × 5.5 cm, whereas the right lobe tumor was 12 × 8 × 4 cm. The pathological diagnosis was Hashimoto\'s thyroiditis. Although surgical excision is difficult, it is still the main treatment modality for giant goiters in patients with Hashimoto\'s thyroiditis and can help to reduce the occurrence of complications.

UNASSIGNED: Upper tract urothelial carcinoma (UTUC) is a highly systemic aggressive disease with a tendency of rapid lymph node invasion and metastasis presenting poor oncologic outcomes. Ureteral localization of tumors leads to hydronephrosis and early invasion of the muscle wall, being categorized as high risk tumors.
METHODS: A 70 years old female was diagnosed with lower left ureteral urothelial tumor associated with hydronephrosis and paraaortic and iliac enlarged lymph nodes. The disease was stratified as high risk upper tract urothelial carcinoma. Treatment consisted in en bloc radical nephroureterectomy, bladder cuff excision and wide lymph node dissection using a combined robotic and 3D laparoscopic approach.
UNASSIGNED: Surgical challenges are surpassed by the use of minimal invasive approaches that offer precise dissection and tissue manipulation with a fast postoperative recovery and early adjuvant oncologic treatment. Comprehensive and complete lymph node dissection along with precise bladder cuff excision offers improved staging, possibly impacting disease prognosis.
CONCLUSIONS: En bloc minimal invasive radical nephroureterectomy, bladder cuff excision and wide lymph node dissection offer improved surgery time and lymph node dissection, better management of distal ureteral and bladder cuff excision, watertight cystorrhaphy and optimal disease staging. The experience of the main surgeon with 3D laparoscopy was used in the hereby case to optimize operatory time for the renal step of the surgery. The gentle and precise movements of the Da Vinci robot allowed an accurate en bloc dissection (pN2, N4+/15) with implications in staging and possibly also in oncologic outcomes.