A model for in vivo serial investigation of hepatic metabolism using 31P nuclear magnetic resonance spectroscopy.

We have developed an animal model which allows serial, in vivo, evaluation of high energy phosphate metabolism in rat liver, using 31P nuclear magnetic resonance spectroscopy (MRS). In seven rats, the left lobe of the was surgically relocated into a subcutaneous position. The animals recovered quickly from the surgery and continued to thrive. Localization of the liver was obtained using simple surface coil technology. Typical MRS data acquisition times were less than 45 minutes. After the 28 days, the livers showed both normal histology and 31P metabolic measures.

The prognostic significance of tumor ploidy and pathology in adenocarcinoma of the esophagogastric junction.

Tumor DNA content has been advocated to be an important prognostic indicator in human malignancies. Paraffin-embedded specimens of 75 resected adenocarcinomas (AC) of the esophagogastric junction were studied by flow cytometric DNA analysis to determine whether tumor ploidy was a significant prognostic variable independent of stage and histologic grade of the tumor. Eighty-one percent of the tumors were aneuploid. More patients with aneuploid tumors had lymph node metastases than patients with diploid tumors (P = 0.007). Patients with aneuploid tumors had poorer 18-month disease-free and overall survival than patients with diploid tumors. Cox regression analysis demonstrated that the most important prognostic variables for predicting overall survival were lymph node status, depth of wall invasion, and tumor differentiation. Tumor ploidy was not an independent prognostic variable in predicting recurrent disease or death from AC of the esophagogastric junction. Tumor DNA content is valuable, however, as a marker for patients at increased risk of lymph node metastases, early recurrence, and poorer survival.

Effect of cancer on the in vivo energy state of rat liver and skeletal muscle.

The effect of increasing tumor burden on host liver and skeletal muscle energy status was studied using P-31 nuclear magnetic resonance spectroscopy (NMR), in rats inoculated with a nonmetastasizing methylcholanthrene-induced sarcoma (TB), and compared to nontumor bearing (NTB) and pair-fed (PF) rats. During the 28-day study, serial measurements of body weight, food intake, and tumor volume were obtained. Using a 0.9-cm double-turn surface coil, weekly NMR measurements were obtained from liver and skeletal muscle. An increasing ratio of [Pi]/[ATP] was used as one measure of intracellular energy depletion. [Pi]/[ATP] in NTB rats remained constant over time at 0.78 +/- 0.10 in liver, and 0.30 +/- 0.10 in skeletal muscle. In TB rats, the [Pi]/[ATP] ratio increased significantly in liver (P = 0.00002) and skeletal muscle (P = 0.04) with increasing tumor burden. In PF rats, no significant change occurred in [Pi]/[ATP] in liver or skeletal muscle, indicating that declining food intake was not responsible for the change in [Pi]/[ATP] seen in TB rats. Surface-coil spectroscopy of liver and skeletal muscle permits serial measurement of visceral energy stores. Increasing tumor burden results in early, ongoing depletion of energy stores as reflected by increasing [Pi]/[ATP] in these organs.

Staging laparotomy for Hodgkin's disease in children.

Staging laparotomy in patients with Hodgkin's disease continues to be a controversial procedure in their management. Between 1970 and 1986, 67 patients up to 18 years of age were seen with Hodgkin's disease. The results of staging laparotomy performed on 39 of these children are reviewed. The clinical stage was changed as a result of laparotomy in 43.6% of cases, with 12.8% of cases upstaged and 30.8% of cases downstaged. All changes in stage modified the proposed treatment for the patient. In 20.5% of patients the laparotomy was positive, and in all cases the spleen was involved. Preoperative lymphangiography did not accurately identify nodal disease. Of the patients with negative laparotomies, 10% developed relapse in the abdomen. Major complications included three episodes of bacterial sepsis, with one death due to Streptococcal pneumonia and one to Neisseria gonorrhea. All septic events occurred prior to the use of pneumococcal vaccine and prophylactic antibiotics. One patient required reoperation for intestinal obstruction with bowel resection. None of the currently used noninvasive tests accurately identifies intraabdominal disease. Therefore, staging laparotomy continues to play an important role in the early management of Hodgkin's disease.

Esophageal function following Livaditis repair of long gap esophageal atresia.

Proximal pouch esophagomyotomy (Livaditis) allows for repair of long gap esophageal atresia (EA). Postoperative esophageal functional studies in these patients are lacking. Six such infants were followed for up to 42 months. Esophageal function was assessed clinically and by barium swallow, manometry, 24 hr pH monitoring, esophagoscopy, and biopsy. Operative complications included two minor anastomotic leaks and two asymptomatic diverticula at the myotomy site. All patients had dysmotility on barium swallow. Gastroesophageal reflux (GER) was seen in four. Manometry showed a variable aperistaltic segment in each infant but lower esophageal sphincter pressures and relaxation were retained. Twenty-four hour pH monitoring showed an increase in frequency and duration of GER. All four patients biopsied had esophagitis. Five of the six patients showed normal growth velocity. Livaditis modified repair of EA was not associated with significant surgical complications. Esophageal motility showed abnormalities similar to those reported after the standard repair of EA. Myotomy did not adversely affect the esophageal function.