Search PubMed⌕ Search

Biomedical subjects

D A August

Publications and source records attributed to D A August.

At least 37 records · Page 2Linked to original sources
PubMed1995

Immediate transverse rectus abdominis musculocutaneous flap reconstruction after mastectomy.

BACKGROUND: This study examines the early and long-term outcomes of immediate transverse rectus abdominis musculocutaneous (TRAM) reconstruction of the breast after mastectomy. STUDY DESIGN: The records of all patients undergoing mastectomy and immediate TRAM breast reconstruction between December 1989 and October 1993 were reviewed retrospectively using hospital and breast care center databases. RESULTS: Fifty-three patients underwent a total of 73 immediate TRAM breast reconstructions. Reconstruction was successfully completed in all patients, using 46 pedicle flaps and 27 free tissue transfers. There were no flap losses or cardiopulmonary complications. Overall, the complication rate was 26 percent (29 percent for pedicle TRAM and 22 percent for free TRAM flaps). The median follow-up period among the 53 patients was 22.6 months (range of three to 48 months). All patients employed preoperatively resumed their occupations postoperatively. CONCLUSIONS: Our experience indicates that immediate TRAM breast reconstruction is a safe and viable option for patients seeking reconstruction at the time of mastectomy.

Adult↗
PubMed1995

Effect of sublethal liver injury on doxorubicin metabolism.

Centrilobular hepatocyte contribution to doxorubicin (DOX) metabolism and myelotoxicity was probed with bromobenzene (BRB), a known centrilobular hepatotoxin. New Zealand White rabbits were given DOX, 3 mg/kg i.v. After 4 weeks, the rabbits were pretreated i. p. with 2.6 ml/kg 40% solution of BRB in corn oil followed 72 h later with a 3-mg/kg dose of DOX. Pharmacokinetics of DOX after BRB pretreatment was mildly changed from control. Significantly increased plasma concentrations of doxorubicinol and its aglycone product, 7-deoxydoxorubicinol aglycone, were detected. Treatment with BRB alone was not lethal; however, in three of seven rabbits, the combination of DOX and BRB was. The mortality appeared to be related to myelosuppression. We conclude that toxin-induced hepato-cellular necrosis causes increased DOX-induced myelotoxicity. Following BRB pretreatment, the relatively small pharmacokinetic changes of parent compound concentrations as compared with greater changes in plasma pharmacokinetics of its alcohol metabolites suggest systemic changes in drug metabolism and distribution in the setting of hepatic disease may be the cause of increased toxicity.

Animals↗
PubMed1994

Hepatic artery infusion of doxorubicin with hepatic venous drug extraction.

Hepatic artery infusion (HAI) has been used to take advantage of the steep dose-response relationship characteristic of chemotherapeutic agents. Systemic toxicity, however, remains the dose limiting factor for HAI of low hepatic extraction drugs. This investigation compared the pharmacokinetics of doxorubicin administered using a system that combines HAI and hepatic venous drug extraction (HVDE) versus systemic administration without HVDE. HAI was accomplished by transfemoral cannulation of the hepatic artery. HVDE was aided by use of a double-balloon catheter inserted fluoroscopically via femoral vein cutdown into the inferior vena cava. Inflation of the balloons above and below the hepatic veins allowed collection of hepatic venous effluent. Hepatic venous blood was pumped through the double-balloon catheter into an extracorporeal circuit with activated carbon filters to extract drug prior to return to the systemic circulation. Domestic female swine (25-35 kg) received 3 mg/kg doxorubicin over 90 min via HAI. HVDE was performed for 240 min following initiation of HAI (Time 0-240 min). Control swine underwent hepatic venous isolation using the double-balloon catheter without drug filtration and received 3 mg/kg doxorubicin over 90 min via systemic vein (SYSI). Serum and myocardial doxorubicin and doxorubicinol levels were assayed using HPLC. Blood was serially sampled from hepatic vein blood, from the extracorporeal circuit after filtration, and from a systemic artery. Area under the curve (AUC) was integrated from time-concentration plots over Time 0-180 min.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Hepatoma registry of the Western world. Repeat Hepatic Resection Registry.

The western HCC registry comprised data from 322 patients who underwent hepatic resection for HCC over a 50-year period. The majority of patients had lesions > 4 cm and were symptomatic at presentation. Lesions were mostly unicentric. Cirrhosis was not a prevalent problem, unlike the East. In the most recent decade, 1980-1989, we noted a significant decrease in operative mortality from 19% to 10% overall, and 15% to 4% in the noncirrhotic group. We identified four variables that resulted in poorer postresectional outcome: cirrhosis, regional nodal disease, multicentric disease, and tumor-free resectional margin < 1 cm. Although these factors are associated with a poorer outcome after resection, whether they should serve as contraindications to surgery should be determined by individual surgeons, taking into account the patient's overall status, concomitant risk factors, and treatment objectives.

Adolescent↗
PubMed1994

Age-related differences in breast cancer treatment.

