(18)F-fluorodeoxyglucose positron-emission tomography-computed tomography to diagnose recurrent cancer.

BACKGROUND: Sometimes the diagnosis of recurrent cancer in patients with a previous malignancy can be challenging. This prospective cohort study assessed the clinical utility of (18)F-fluorodeoxyglucose positron-emission tomography-computed tomography ((18)F-FDG PET-CT) in the diagnosis of clinically suspected recurrence of cancer. METHODS: Patients were eligible if cancer recurrence (non-small-cell lung (NSCL), breast, head and neck, ovarian, oesophageal, Hodgkin's or non-Hodgkin's lymphoma) was suspected clinically, and if conventional imaging was non-diagnostic. Clinicians were asked to indicate their management plan before and after (18)F-FDG PET-CT scanning. The primary outcome was change in planned management after (18)F-FDG PET-CT. RESULTS: Between April 2009 and June 2011, 101 patients (age, median 65 years; 55% female) were enroled from four cancer centres in Ontario, Canada. Distribution by primary tumour type was: NSCL (55%), breast (19%), ovarian (10%), oesophageal (6%), lymphoma (6%), and head and neck (4%). Of the 99 subjects who underwent (18)F-FDG PET-CT, planned management changed after (18)F-FDG PET-CT in 52 subjects (53%, 95% confidence interval (CI), 42-63%); a major change in plan from no treatment to treatment was observed in 38 subjects (38%, 95% CI, 29-49%), and was typically associated with (18)F-FDG PET-CT findings that were positive for recurrent cancer (37 subjects). After 3 months, the stated post-(18)F-FDG PET-CT management plan was actually completed in 88 subjects (89%, 95% CI, 81-94%). CONCLUSION: In patients with suspected cancer recurrence and conventional imaging that is non-diagnostic, (18)F-FDG PET-CT often provides new information that leads to important changes in patient management.

Postoperative extended-volume external-beam radiation therapy in high-risk esophageal cancer patients: a prospective experience.

BACKGROUND AND PURPOSE: Extended-volume external-beam radiation therapy (RT) following esophagectomy is controversial. The present prospective study evaluates the feasibility of extended-volume RT treatment in high-risk esophagectomy patients with a cervical anastomosis receiving postoperative combined chemoradiation therapy. PATIENTS AND METHODS: From 2001 to 2006, 15 patients with resected esophageal cancer were prospectively accrued to this pilot study to evaluate the adverse effects of extended-volume RT. Postoperative management was carried out at London Regional Cancer Program. Eligibility criteria were pathology-proven esophageal malignancy (T3-4, N0-1), disease amenable to surgical resection, and esophagectomy with or without resection margin involvement. Patients with distant metastases (M1) and patients treated with previous RT were excluded. All 15 study patients received 4 cycles of 5-fluorouracil-based chemotherapy. External-beam RT was conducted using conformal computed tomography planning, with multi-field arrangement tailored to the pathology findings, with coverage of a clinical target volume encompassing the primary tumour bed and the anastomotic site in the neck. The radiation therapy dose was 50.40 Gy at 1.8 Gy per fraction. The RT was delivered concurrently with the third cycle of chemotherapy. The study outcomes-disease-free survival (DFS) and overall survival (OS)-were calculated by the Kaplan-Meier method. Treatment-related toxicities were assessed using the U.S. National Cancer Institute's Common Toxicity Criteria. RESULTS: The study accrued 10 men and 5 women of median age 64 years (range: 48-80 years) and TNM stages T3N0 (n = 1), T2N1 (n = 2), T3N1 (n = 11), and T4N1 (n = 1). Histopathology included 5 adenocarcinomas and 10 squamous-cell carcinomas. Resection margins were clear in 10 patients. The median follow-up time was 19 months (range: 3.5-53.4 months). Before radiation therapy commenced, delay in chemotherapy occurred in 20% of patients, and dose reduction was required in 13.3%. During the concurrent chemoradiation therapy phase, 20% of the patients experienced chemotherapy delay, and 6.6% experienced dose reduction. No patient experienced treatment-related acute and chronic esophagitis above grade 2. Disease recurred in 40% of the patients (6/15), and median time to relapse was 24 months. No tumour recurred at the anastomotic site. The median DFS was 23 months, and the median OS was 21 months. CONCLUSIONS: Extended-volume external-beam RT encompassing the tumour bed and the anastomotic site is feasible and safe for high-risk T3-4, N0-1 esophageal cancer patients after esophagectomy.

