Retreating recurrent breast cancer with the same CMF-containing regimen used as adjuvant therapy. The International Breast Cancer Study Group

Breast cancer metastases appearing soon after adjuvant chemotherapy (within 12 months of its completion) are usually resistant to retreatment with the same cytotoxic agents, while relapses occurring later (beyond 12 months) regress when rechallenged with the same agents, showing similar response rates observed in non-pretreated patients with advanced disease. The International Breast Cancer Study Group (IBCSG) prospectively explored the efficacy of retreatment for patients upon relapse using the same therapy administered during the adjuvant programme. 87 patients previously treated with an adjuvant CMF (cyclophosphamide, methotrexate, 5-fluorouracil) combination chemotherapy (with or without the addition of low-dose prednisone and tamoxifen), who had measurable first breast cancer relapse, usually after at least 6 months of completion of the adjuvant treatment, were treated with CMF. Pretreatment consisted of 1-3 CMF courses in 27 patients and 4 or more courses in 60 patients. 17 patients were retreated with additional tamoxifen or had tamoxifen stopped at relapse. The data of these patients are shown separately. 47 of the 86 fully evaluable patients (55%) had an objective response, which was complete in 25 (29%). The dominant metastatic type and the number of involved sites were the most important factors influencing response to retreatment. Patients with soft tissue metastases had a high response rate (36/52, 69%) compared with those who had visceral involvement (9/24, 38%) or those with bony disease (2/10, 20%) (P = 0.002). In conclusion, response rates to retreatment with CMF were similar to those expected in a non-pretreated population. The patterns of relapse and the number of metastatic sites were the most important factors predicting response to retreatment, while treatment-free interval (usually longer than 6 months due to the study design) did not influence response rates. This study supports the hypothetic effectiveness of late reintroduction of adjuvant cytotoxic therapy (prior to evidence of systemic relapse), upon which several current trials are based.

Development of a radiology faculty appraisal instrument by using critical incident interviewing

RATIONALE AND OBJECTIVES

To develop a valid and reliable radiology faculty appraisal instrument based on scientific methods.

MATERIALS AND METHODS

Fifteen radiology residents participated in critical incident interviewing. During a 1-hour interview, a resident was asked to describe five incidents each of effective and ineffective faculty behavior. Two investigators independently listened to the tape-recorded interviews, and two different investigators sorted the incidents into broad categories. A faculty appraisal instrument was developed by listing similar incidents under broad categories. A five-point rating scale was applied to each item. Content validity was assessed by resident and faculty critique of the appraisal instrument.

RESULTS

A total of 168 incidents of faculty behavior were generated. The frequency with which similar incidents were reported was recorded. The most common behaviors reported were related to staff expertise and teaching. Interjudge reliability was good, as determined by computing K indices of agreement (overall K = 0.59). There was good agreement regarding instrument content validity among residents but not among faculty.

CONCLUSION

Residents supported the use of the new appraisal instrument, but further tests of validity and reliability and faculty acceptance of the instrument will determine its usefulness as a tool for monitoring faculty teaching performance and making decisions regarding faculty promotion.

The use of condoms with other contraceptive methods among young men and women

In a nationally representative sample of sexually experienced youths aged 14-22, 37% of young women and 52% of young men said the condom was the primary method used to prevent pregnancy at last intercourse; an additional 8% and 7%, respectively, said they used a condom at last intercourse; much of this represents dual use [corrected]. Condom use at last intercourse was reported by 25% of young men whose partner was using the pill. Significant independent predictors of condom use with the pill among men included younger age, black race, engaging in fewer nonsexual risk behaviors and having received instruction about HIV in school. Among young women, 21% of those relying on the pill reported also using a condom at last intercourse. For women, independent predictors of dual use included younger age, black race, older age at first sex, fewer nonsexual risk behaviors, having no partners in the previous three months and having talked to parents or other adult relatives about HIV.

Resident learning and knowledge retention from resident-prepared chest radiology conferences

RATIONALE AND OBJECTIVES

The authors assessed resident learning and retention of knowledge from resident-prepared chest radiology conferences.

MATERIALS AND METHODS

Radiology residents presented five chest conferences to their peers during a 5-month interval; the conferences were modeled on a case presentation format. Tests were given 5 minutes before each conference (pretest) and immediately after each conference (posttest). The tests were readministered as a final examination 6 months later, at which time the residents were asked to evaluate the conference format.

