Periosteal chondroma of the ischium; an unusual location.

Periosteal chondroma is a rare benign tumor of hyaline cartilage. Periosteal chondroma arising in the ischium is an extremely rare event. By presenting this case report, we aim to remind that differential diagnosis of these lesions should be carefully performed especially for unusual locations. A 51-year-old man visited the orthopedics clinic with the complaints of left pelvic mass and pain lasting about one year. Computed tomography showed a solid mass with abundant specks of calcification that was 4x5 cm in diameter and associated with the ischium of the left pelvic bone. There was no evidence of penetration into the medullary cavity and cortical sclerosis. No radiological aggressive appearance was observed. The lesion was removed with the covering periosteum. Microscopically, there were lobules of hyaline cartilage composed of chondrocytes with foci of endochondral ossification and calcification. The case was reported as 'periosteal chondroma'. In conclusion, this case report presents a case of periosteal chondroma, a rare tumor, which occurred in an unusual location and age range. The differential diagnosis of periosteal chondroma from malignant lesions is necessary for avoiding aggressive and inappropriate treatment.

Granular cell tumor of the posterior tibial nerve as a rare cause of heel pain: a case report.

Granular cell tumor of peripheral nerves is extremely rare. We present the case of a patient with a well-capsulated intraneural granular cell tumor involving the posterior tibial nerve, who presented with chronic heel pain mimicking plantar fasciitis. Magnetic resonance imaging revealed a well-defined intraneural soft-tissue mass within the substance of the posterior tibial nerve. Histopathologic examination showed a granular cell tumor, which is extremely rare in the peripheral nerves. Heel pain is one of the common conditions handled by physicians, podiatrists, and orthopedic surgeons. Posterior tibial nerve lesions at the leg should be kept in mind in the differential diagnosis of patients with persistent heel and foot pain. Magnetic resonance imaging is a useful method in the anatomical evaluation of focal intraneural lesions.

Prognostic significance of anaplasia and angiogenesis in childhood medulloblastoma: a pediatric oncology group study.

The purpose of this study was to investigate whether quantitative assessment of cytologic anaplasia and angiogenesis may predict the clinical prognosis in medulloblastoma and stratify the patients to avoid both undertreatment and overtreatment. Medulloblastomas from 23 patients belonging to the Pediatric Oncology Group were evaluated with respect to some prognostic variables, including histologic assessment of nodularity and desmoplasia, grading of anaplasia, measurement of nuclear size, mitotic cell count, quantification of angiogenesis, including vascular surface density (VSD) and microvessel number (NVES), and immunohistochemical scoring of vascular endothelial growth factor (VEGF) expression. Univariate and multivariate analyses for prognostic indicators for survival were performed. Univariate analysis revealed that extensive nodularity was a significant favorable prognostic factor, whereas the presence of anaplasia, increased nuclear size, mitotic rate, VSD, and NVES were significant unfavorable prognostic factors. Using multivariate analysis, increased nuclear size was found to be an independent unfavorable prognostic factor for survival. Neither the presence of desmoplasia nor VEGF expression was significantly related to patient survival. Although care must be taken not to overstate the importance of the results of this single-institution preliminary report, pathologic grading of medulloblastomas with respect to grading of anaplasia and quantification of nodularity, nuclear size, and microvessel profiles may be clinically useful for the treatment of medulloblastomas. Further validation of the independent prognostic significance of nuclear size in stratifying patients is required.