Gluconeogenesis in the tumor-influenced rat hepatocyte: importance of tumor burden, lactate, insulin, and glucagon.

In an attempt to define the relationship between tumor burden (cachexia) and host hepatocyte gluconeogenesis, the following experiments were performed with the use of an F344 male rat bearing a transplantable sarcoma. Food intake of tumor-bearing (TB) rats was constant until day 24 following implant and a tumor burden of 18 +/- 5.2% (mean +/- SD), at which time food intake progressively declined daily. Tumor burden was arbitrarily divided at 12.8% to determine if any measured changes occurred prior to or following the approximate time when a significant decline in food intake occurred. Plasma glucose levels decreased with tumor burden. Whole-blood lactate levels increased with tumor burden. Fasting plasma alanine levels decreased with tumor burden. Plasma 3-methylhistidine levels increased with tumor burden. Plasma glucagon levels increased with tumor burden, whereas plasma insulin levels decreased. Hormone changes were noted at small tumor burdens prior to a decline in food intake. Viable hepatocytes were isolated from 4 groups: non-tumor-bearing (NTB), small tumor burden [(STB) 3.5% total body weight (TBW)], moderate tumor burden [(MTB) 14% TBW], and large tumor burden [(LTB) 23% TBW]. As expected in NTB rats, hepatocytes produced significantly more glucose with 20 mM lactate than 20 mM alanine or than Hanks' balanced salt solution (HBSS) alone. Hepatocytes from STB rats demonstrated the same basic relationship for lactate, alanine, and HBSS, but they produced significantly more glucose from lactate and HBSS alone than NTB hepatocytes. With alanine as substrate, the rates of glucose production by hepatocytes were not affected by the presence or size of tumor. However, with lactate as substrate, hepatocytes from MTB and LTB rats produced progressively less glucose as tumor burden increased (r = -0.85, p less than .001), which may partly explain the reduction in blood glucose and elevation in blood lactate levels observed. Elevated gluconeogenesis in TB rats occurred early prior to a decline in food intake. The key precursor appeared to be lactate. The balance between glucagon and insulin appeared to promote the abnormal host carbohydrate metabolism observed.

Insulin protects against hepatic bioenergetic deterioration induced by cancer cachexia: an in vivo 31P magnetic resonance spectroscopy study.

The bioenergetic effects of cancer cachexia on the livers of male Fischer rats inoculated with a methylcholanthrene-induced sarcoma were assessed using serial in vivo 31P magnetic resonance spectroscopy. Rats were randomized into three groups: tumor-bearing controls (n = 7); an insulin-treated group receiving 2 units/100 g body weight/day starting 21 days after implantation (n = 8); and a chronic insulin-treated group receiving insulin every day after implantation (n = 3). During the 32-day study, serial measurements of food intake, body weight, and tumor volume were taken, and 31P magnetic resonance spectroscopy analyses of the livers were conducted every 7 days after tumor implantation. Neither the short-term nor the chronic insulin treatment regimens stimulated the progress of tumor growth. However, both treatments prevented body weight loss, and the short-term insulin treatment prevented tumor-induced decrease in food intake relative to the control group. Liver bioenergetic deterioration was evaluated from the increase in the ratio of Pi to ATP obtained from the hepatic 31P magnetic resonance spectra. At day 28 postimplantation, control rats exhibited appreciable hepatic bioenergetic deterioration, i.e., a Pi/ATP ratio of 1.41 +/- 0.35 (SE), significantly higher (P < 0.05) than the Pi/ATP ratio for short-term or chronic insulin treatment groups (Pi/ATP 0.92 +/- 0.22 and 0.84 +/- 0.22, respectively) or rats before tumor implantation (Pi/ATP 0.76 +/- 0.14). This insulin-induced bioenergetic protection occurred at any given tumor burden up to at least 10%. Thus, both short-term insulin given just prior to the frank manifestations of cancer cachexia and chronic insulin treatment given throughout tumor growth ameliorated host hepatic bioenergetic deterioration without significantly stimulating tumor growth. Insulin may act by altering the host metabolism (stimulation of liver glucose uptake and utilization, decreased energy-requiring gluconeogenesis, and general protein-sparing action) at the expense of the tumor.