RESULTS

Conference attendance ranged from six to 11 residents. Mean posttest scores were statistically significantly higher than mean pretest scores (P < .0001). Six-month retention scores were higher than pretest scores (P < .05) but lower than posttest scores (P < .05). On a scale of 1-6, with 1 representing strongly disagree and 6 strongly agree, residents strongly agreed that the conferences provided an excellent learning experience (mean score, 5.27).

CONCLUSION

Resident-prepared conferences are effective for teaching residents chest radiology. Resident testing at 6 months demonstrated retention of knowledge above pretest levels but lower than posttest levels.

Design of sensitive fluorogenic substrates for human cathepsin D

Cathepsin D is a lysosomal aspartic proteinase that has been implicated in several pathological processes such as breast cancer and Alzheimer's disease. We designed and synthesized a number of quenched fluorogenic substrates with P2 variations in the series AcEE(EDANS)KPIXFFRLGK(DABCYL)E-NH2, where X=cysteine, methylcysteine, ethylcysteine, tert-butylcysteine, carboxymethylcysteine, methionine, valine or isoleucine. Most of the fluorogenic substrates exhibited greater k(cat)/Km ratios than the best cathepsin D substrates described so far. Differences in kinetic constants, which were rationalized using structure-based modeling, might make certain substrates useful for particular applications, such as active site titrations or initial velocity determination using a fluorescent plate reader.

Accelerated titration designs for phase I clinical trials in oncology

BACKGROUND

Many cancer patients in phase I clinical trials are treated at doses of chemotherapeutic agents that are below the biologically active level, thus reducing their chances for therapeutic benefit. Current phase I trials often take a long time to complete and provide little information about interpatient variability or cumulative toxicity.

PURPOSE

Our objective was to develop alternative designs for phase I trials so that fewer patients are treated at subtherapeutic dose levels, trials are of reduced duration, and important information (i.e., cumulative toxicity and maximum tolerated dose) needed to plan phase II trials is obtained.

METHODS

We fit a stochastic model to data from 20 phase I trials involving the study of nine different drugs. We then simulated new data from the model with the parameters estimated from the actual trials and evaluated the performance of alternative phase I designs on this simulated data. Four designs were evaluated. Design 1 was a conventional design (similar to the commonly used modified Fibonacci method) using cohorts of three to six patients, with 40% dose-step increments and no intrapatient dose escalation. Designs 2 through 4 included only one patient per cohort until one patient experienced dose-limiting toxic effects or two patients experienced grade 2 toxic effects (during their first course of treatment for designs 2 and 3 or during any course of treatment for design 4). Designs 3 and 4 used 100% dose steps during this initial accelerated phase. After the initial accelerated phase, designs 2 through 4 resorted to standard cohorts of three to six patients, with 40% dose-step increments. Designs 2 through 4 used intrapatient dose escalation if the worst toxicity is grade 0-1 in the previous course for that patient.

RESULTS

Only three of the actual trials demonstrated cumulative toxic effects of the chemotherapeutic agents in patients. The average number of patients required for a phase I trial was reduced from 39.9 for design 1 to 24.4, 20.7, and 21.2 for designs 2, 3, and 4, respectively. The average number of patients who would be expected to have grade 0-1 toxicity as their worst toxicity over three cycles of treatment is 23.3 for design 1, but only 7.9, 3.9, and 4.8 for designs 2, 3, and 4, respectively. The average number of patients with grade 3 toxicity as their worst toxicity increases from 5.5 for design 1 to 6.2, 6.8, and 6.2 for designs 2, 3, and 4, respectively. The average number of patients with grade 4 toxicity as their worst toxicity increases from 1.9 for design 1 to 3.0, 4.3, and 3.2 for designs 2, 3, and 4, respectively.

CONCLUSION

Accelerated titration (i.e., rapid intrapatient drug dose escalation) designs appear to effectively reduce the number of patients who are under-treated, speed the completion of phase I trials, and provide a substantial increase in the information obtained.

Menstrual cycle and timing of breast surgery in premenopausal node-positive breast cancer: results of the International Breast Cancer Study Group (IBCSG) Trial VI

PURPOSE

It has been postulated that breast cancer surgery performed during the follicular phase of the menstrual cycle is associated with poorer outcome.

PATIENTS AND METHODS

We tested this hypothesis by evaluating disease-free survival (DFS) for 1033 premenopausal patients who received definitive surgery either during the follicular phase (n = 358) or the luteal phase (n = 675). All patients were enrolled in a randomized trial conducted between July 1986 and April 1993. All had node positive breast cancer and randomization was stratified by estrogen receptor (ER) status. All patients received at least three cycles of adjuvant cyclophosphamide, methotrexate, and 5-fluorouracil (CMF). The median follow-up was 60 months.

