No abstract available.
Bone Marrow/*pathology/radiography/radionuclide imaging ; Carcinoma, Adenoid Cystic/*diagnosis ; Eye Neoplasms/*diagnosis ; Female ; Humans ; Lacrimal Apparatus/*pathology/radiography/radionuclide imaging ; Lacrimal Apparatus Diseases/*diagnosis ; Maxilla ; Middle Aged ; Neoplasm Invasiveness ; Neoplasm Recurrence, Local ; *Positron-Emission Tomography ; *Tomography, X-Ray Computed

The purpose of this study was to evaluate the value of fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) for detecting the recurrence of gastric cancer. We performed a retrospective review of 139 consecutive patients who underwent PET/CT and contrast-enhanced abdominal CT (CECT) for surveillance of gastric cancer after curative resection. Recurrence of gastric cancer was validated by histopathologic examination for local recurrence or serial imaging study follow-up with at least 1 yr interval for recurrence of distant metastasis form. Twenty-eight patients (20.1%) were confirmed as recurrence. On the patient based analysis, there was no statistically significant difference in the sensitivity, specificity and accuracy of PET/CT (53.6%, 84.7%, and 78.4%, respectively) and those of CECT (64.3%, 86.5%, and 82.0%, respectively) for detecting tumor recurrence except in detection of peritoneal carcinomatosis. Among 36 recurrent lesions, 8 lesions (22.2%) were detected only on PET/CT, and 10 lesions (27.8%) only on CECT. PET/CT had detected secondary malignancy in 8 patients. PET/CT is as accurate as CECT in detection of gastric cancer recurrence after curative resection, excepting detection of peritoneal carcinomatosis. Moreover, additional PET/CT on CECT could improve detection rate of tumor recurrence and provide other critical information such as unexpected secondary malignancy.
Aged ; Female ; Fluorodeoxyglucose F18/*diagnostic use ; Humans ; Male ; Middle Aged ; Neoplasm Recurrence, Local/*diagnosis/radiography/radionuclide imaging ; Positron-Emission Tomography/*methods ; Radiopharmaceuticals/*diagnostic use ; Retrospective Studies ; Sensitivity and Specificity ; Stomach Neoplasms/*diagnosis/pathology/surgery ; Tomography, X-Ray Computed/*methods

OBJECTIVEto study the clinicopathologic features and differential diagnosis of low-grade central osteosarcoma (LGCOS).

METHODSnine cases of LGCOS were retrieved from the archival consultation files. The clinical, radiologic and pathologic features were analyzed, with literature review.

RESULTSthe mean age of the patients was 31 years. The male-to-female ratio was 3:6. All of the patients presented with painful mass and/or swelling. The sites of involvement included thigh (n = 4), tibia (n = 1), fibula (n = 1), cervical vertebra (n = 1), lumbar vertebra (n = 1) and maxilla (n = 1). Radiologic examination showed mixed lytic/blastic lesions with soft tissue shadow in 5 cases and associated periosteal reaction in 3 cases. The tumors were treated by surgical excision, with no adjuvant therapy given. The duration of follow up ranged from 2 to 43 months. Four cases had recurrence which occurred at 8 to 25 months after the operation. Gross examination showed that the tumors were fragmented on submission in 5 cases and en bloc in 4 cases. They had solid and firm cut surface, with various degree of grittiness. Histologically, LGCOS was characterized by the presence of hypocellular fibroblastic stroma associated with focal osteoid production. The spindly tumor cells showed mild degree of nuclear pleomorphism, with occasional mitotic figures demonstrated in all of the 9 cases. The newly formed neoplastic woven bone did not have any osteoblastic rimming. The bony trabeculae were slender and seam-like. Parallel arrays of woven bone were seen in 6 cases. Some of the bony trabeculae appeared irregularly branched and curved. The tumor cells permeated adjoining pre-existing bony trabeculae and bone marrow in all cases. Three cases also showed soft tissue involvement.

CONCLUSIONSLGCOS often posses important diagnostic pitfalls due to the relatively bland-looking tumor cell morphology and associated large woven or longitudinal seams of lamellar-like bone. Thorough understanding of the histologic features, when coupled with clinical and radiologic findings, are essential in arriving at a correct diagnosis.

Adolescent ; Adult ; Bone Neoplasms ; diagnostic imaging ; pathology ; surgery ; Diagnosis, Differential ; Female ; Fibrous Dysplasia of Bone ; pathology ; Fibula ; diagnostic imaging ; Histiocytoma, Benign Fibrous ; pathology ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Neoplasm Recurrence, Local ; Osteosarcoma ; diagnostic imaging ; pathology ; surgery ; Radiography ; Radionuclide Imaging ; Reoperation ; Thigh ; diagnostic imaging ; pathology ; Young Adult