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.

Altered leucine metabolism in noncachectic sarcoma patients.

Leucine and whole body protein metabolism were quantitated in 26 human subjects (6 sarcoma patients, 20 age-matched normal controls) using a primed, continuous infusion of [13C]leucine. Plasma samples were analyzed every 15 min for enrichment of [13C]leucine. Plateau enrichment levels were then used to calculate whole-body protein turnover, synthesis, and breakdown rates. Exhaled gas samples were analyzed every 15 min for enrichment of 13CO2, and plateau enrichment levels (as well as CO2 production rates) were used to calculate leucine oxidation rates. Fasting plasma amino acid levels, serum albumin, and total protein levels were also determined. The 6 patients were otherwise healthy but had a large, localized high-grade sarcoma which had not been previously treated. No patient had weight loss. Amino acid, albumin, and total protein levels were equivalent in patients and controls. Whole-body protein turnover rates were significantly greater in sarcoma patients than age-matched controls (15%). Increased protein turnover rates resulted in increased whole-body protein synthesis and breakdown rates in sarcoma patients compared to controls. Leucine oxidation rates were not different in the 2 groups. The results suggest that in humans with high-grade sarcomas leucine metabolic abnormalities are specific to tumor growth and not malnutrition because abnormalities of turnover, synthesis, and breakdown occur prior to any weight loss or measurable change in blood amino acid or protein level.

The effects of ingested and intravenous glucose on forearm uptake of glucose and glucogenic substrate in normal man.

The forearm uptake of glucose, lactate, and alanine was determined in overnight fasted man following both oral glucose loading and the intravenous (i.v.) infusion of glucose in an absorption pattern. Arterial glucose concentrations were lower following oral than following i.v. loading and forearm glucose uptake was 50% higher after oral glucose. Arterial insulin levels were higher in the first 2 h during oral loading. Forearm lactate and pyruvate production did not change significantly during glucose administration by either route so that the increased plasma levels are due to splanchnic production.

Usefulness of Ki-67, Mitoses, and Tumor Size for Predicting Metastasis in Carcinoid Tumors of the Lung: A Study of 48 Cases at a Tertiary Care Centre in Canada.

Background. Evaluation of Ki-67 index in lung carcinoid tumors (LCTs) has been of interest in order to identify high risk subsets. Our objectives are (1) to evaluate the usefulness of Ki-67 index, mitoses, and tumor size in predicting metastasis and (2) to compare the Manual Conventional Method (MCM) and the Computer Assisted Image Analysis Method (CIAM) for Ki-67 calculation. Methods. We studied 48 patients with LCTs from two academic centres in Canada. For Ki-67 calculation, digital images of 5000 cells were counted using an image processing software and 2000 cells by MCM. Mitoses/10 HPF was counted. Results. We had 37 typical carcinoids (TCs) and 11 atypical carcinoids (ACs). 7/48 patients developed metastasis. There was a positive relationship between metastasis and carcinoid type (P = 0.039) and metastasis and mitoses (≥2) (P = 0.017). Although not statistically significant, the mean Ki-67 index for ACs was higher than for TCs (0.95% versus 0.72%, CIAM, P = 0.299). Similarly, although not statistically significant, the mean Ki-67 index for metastatic group (MG) was higher than for nonmetastatic group (NMG) (1.01% versus 0.71% by CIAM, P = 0.281). However when Ki-67 index data was categorized at various levels, there is suggestion of a useful cutoff (≥0.50%) to predict metastasis (P = 0.106, CIAM). A significantly higher proportion of patients with mitosis ≥2 and Ki-67 index ≥0.50% had metastasis (P = 0.033) compared to other patients. Similarly patients with tumor size ≥3 cm and Ki-67 ≥0.50% had a greater percentage of metastases than others (P = 0.039). Although there was a strong correlation between two (MCM versus CIAM) counting methods (r = 0.929, P = 0.001), overall the calculated Ki-67 index was slightly higher by MCM (range 0 to 6.4, mean 1.5) compared to CIAM (range 0 to 2.9, mean 0.75). Conclusion. This study confirms that mitoses ≥2 is a powerful predictor of metastasis in LCTs. Although this is a small sample size, there is suggestion that analysis of Ki-67 index along with mitoses and tumor size may be a useful adjunct for predicting metastasis in LCTs.