RESULTS

Patients who underwent definitive surgery for breast cancer in the follicular phase had a slightly worse disease-free survival than those operated on during the luteal phase (five-year DFS percentage: 53% versus 58%; hazard ratio, 1.13; 95% confidence interval (CI), 0.94-1.38; P = 0.20). The effect was significantly greater for the subpopulation of 300 patients with ER-negative primaries (P = 0.02 interaction effect; five-year DFS percentages 42% vs. 59%; hazard ratio 1.60; 95% CI, 1.12-2.25; P = 0.008). The effect of timing of surgery diminished for analyses based on lesser surgical procedures, e.g., excisional biopsies. In particular, no effect of timing was observed for fine needle aspiration procedures.

CONCLUSIONS

Surgical procedures which are more extensive than a fine needle aspiration biopsy might be associated with worse prognosis if conducted during the follicular phase of the menstrual cycle. This phenomenon was seen predominantly for high risk breast cancer with low levels or no estrogen receptors in the primary tumor.

Design factors in epidemiologic cohort studies of work-related low back injury or pain

The connection between work-related exposures and the onset of back injury or pain is complex and not clearly understood. This paper raises design issues related to the planning and conduct of cohort studies of industrial low back pain (or injury)(LBP), with care given to definition and measurement of exposure and outcome events. These issues include sample size, outcome definition, study biases, and practical considerations when seeking and maintaining company collaboration with a research effort. Without resolving these issues, the authors conclude: (1) cohort studies of worksite-based LBP are needed to elucidate the causal associations between work tasks and LBP onset, (2) both acute and cumulative exposures should be assessed as risk factors for low back injury or pain, and (3) attention should be paid to the planning of such studies and minimization of potential biases that can limit the validity of the results. These design issues will benefit researchers and companies engaged in the planning and conduct of cohort studies of industrial LBP.

Prospective evaluation of a stiff shaft glide wire compared with the standard straight wire in crossing severely stenotic aortic valves

In this prospective randomized study of the use of the Terumo glide wire compared with the standard straight wire for crossing of severely stenotic aortic valves, the glide wire was shown to significantly decrease the fluoroscopy time of the procedure and to lower by 3.4 times the need for crossover to the alternative technique.

Identification of a recombination event narrowing the Lafora disease gene region

Patients affected with progressive myoclonus epilepsy of the Lafora type present during late adolescence with a characteristic EEG pattern and Lafora bodies seen on skin biopsy. The critical region for the Lafora gene has been localised to chromosome 6q24 flanked by the dinucleotide repeat markers D6S292 and D6S420. This study for linkage of markers from the candidate gene region was performed in a previously unpublished family affected with Lafora disease. EEG and skin biopsy evaluation for Lafora bodies were performed on five of eight family members followed for seizure activity. Haplotype and linkage analysis of DNA from five family members were carried out using the nine dinucleotide repeat markers reported in the common region of homozygosity by Serratosa et al in 1995. The present study of an additional family affected by Lafora disease has narrowed the 17 cM critical region for the Lafora disease gene on chromosome 6q24 to a 4 cM region flanked by markers D6S308 and D6S311.

Alternating current electrocution detection and termination by an implantable cardioverter defibrillator

A patient with an ICD accidentally grasped a power line and was electrocuted. He was unable to release the cable during electrocution though he remained conscious. After receiving a shock from his ICD, the powerline was released. ICD interrogation revealed inappropriate detection of alternating current and delivery of a shock.

Experimental measles. II. Infection and immunity in the rhesus macaque

Measles infection and the host immune response to measles virus was compared using naive and immunized rhesus monkeys. The monkeys were experimentally challenged with a wild-type strain of measles virus inoculated intranasally. After pathogenic virus challenge, measles virus was detected in mononuclear cells of peripheral blood, lymph node, and spleen in naive monkeys and viremia peaked on Day 7. However, only one of five vaccinated monkeys had a lower virus titer in peripheral blood mononuclear cells at one time point after challenge. No virus was detected in the lymphoid tissues from an immunized monkeys that was euthanized on Day 7 of infection. Measles-specific IgM, IgG, neutralizing antibody, and cytotoxic T lymphocytes were detected in vaccinated monkeys before challenge, but antibody titers were significantly lower in immunized monkeys than in naive monkey after challenge. Measles-specific IgG antibody and cytotoxic T cell responses were still detected more than 1 year after vaccination or infection. This animal model is useful for the further study of measles pathogenesis, immunosuppression, and immunologic memories.