RESUMEN
Gastrointestinal stromal tumors (GISTs) albeit rare, are the most common mesenchymal neoplasms of our gastrointestinal (GI) tract. GISTs present with nonspecific symptoms and are found incidentally on endoscopy or imaging. A significant portion of GIST diagnoses expresses KIT/CD117 and DOG-1 tissue markers which are pathognomonic for GIST. More recently, Ki-67 was found to be a significant prognostic marker for determining the risk of recurrence. We present a patient with a mesenchymal mass in the small intestine with pathognomonic features of GIST and expression of Ki-67, an important immunocytochemical marker of proliferation. The patient was a 71-year-old male with a history of hyperlipidemia and hypertension. He presented to the emergency department complaining of bloody diarrhea for two days, with associated nausea, vomiting, and abdominal cramping. Initial blood pressure on presentation was 77/52 mm Hg. Computed tomography (CT) of the abdomen and pelvis revealed a large solid mass with cystic components. The mass was not visualized with esophagogastroduodenoscopy or colonoscopy, and surgical intervention was warranted. A 14 cm x 11.5 cm x 10 cm tumor was found in the ileum. The tumor was excised with small bowel segmental resection and the specimen was sent for pathological evaluation. Immunohistochemical analysis confirmed the diagnosis of GIST with diffuse CD117/c-Kit protein expression. The tumor was high grade with a high mitotic rate at 30 mitoses/50 high-power fields (HPF) and had spindle cell morphology. Of note, 10% of the tumor cells were positive for Ki-67. GISTs have a high risk of recurrence and a more favorable prognosis with advancements in management. Prior to imatinib therapy in the early 2000s, GISTs prognosis was very poor, as they are resistant to most conventional chemotherapeutic agents and radiation. While the prognosis is fair, surgical resection and imatinib therapy have improved outcomes and risk of recurrence. Prognosis and risk of recurrence can be determined by assessing the mitotic rate, tumor size, and recently, expression of Ki-67. Ki-67 provides a reliable and reproducible approach to assess the prognosis of GIST.
RESUMEN
BACKGROUND: We describe a thick fascial band arising from the medial aspect of the lateral plantar aponeurosis diving deep into the forefoot crossing over a branch of the lateral plantar nerve. Because a review of current literature resulted in limited and outdated sources, we sought to first determine the frequency of this fascial band and the location where it crosses the lateral plantar nerve and, second, discuss the clinical applications these anatomical findings could have. METHODS: 50 pairs of cadaveric feet (n = 100) were dissected to investigate for presence of the fascial band and its interaction with the lateral plantar nerve. Images were taken of each foot with the fascial band. ImageJ was used to take 2 measurements assessing the relationship of the tuberosity of the base of the fifth metatarsal to where the nerve crossed deep to the fascial band. RESULTS: Overall, 38% of the feet possessed the fascial band. It was found unilaterally in 10 pairs and bilaterally in 14 pairs. On average, the point at which the lateral plantar nerve passed deep to the fascial band was 2.0 cm medial and 1.7 cm anterior to the tuberosity of the base of the fifth metatarsal. CONCLUSION: When present, the deep band of the lateral plantar aponeurosis (PA) was consistently found to be crossing the lateral plantar nerve. The discovery of the location where this most commonly occurs has not been previously reported and adds an interesting dimension that elevates an anatomical study to one that has clinical potential. CLINICAL RELEVANCE: The established target zone gives a precise location for where the relationship between the deep band of the lateral PA and the lateral plantar nerve exists when evaluating the foot. The target zone provides a potential springboard for future investigations concerning said relationship clinically.