Acute airway obstruction secondary to bilateral broncholithiasis.

We report a case of acute airway obstruction secondary to bilateral broncholiths. Successful management was achieved with rigid bronchoscopy.

Insulin decreases muscle protein loss after operative trauma in man.

Seventy-two hours after major operative trauma, nine patients receiving a constant infusion of calories (1460 kcal/m2/day) and protein (75 gm of amino acid/m2/day) showed a negative nitrogen balance, increased muscle catabolism, as measured by 3-methylhistidine excretion, increased amino acid efflux from muscle, and decreased circulating levels of insulin. When 5 U of insulin/hr were added to the infusate, arterial insulin levels rose significantly from 39.7 +/- 4.1 microU/ml to approximately the pretrauma levels (74.6 +/- 7.7 microU/ml). Despite this normalization of insulin levels, excretion of nitrogen and 3-methylhistidine and the efflux of amino acids from forearm muscle fell but did not return to pretraumatic levels, suggesting some insulin resistance. Visceral gluconeogenesis from amino acids appeared to decrease, since insulin infusion decreased the efflux of alanine from skeletal muscle with no change in its arterial level. Insulin also significantly reduced the efflux of isoleucine, tyrosine, phenylalanine, glutamine, and total amino acid nitrogen from forearm muscle. These findings, along with the partial reduction in the excretion of 3-methylhistidine and nitrogen, suggest that insulin, in combination with infused calories and protein, decreases the loss of muscle protein after trauma.

Major operative trauma increases peripheral amino acid release during the steady-state infusion of total parenteral nutrition in man.

The effect of major operative trauma on skeletal muscle metabolism was examined in nine patients receiving a constant infusion of calories (1460 kcal/m2/day) and protein (75 gm of amino acids/m2/day) for 5 days before and 4 days after an operation. Compared with the preoperative state, 72 hours after the operation there was a significant rise in arterial levels of glucagon, cortisol, norepinephrine, and inactive triiodothyronine and a drop in concentrations of insulin, active triiodothyronine, and amino acids. Forearm blood flow increased, as well as the efflux from forearm muscle of lactate, taurine, serine, glycine, valine, methionine, isoleucine, leucine, phenylalanine, lysine, arginine, and total amino acid nitrogen (440%). This loss of muscle protein after trauma is associated with increased muscle proteolysis, as measured by increased urinary 3-methylhistidine excretion (83%), and accounts for increased nitrogen loss (54%) from the body. Increased activity of the sympathetic nervous system is manifested by increased levels of epinephrine and norepinephrine, a relative lack of insulin, and increased levels of glucagon. This hormonal milieu plays an important role in the production of hypoaminoacidemia, increased efflux of amino acids and lactate from muscle, and negative nitrogen balance observed in these traumatized patients.

Resting energy expenditure and body cell mass alterations in noncachectic patients with sarcomas.

