Age-dependent metabolic effects of repeated hypoxemia in piglets

The aim of this study was to determine whether repeated exposure to hypoxemia would modify the response to hypoxemia during maturation. We exposed piglets to three 1-h cycles of hypoxemia (PaO2 = 30 to 35 mmHg; 1 mmHg = 133.3 Pa) at 1 week (n = 9), 2-3 weeks (n = 10), and 4-5 weeks of age (n = 10). O2 consumption (V(O2)) and CO2 production (V(CO2)) were measured, and alveolar ventilation (V(A)) was derived from V(CO2) and PaCO2. Levels of lactic acid (lactate) and serum catecholamines were also measured. With hypoxemia, time had a significant effect on V(O2) and body temperature in an age-dependent fashion: that is, whereas the 1 week group and the 4-5 week group showed both variables decreasing over time, the 2-3 week group showed no drop in V(O2) and a small increase in body temperature over time. Lactate levels increased with hypoxemia in all animals during the first exposure. However, with repeated exposures to hypoxemia, only the 2-3 week group continued to increase its lactate levels. Furthermore, the changes in lactate levels paralleled the changes in epinephrine levels with hypoxemia. We found, too, that although V(A) increased significantly with hypoxemia in all animals, this change was not modified by age or repeated exposures. No significant effects of age or repeated exposures were found in the cardiovascular response to hypoxemia. We concluded that, from a metabolic viewpoint, after repeated exposures to hypoxemia the 2-3 week animals responded differently.

Ethnic differences in knowledge and attitudes about BRCA1 testing in women at increased risk

Informed consent for BRCA1 mutation testing will require adequate knowledge of patterns of inheritance of cancer and the benefits, limitations, and risks of DNA testing. This study examined knowledge about the inheritance of breast cancer and attitudes about genetic testing for breast-ovarian cancer susceptibility in women at increased risk. Knowledge and attitudes were measured in 407 African American and Caucasian women aged 18-75 who had at least one first-degree relative (FDR) with breast and/or ovarian cancer. The average knowledge score was 6.0 out of a total of 11 (S.D. = 2.15). Compared to Caucasian women, African American women had lower levels of knowledge and had more positive attitudes about the benefits of genetic testing. There were no significant ethnic differences in attitudes about the limitations and risks of testing, however, income was negatively associated with this outcome. Ethnic differences in knowledge and attitudes about genetic testing for breast-ovarian cancer risk may be attributable to differences in exposure to genetic information and referral by health care providers.

Phase I trial of a novel matrix metalloproteinase inhibitor batimastat (BB-94) in patients with advanced cancer

Degradation of basement membrane and extracellular matrix by matrix metalloproteinases (MMPs) is believed to be required for tumor invasion, tumor-induced angiogenesis and vascular invasion. A synthetic hydroxamate, batimastat (also known as BB-94), inhibits MMPs by binding the zinc ion in the active site of the MMP. Batimastat inhibits at least 50% of MMP activity at concentrations less than or equal to 10 ng/ml in vitro. Batimastat retarded ascites accumulation and increased survival in mice with human ovarian tumor xenografts. Acute and long-term toxicological studies revealed no major toxicity in animals. Batimastat is poorly soluble and was administered intraperitoneally (i.p.) as a suspension. Previous studies in patients with malignant ascites have shown no major toxicities at doses as high as 1350 mg/m2.

Intraperitoneal therapy administered through a Groshong catheter

This report describes a new device for delivery of intraperitoneal therapy. From October 1989 through March 1991, 27 externally accessed Groshong (Bard Access Systems, UT) catheters were placed transabdominally into 24 patients with presumed epithelial ovarian cancer at the conclusion of primary or second-look laparotomy. Total duration of catheter use was 81 months (range, 1-62 weeks). Fifty-seven cycles of intraperitoneal therapy were administered through 18 catheters (range, 1-11). Nine catheters were removed without being used after patients randomized off intraperitoneal treatment arms or were ineligible for intraperitoneal protocols. There were no complications associated with catheter placement or removal. None of the catheters became obstructed or dislodged while in place. There were no cases of infectious peritonitis, although one patient developed an exit-site skin infection. Surgery is not required to remove the Groshong catheter which fosters empiric placement of the device at the time of laparotomy in all patients potentially eligible for intraperitoneal therapy. The device-related infection rate of 4.2 per 100 patients is similar to that described using other implanted devices. Catheter maintenance is easy and patient acceptance is good. The Groshong catheter is a safe, reliable, and acceptable means of delivering intraperitoneal therapy.

