Complete Pathologic Response after Combined Modality Treatment for Rectal Cancer and Long-Term Survival: A Meta-Analysis

Background

Complete pathologic response (CPR) after neoadjuvant chemoradiotherapy (combined modality treatment, CMT) for rectal cancer seems associated with improved survival compared to partial or no response (NPR). However, previous reports have been limited by small sample size and single-institution design.

Methods

A systematic literature review was conducted to detect studies comparing long-term results of patients with CPR and NPR after CMT for rectal cancer. Variables were pooled only if evaluated by 3 or more studies. Study end points included rates of CPR, local recurrence (LR), distant recurrence (DR), 5-year overall survival (OS), and disease-free survival (DFS).

Results

Twelve studies (1,913 patients) with rectal cancer treated with CMT were included. CPR was observed in 300 patients (15.6%). CPR and NPR patient groups were similar with respect to age, sex, tumor size, distance of tumor from the anus, and stage of disease before treatment. Median follow-up ranged from 23 to 46?months. CPR patients had lower rates of LR [0.7% vs. 2.6%; odds ratio (OR) 0.45, 95% confidence interval (CI) 0.22?C0.90, P?=?0.03], DR (5.3% vs. 24.1%; OR 0.15, 95% CI 0.07?C0.31, P?=?0.0001), and simultaneous LR?+?DR (0.7% vs. 4.8%; OR 0.32, 95% CI 0.13?C0.79, P?=?0.01). OS was 92.9% for CPR versus 73.4% for NPR (OR 3.6, 95% CI 1.84?C7.22, P?=?0.002), and DFS was 86.9% versus 63.9% (OR 3.53, 95% CI 1.62?C7.72, P?=?0.002).

Conclusions

CPR after CMT for rectal cancer is associated with improved local and distal control as well as better OS and DFS.     

Medical education about the care of addicted incarcerated persons: A national survey of residency programs

In June 1998, there were 1.8 million inmates in correctional facilities for adults; 1.2 million in state and federal prisons and 600,000 in municipal/county jails (668 persons per 100,000 U.S. population). Rates of TB, AIDS, mental illness, and substance abuse are 2–13 times higher in persons living in jails and prisons. This study was designed to assess the level of training offered to residents in seven medical specialties in the care of addicted incarcerated persons. The study design involved two stages. The first entailed a mailed survey to 1,831 residency directors in family medicine, internal medicine, osteopathic medicine, pediatrics, obstetrics and gynecology, psychiatry, and emergency medicine. The second stage was a telephone interview, about substance use disorders, of faculty listed by the residency directors as teaching residents. The mailed survey was completed by 1,205 residency directors (66%). The 769 faculty from those identified programs, who participated in the telephone interview, reported that only 14% of their residency programs offered lectures or conferences on the care of incarcerated persons, yet 44% of the programs had residents caring for incarcerated persons with substance abuse problems, in a clinical setting. Only 22% offered clinical experiences for residents in a correctional facility.

We recognize that our survey of correctional health and substance abuse training is limited, but as such, a greater number of respondents to our survey do not teach residents addiction medicine topics pertaining to prevention, evaluation, intervention, and management of the addicted criminal offender/patient in a correctional setting or give adequate clinical exposure to this special population. The data suggests a need to develop and implement educational programs on medical care for this high‐risk and expanding population.     

Vasculature of various locations of canine gastrointestinal tract responds differently to intravenous isoproterenol

In this study we investigated the relative vascular response of different locations of the gastrointestinal tract to continuous intravenous infusion of isoproterenol (0.1 microgram kg-1 min-1 for 10 min). The vascular response of some nonsplanchnic organs was also examined. Blood flow of the arteries was measured by electromagnetic flowmetry and that of the tissues by 15-micron microspheres. Isoproterenol increased (P less than 0.05) blood flow of the axillary artery (+52%), and the superior mesenteric artery (+45%), but not that of the inferior mesenteric artery. In the nongastrointestinal tissues, isoproterenol increased (P less than 0.05) the blood flow of the left (+46%), and right ventricle (+85%), and the skeletal muscle (+100%). In the gastrointestinal tract, isoproterenol increased (P less than 0.05) blood flow in the esophagogastric junction (+505%) and antrum (+1511%) only, but not in the gastric body or in any location of the small or large intestine. The drug also caused a large fall in resistance in the esophagogastric junction (-74%) and antrum (-94%), and a small, but significant fall in the duodenum, jejunum, and in the mid-small intestine. It had no significant effect on vascular resistance in the gastric body, ileum, or colon. In those locations of the gastrointestinal tract where isoproterenol caused an increase in blood flow, this effect was confined to the combined mucosal plus submucosal layer, and the drug had no effect on the muscularis. These data suggest that different locations of the gastrointestinal tract respond differently to the same circulating concentration of isoproterenol. The mechanism of this difference in response merits further investigation.(ABSTRACT TRUNCATED AT 250 WORDS)     

Anabolic therapy in primary osteoporosis

Antiresorptive therapy for osteoporosis has been a mainstay during the past 50 yr. But an entirely new class of agents known as anabolic drugs has recently been introduced. These drugs “grow new bone,” reconstitute the destroyed skeletal architecture of osteoporosis, and thereby reduce the risk of new fractures. Teriparatide is the first such drug to fulfill these requirements, but other agents look promising such as growth hormone and strontium renalate. On the horizon are native and analogs of parathyroid hormone also. But these are only the beginning of a vast array of possibilities, which will arise from an understanding of the regulatory pathways of osteoblast function. This review focuses on old and new agents, which are prospects for bone growth based on in vivo data from human or other animal studies. It covers drugs that are in use, or nearly so, and discusses a variety of potential target sites for future drug development.