Resting energy expenditure (REE), body cell mass (BCM), and body fat (BF) were measured in six male and seven female volunteers and in a homogeneous group of noncachectic patients with sarcoma, (n = 7). The patients all had large localized tumors, no history or clinical evidence of decreased food intake or weight loss, and had received no prior treatment for cancer. Indirect calorimetry (for REE), K40 analysis (for BCM), and anthropometric measurements (for BF) were performed in accordance with established methods. Physical activity and nutritional status were also assessed. As expected, female control subjects had 50% greater percent BF (p less than 0.001) and 13% less percent BCM (p less than 0.01) than male controls. Male patients with sarcoma had equivalent percent BF, but significantly less percent BCM than controls matched for age, sex, and body surface area (BSA) (p less than 0.05). The REE corrected for BSA was similar in male and female controls but was 25% greater in male sarcoma patients than in male controls (p less than 0.05). This difference was doubled when REE was corrected for BCM (p less than 0.01). In patients with sarcomas, REE/BSA varied inversely with percent BCM (r = -0.782; p less than 0.05) while a similar relationship was not observed in healthy volunteers. We conclude that both REE and vital, functional BCM can be significantly altered in sarcoma patients before any overt signs of cachexia develop. The results support the contention that sarcoma alters host energy metabolism and causes abnormal body composition.

Transhiatal esophagectomy for carcinoma of the esophagus and cardia. Experience with 160 cases.

We reviewed our experience from 1979 to 1990 with 160 cases of transhiatal esophagectomy for carcinoma of the lower esophagus and cardia to evaluate trends in patient selection, management, and outcome. Patients treated in the past 6 years (n = 110) and those treated before 1985 (n = 50) were similar in terms of age and sex distribution, medical history, and weight loss. The majority of tumors seen were adenocarcinoma, with patients in the latter group having significantly lower stages. Significant decreases in anesthetic time, units of blood transfusions, chest tube insertions, length of postoperative ventilation, incidence of postoperative pneumonia, and length of hospital stay were seen during the past 6 years. Wound infections increased significantly during the same period. The decrease in the 30-day mortality rate from 6% to 0.9% was not significant. Survival rates did not differ between groups, with overall rates of 62%, 40%, and 21% at 1, 2, and 5 years, respectively.

Unsuspected metastatic choriocarcinoma presenting as unilateral spontaneous pneumothorax.

Spontaneous pneumothoraces are usually caused by subpleural apical blebs but may also be secondary to metastasis to the lung. We present the case of a 20-year-old woman with spontaneous pneumothorax secondary to choriocarcinoma metastatic to the lung.

Job's syndrome: a rare cause of recurrent lung abscess in childhood.

A clinical syndrome characterized by recurrent staphylococcal infection of the skin and respiratory tract from birth was described in 1966 and referred to as Job's syndrome. Marked hyperimmunoglobulinemia E was later found to be associated with this syndrome. This article describes a case of Job's syndrome as a cause of recurrent lung abscess during childhood necessitating lung resection.

Evaluation of noninvasive tests for the preoperative staging of carcinoma of the esophagus: a prospective study.

A prospective study was undertaken to define the usefulness of conventional full-lung linear tomography, radionuclide liver plus spleen and bone scans, and thoracic and abdominal computed tomography for the preoperative staging of carcinoma of the esophagus. Thirty-three patients with carcinoma of the esophagus were studied. The computed tomographic (CT) scan of the thorax and upper abdomen was the single most accurate noninvasive study. With computed tomography, the relationship of the tumor to the tracheobronchial tree was the feature most useful in predicting local resectability. In all patients with the finding of tracheobronchial compression by the tumor, the tumor could not be resected completely. The predictive value of this CT finding in patients with locally unresectable tumor was high (0.83), indicating its usefulness in assessing unresectability. The CT finding of visible separation between tumor mass and tracheobronchial tree was present in 10 of 14 patients with locally resectable tumor (predictive value, 0.63). However, tumor abutting the tracheobronchial tree without compression was a poor predictor of unresectability (predictive value, 0.36). The radionuclide bone scan was the only other noninvasive study to demonstrate a metastasis not evident by CT scan. The combination of chest and abdominal CT scan, bone scan, and bronchoscopy before operation will accurately stage the majority of patients with esophageal cancer but no noninvasive test is of sufficient reliability to exclude patients from operative resection if otherwise indicated.

A new technique for delivering the stomach or colon to the neck following total esophagectomy.

After total esophagectomy, swallowing is usually restored by stomach or colon interposed to the neck. The use of a new technique to facilitate the passage of these conduits to the neck for anastomosis to the cervical esophagus is described.

