Patients undergoing recurrent CT exams: assessment of patients with non-malignant diseases,reasons for imaging and imaging appropriateness

To determine percent of patients without malignancy and ≤ 40 years of age with high cumulative radiation doses through recurrent CT exams and assess imaging appropriateness. From the cohort of patients who received cumulative effective dose (CED) of ≥ 100 mSv over a 5-year period, a sub-set was identified with non-malignant disease. The top 50 clinical indications leading to multiple CTs were determined. Clinical decision support (CDS) system scores were analyzed using a widely adopted standard of 1–3 (red) as “not usually appropriate,” 4–6 (yellow) “may or may not be appropriate,” and 7–9 (green) “usually appropriate.” Clinicians reviewed patient records to assess compliance with appropriate use criteria (AUC). 9.6% of patients in our series were with non-malignant conditions and 1.4% with age ≤ 40 years. CDS scores (rounded) were 2% red, 38% yellow, 27% green, and 33% unscored CTs. Clinical society guidelines for CT exams, wherever available, were followed in 87.5 to 100% of cases. AUCs were not available for several clinical indications as also referral guidelines for serial CT imaging. More than half of CT exams were unrelated to follow-up of a primary chronic disease. We are faced with a situation wherein patients in age ≤ 40 years require or are thought to require many CT exams over the course of a few years but the radiation risk creates concern. There is a fair number of conditions for which AUC are not available. Suggested solutions include development of CT scanners with lesser radiation dose and further development of appropriateness criteria.     

Distinguishing between periampullary carcinoids and carcinomas--is this possible preoperatively?

It is difficult to distinguish between carcinoid tumors of the pancreatic head and periampullary region and carcinomas preoperatively. Between 1996 and 2002, 125 consecutive pancreaticoduodenectomies done by us for periampullary tumors (14 carcinoids, 111 carcinomas) were analyzed. Patients with carcinoid tumors had significantly younger mean age (48 vs. 54 years), longer history (32 vs. 8 weeks), lower serum total bilirubin levels (1.4 vs. 6.3 mg/dL) and on CT scan, had larger, well-localized tumors (5 cm vs. 2 cm). Their postoperative course was better with no mortality or major morbidity, whereas after resection for carcinoma 7 (6.3%) patients died and 30 (27%) had major postoperative complications. Thus, a tumor of this region in a young patient with indolent history, low bilirubin level and with CT scan depicting a large expansile lesion suggests a carcinoid. Such tumors may be safely resected with low postoperative morbidity and mortality and good long-term prognosis.     

Combining Vaccines with Conventional Therapies for Cancer

Preclinical and clinical investigations currently underway are employing novel strategies for combining vaccines with conventional and experimental anticancer therapies. To date, the FDA has not approved a therapeutic cancer vaccine. However, the results of recent investigations suggest an increasing role for vaccines in new models of combination therapy for many types of cancer. This article reviews and discusses therapeutic cancer strategies that employ vaccines in combination with local radiation, chemotherapy, hormone therapy, and anti-CTLA-4 mAb. Preclinical studies have shown that certain anticancer agents have immune modulatory effects that result in up-regulation of surface expression of MHC molecules, tumor-associated antigens, or Fas on malignant cells, rendering them more susceptible to immune destruction. Preliminary results of clinical studies using combination strategies have demonstrated a postvaccination antigen cascade, prolonged time to disease progression, and improved overall survival. Several larger randomized trials are ongoing, and more are required to support these findings.     

Evaluation of specialized laparoscopic suturing and tying devices.

BACKGROUND: Laparoscopic suturing and tying constitute advanced minimally invasive surgery skills. Developing proficiency in the standard methods with needle drivers is often an arduous process. Recent advances in laparoscopic instrumentations has allowed for easier methods of suturing and tying. This study investigated the hypothesis that the use of a specialized suturing device and a specialized tying device allows inexperienced medical students to suture and tie laparoscopically. METHODS: Preclinical medical students who had not received any training in open or laparoscopic surgery were included in this investigation. Each student was given a 5-minute demonstration of a specialized suturing device and a specialized tying device. The medical students were not allowed to deploy either device before actual use. After the demonstration, each student was given the device to use in a porcine model. Times were recorded and a subjective grade was given for each student. RESULTS: Twenty medical students were involved in this study. All medical students were able to complete the task of suturing and tying. The average time to suture was 104.6 seconds and the average time to tying was 31.2 seconds. The average subjective performance grade was 90 (out of 100). CONCLUSION: Specialized devices are easy to learn and use for laparoscopic suturing and tying with minimal instruction even for inexperienced medical students. Even surgeons who are not well versed in laparoscopic surgery should be able to suture and tie with certain laparoscopic instruments.     

Acute renal and hepatic toxicity of 2-haloanilines in Fischer 344 rats.

Aniline and its halogenated derivatives are widely used as chemical intermediates. The purpose of this study was to determine the hepatotoxic and nephrotoxic potential of the 2-haloanilines. Male Fischer 344 rats (n > or = 4) were injected (i.p.) with 1.0 or 1.25 mmol/kg of: aniline (A), 2-fluoroaniline (2-FA), 2-chloroaniline (2-ClA), 2-bromoaniline (2-BrA), 2-iodoaniline (2-IA) or vehicle (0.9% saline, 2.5 ml/kg). All compounds were injected as hydrochloride salts. Renal and hepatic function was monitored 24 h after treatment. All of the 2-haloanilines induced oliguria, diminished kidney weight, tubular casts and decreased renal cortical slice accumulation of organic anions. Blood urea nitrogen (BUN) levels were increased (P < 0.05) by treatment with 1.0 or 1.25 mmol/kg of 2-FA, 2-ClA or 2-BrA. Hepatic alterations were also observed and characterized by elevated plasma ALT/GPT activity and altered morphology in the centrilobular region. The nephrotoxic and hepatotoxic potentials were similar among the 2-haloanilines but aniline was less toxic than its 2-halo derivatives. These results demonstrated that halogen substitution at the 2-position of aniline increased hepatic and renal toxicity. However, the severity of toxicity was not influenced by the nature of the halogen substituent.     

Cephaloridine nephrotoxicity in streptozotocin induced diabetic Fischer 344 (F344) rats

The purpose of this study was to determine if cephaloridine nephrotoxicity is attenuated in streptozotocin (STZ)-induced diabetic rats. Fischer 344 (F344) rats (205-250 g) were given a single injection (i.p.) of STZ (27-35 mg/kg) or citrate buffer. The nephrotoxicity of (750 mg/kg) cephaloridine (i.p.) was then compared with normoglycemic and 14-day diabetic rats. Increased blood urea nitrogen (BUN) levels as well as diminished renal cortical slice accumulation of tetraethylammonium (TEA) and lactate-stimulated p-aminohippurate (PAH) were measured (P less than 0.05) in normoglycemic rats 48 h after cephaloridine administration. Cephaloridine failed to alter BUN levels and organic ion accumulation in diabetic rats. Diabetes did not totally protect against cephaloridine toxicity since kidney weights were elevated in normoglycemic and diabetic rats 48 h after administration of 750 mg/kg cephaloridine. A series of experiments also measured BUN levels, kidney weight and renal cortical slice uptake of PAH and TEA 24, 48 and 72 h after (1500 mg/kg) cephaloridine administration. Cephaloridine increased (P less than 0.05) kidney wt and decreased PAH and TEA uptake (P less than 0.05) in the normoglycemic group at 24-72 h. No change in kidney wt, PAH or TEA uptake was observed in the diabetic rats. These data indicate diabetes reduces cephaloridine nephrotoxicity.