Gastrointestinal stromal tumors (GISTs) are rare neoplasms of the gastrointestinal tract associated with high rates of malignant transformation. Most GISTs present asymptomatically. They are best identified by computed tomography (CT) scan and most stain positive for CD117 (C-Kit), CD34, and/or DOG-1. There have been many risk stratification classifications systems which are calculated based on tumor size, mitotic rate, location, and perforation. The approaches to treating GISTs are to resect primary low-risk tumors, resect high-risk primary or metastatic tumors with imatinib 400 mg daily for 12 months, or if the tumor is unresectable, neoadjuvant imatinib 400 mg daily followed by surgical resection is recommended. Sunitinib is required for KIT exon 9, 13, and 14 mutations, while ponatinib is used for exon 17 mutations and regorafenib for highly refractory tumors. High-risk tumors should be monitored for recurrence with serial abdominal CT scans. Radiofrequency ablation has shown to be effective when surgery is not suitable. Newer therapies of ipilimumab, nivolumab, and endoscopic ultrasound alcohol ablation have shown promising results. This report addresses the epidemiology, clinical presentation, diagnostic imaging, histologic diagnosis, classification and risk stratification, staging and grading, surgical treatment, adjuvant treatment, and metastasis of GISTs.

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Both implants are capable of maintaining hyaline-appearing tissue at 24 weeks. The physicochemical region between the cartilage and bone compartments makes these devices well suited for delivery of different growth factors or drugs in each compartment, or different doses of the same factor. It also renders these devices excellent vehicles for chondrocyte or stem cell transplantation.

Degenerative lumbar spinal stenosis is caused by mechanical factors and/or biochemical alterations within the intervertebral disk that lead to disk space collapse, facet joint hypertrophy, soft-tissue infolding, and osteophyte formation, which narrows the space available for the thecal sac and exiting nerve roots. The clinical consequence of this compression is neurogenic claudication and varying degrees of leg and back pain. Degenerative lumbar spinal stenosis is a major cause of pain and impaired quality of life in the elderly. The natural history of this condition varies; however, it has not been shown to worsen progressively. Nonsurgical management consists of nonsteroidal anti-inflammatory drugs, physical therapy, and epidural steroid injections. If nonsurgical management is unsuccessful and neurologic decline persists or progresses, surgical treatment, most commonly laminectomy, is indicated. Recent prospective randomized studies have demonstrated that surgery is superior to nonsurgical management in terms of controlling pain and improving function in patients with lumbar spinal stenosis.

Metastatic acetabular disease can be severely painful and may result in loss of mobility. Initial management may consist of diphosphonates, narcotic analgesics, radiation therapy, protected weight bearing, cementoplasty, and radiofrequency ablation. Patients with disease affecting large weight-bearing regions of the acetabulum and with impending failure of the hip joint are unlikely to gain much relief from nonsurgical treatment and interventional procedures. The profound osteopenia of the acetabulum, limited healing potential of the fracture, and projected patient life span and function necessitate surgical techniques that provide immediate stable fixation to reduce pain and restore ambulatory function. Current reconstructive procedures, including cemented total hip arthroplasty, the saddle or periacetabular endoprosthesis, and porous tantalum implants, are based on the quality of remaining acetabular bone as well as the patient's level of function and general health. Well-executed acetabular reconstructions can provide durable hip joints with good pain relief and function.