Propranolol for the prevention of postoperative arrhythmias in general thoracic surgery.

BACKGROUND: Prevention of postoperative arrhythmias in patients undergoing general thoracic surgery is desirable to prevent morbidity. METHODS: A randomized, double-blind, placebo controlled trial of propranolol (10 mg every 6 hours) for 5 days was undertaken in patients undergoing major thoracic operations to determine whether arrhythmias requiring treatment could be reduced. Secondary outcomes included overall arrhythmia rate, adverse events, and length of stay. Arrhythmias were assessed by 72-hour Holter monitoring. Patients with a history of heart failure, asthma, advanced heart block, preexisting arrhythmias, sensitivity to propranolol, or use of antiarrhythmic drugs were excluded. RESULTS: Using the intention-to-treat principle there was a 70% relative risk reduction from 20% to 6% in the rate of treated arrhythmias with propranolol (p = 0.071, 95% confidence interval 0.6% to 27.2%). Overall arrhythmias were common but usually benign. Adverse effects were common, although generally mild with hypotension and bradycardia being reported more often in the propranolol group. Length of stay was not different. CONCLUSIONS: There was a trend to a reduction in the risk of perioperative arrhythmias with propranolol. Moreover, propranolol was well tolerated showing a slight increase in minor adverse events.

Surgeons' assessment of symptoms suggesting extrathoracic metastases in patients with lung cancer. Canadian Lung Oncology Group.

BACKGROUND: In patients with apparently operable non-small cell lung cancer (NSCLC), clinicians often omit investigation for M disease in asymptomatic patients. Previous investigations have not specified in detail what is meant by "symptomatic," and this could differ between surgeons. We have investigated the extent to which surgeons' criteria differ for presence of symptoms. METHODS: Participating surgeons from seven centers, enrolled patients they judged "asymptomatic" in a randomized trial of investigational strategies for NSCLC. Patients completed a structured questionnaire describing symptoms of the central nervous system (CNS). In 685 patients, we documented CNS symptom recurrence after resectional surgery over 1 year of follow-up. RESULTS: Two centers enrolled only patients without even the mildest symptoms. Three centers took an intermediate approach, occasionally classifying patients with mild symptoms as "asymptomatic" and thus enrolling them in the trial. Two centers classified an appreciable number of patients with minimal symptoms, and occasionally with more than minimal symptoms, as "asymptomatic." Patients with even mild CNS symptoms were more likely to subsequently present with CNS metastases. CONCLUSIONS: Thoracic surgeons differ in their ideas of what may constitute the symptoms of M disease. Patients with structured questionnaire results that suggest symptoms of CNS disease are more likely to have CNS symptom recurrence after resectional surgery.

Pancreatic endocrine responses to nutrients and bombesin after segmental pancreas autotransplantation in dogs.

The capacity of autotransplanted (ATP) distal pancreas segments with systemic venous and peritoneal exocrine drainage to support physiologic control of plasma glucose levels was tested, and compared with the functions of "simulated autotransplants" (SATP) prepared with similar dissection and peritoneal exocrine drainage, but with hepatic portal venous drainage, in dogs. In ATP in the postabsorptive state, plasma levels of glucose, immunoreactive insulin (IRI) and immunoreactive glucagon (IRG1) were normal. Autotransplants resulted in impaired glucose tolerance after meals with impaired early insulin responses, and the normal brisk rise of IRG1 in the plasma was delayed and reduced through the first 30 min of feeding. In ATP, also, the response to bombesin was abnormal; the normal stimulation of release of both IRI and IRG1 was delayed in both cases. In studies of responses to oral and intravenous glucose in ATP and SATP dogs, similar mild degrees of glucose intolerance were found with both routes of administration; however, whereas in ATP dogs increases of IRI were highly exaggerated with both routes of administration of glucose, in SATP dogs plasma IRI rose from subnormal levels in the postabsorptive state through subnormal increments with both routes of administration. Further studies are necessary to determine the relative importance of denervation and reduction of the mass of the pancreas in these effects, and to assess the significance of the differences in blood insulin levels in the two preparations.