Reverse hysterocolposigmoidectomy (RHCS) for resection of panpelvic tumors

Lateral retroperitoneal approaches to abdominopelvic masses are commonly employed; the reverse hysterocolposigmoidectomy (RCHS) in addition utilizes transabdominal entry of the vaginal and rectovaginal spaces to provide medial access to the uterosacral and cardinal ligaments as well expose a tumor-free segment of the rectosigmoid for en bloc resection of panpelvic tumors. Thirty-one patients underwent reverse hysterocolpectomy for extensive, symptomatic pelvic malignancies. All patients had complete resection of pelvic tumor, and there were no perioperative deaths. Sigmoid resection was required in 25 patients with 22 primary reanastomosis and 3 end colostomies performed. In 6 patients, vaginal entry facilitated tumor resection while sparing the rectosigmoid. Average operative blood loss was 2677 cc. Early postoperative morbidity (1-30 days) occurred in 13 patients; febrile morbidity (6 patients) was the common complication. Late morbidity (1-6 months) was seen in 10 patients, including 1 fatal pulmonary embolism at 5 months. Subsequent therapy was tolerated well. Mean survival/follow-up is 15.7 months (range, 1 to 49 months). Seventeen patients are alive, seven patients without evidence of disease (average 13.4 months), and ten patients are alive with disease (average follow-up, 28.3 months). Thirteen patients are dead of disease or complication (average survival, 13.7 months). We conclude that RHCS facilitates resection of extensive pelvic tumors with acceptable morbidity.

Manometric characterization of rectal dysfunction following radical hysterectomy

Bladder dysfunction thought to be due to partial denervation has been described following radical hysterectomy. Some patients experience acute and chronic rectal dysfunction characterized by difficulty with defecation and loss of defecatory urge. To define this abnormality, anorectal pressure profiles were examined in 15 patients with Stage I carcinoma of the cervix before and after radical hysterectomy. Profiles were done using standard anorectal manometry with a water-infused system. In all patients preoperative manometric profiles were normal; postoperative studies were abnormal in all patients. Features seen include altered relaxation of the internal sphincter, increased distension needed to trigger relaxation, and decreased rectal sensation; external sphincters and resting internal sphincters were unchanged. Postoperatively, 12 patients reported problems with rectal function. A physiologic defect is definable in patients undergoing radical hysterectomy; this suggests disruption of the spinal reflex arcs controlling rectal emptying. These physiologic abnormalities correlate with the clinical symptomatology experienced by some patients. Continuing definition and evaluation of management options in this situation should be useful in developing effective therapy for rectal dysfunction following radical hysterectomy.

Postoperative adjuvant external-beam radiotherapy in surgical stage I endometrial carcinoma

A combined surgical and radiotherapeutic approach is widely in Stage I endometrial adenocarcinoma. The technique and timing of the radiotherapy varies from center to center. Postoperative external-beam (EB) radiotherapy has the advantage of patient selection based upon surgical findings, comprehensive treatment of the pelvic nodal and vaginal cuff areas, and elimination of the need for an intracavitary procedure. Although frequently utilized, this technique is surprisingly poorly described in the medical literature. From 1979 to 1986, 46 surgical Stage I patients received adjuvant postoperative EB therapy at Georgetown University Hospital (GUH) (Washington, DC). Indications for treatment were Grade greater than or equal to 2 and/or depth of myometrial invasion of greater than 33%. The 5-year actuarial survival was 90% with a disease-free survival of 82%. The failure rate within the irradiated field was 6.5% with a distant failure rate of 8.7%. The rate of significant long-term complications was acceptable at 6.5%. The authors conclude that postoperative EB radiotherapy is an effective adjuvant therapy with results comparable to other available radiotherapeutic techniques.