BACKGROUND: More than half of the cases of breast cancer treated in the United States occur in women over age 65. This study investigates age-related differences in breast cancer therapy. METHODS: A retrospective review of all women with primary operable invasive breast cancer treated at the University of Michigan Breast Care Center over a 30-month period showed a total of 77 older patients aged > or = 65 years (median, 71; oldest patient, 92) for whom full information was available regarding comorbidity, tumor stage and histology, and details of surgery, radiation, and chemohormonal therapy and complications. Fifty-one similar younger patients aged 55-64 years (median, 59) were identified for comparison. Patients were classified as either having received standard treatment or non-standard treatment. Standard therapy was prospectively defined as follows: local/regional--lumpectomy and axillary lymph node dissection plus radiation therapy or modified radical mastectomy; systemic--chemotherapy and/or tamoxifen for stage II disease. A comorbidity score calculated for each patient assigned one point each for nursing home residence, nonambulatory status, recent surgery, and each medical problem requiring drug therapy. RESULTS: When overall treatment (local/regional plus systemic) was assessed, proportionately fewer older patients (55 of 77 versus 47 of 51; p < 0.01) received standard treatment. Fewer older than younger patients (62 of 77 versus 50 of 51; p < 0.01) received surgical therapy that included an axillary dissection. A smaller proportion of older patients received radiation therapy following lumpectomy and axillary lymph node dissection (26 of 29 versus 19 of 19; N.S.). Overall, only 59 of 77 older patients versus 50 of 51 younger patients (p < 0.001) received standard local/regional care. Similar proportions of younger and older patients (19 of 22 and 24 of 30, respectively) received standard systemic therapy for stage II breast cancer, but older patients were less likely to receive chemotherapy than younger patients (7% versus 50%; p < 0.001). Treatment-related complications were not age-related but were more frequent in patients receiving standard treatment than in patients receiving nonstandard treatment (45 of 102 versus two of 26; p < 0.001). Comorbidity score correlated with the use of nonstandard therapy but not with age. The scores for both older and younger patients receiving overall standard treatment were 0.8 versus 1.5 and 1.4, respectively, in patients receiving nonstandard treatment. Interestingly, explanations for decisions to deviate from standard treatment guidelines were often not identified. Comorbidity was explicitly noted in only one of four younger patients who received nonstandard treatment therapy. In 22 older patients who received nonstandard treatment, comorbidity was cited in eight cases, patient age was cited in six cases, and patient choice was cited in four cases. Follow-up (median, 34 months) did not show that disease-free or overall survival differences were related to age or to treatment (standard versus nonstandard). CONCLUSIONS: These data demonstrate age-related variations in breast cancer treatment in a multidisciplinary breast care unit. Lower complication rates and equivalent short-term outcomes in women who received nonstandard therapy suggest good clinical judgment may have played a role in these differences. Although age-related patient preferences and comorbidity are relevant, the age-related attitudes of caregivers must also be taken into account to fully explain these variations.

Age Factors↗
PubMed1994

Breast cancer in the elderly patient: early detection with mammography.

PURPOSE: To determine the mammographic features and differences in stage of breast carcinomas in elderly women with malignancies detected with palpation or mammography at presentation. MATERIALS AND METHODS: The mammograms and clinical records of 60 patients (aged 75 years or older) with 62 breast carcinomas, detected during 40 consecutive months, were retrospectively reviewed. A variety of dedicated devices and processing equipment were used. The histologic features, mammographic appearance, mode of detection, and stage of disease were determined. Statistically significant differences between subgroups were calculated with the Student t and chi 2 tests. RESULTS: Sixty cancers (97%) were seen on mammograms. Seventeen tumors detected with annual mammography differed significantly from the 45 carcinomas in nonscreened patients in diameter (1.1 vs 2.1 cm; P < .0005) and stage (14 minimal [82%] of 17 tumors vs 15 minimal [33%] of 45 tumors; P < .0005). Thirty-five nonpalpable malignancies differed significantly from 27 palpable masses in diameter (1.2 vs 2.3 cm; P = .01) and stage (25 tumors minimal [71%] vs four tumors minimal [15%]; P < .0005). CONCLUSION: Screening mammography enabled detection of statistically significantly smaller and earlier-stage tumors, most of which were minimal disease.

Age Factors↗
PubMed1994

Breast reconstruction in older women.

BACKGROUND: More than 50% of breast cancer care in the United States occurs in women over age 65 years. This study investigates age-related differences in breast reconstruction practices after mastectomy for breast cancer. METHODS: Retrospective review of University of Michigan Breast Care Center patients revealed 242 female patients with breast cancer who underwent postmastectomy breast reconstruction from 1980 through 1991. Data were complied concerning patient age, reconstruction interval (immediate or delayed), type of breast reconstruction performed, reconstruction-associated complications, and the number of postreconstruction procedures required to obtain the final result. Statistical comparisons were made with the chi-squared test. RESULTS: There were 224 patients aged less than 60 years (range 27 to 59 years; median, 44 years) and 18 patients aged 60 years or more (oldest, 68 years). Of the 18 older patients, three underwent delayed transverse rectus abdominus muscle (TRAM) reconstruction; one received a delayed latissimus dorsi flap placed over a silicone gel prosthesis, and 14 underwent 18 reconstructions (4 bilateral) with silicone gel implants (6 immediate, 12 delayed). The younger patients underwent 269 breast reconstructions (45 bilateral), including 92 autogenous tissue reconstructions (34 immediate TRAM, 58 delayed TRAM), 60 immediate and 88 delayed insertions of an expander or prosthesis, and 29 latissimus dorsi flaps with implant reconstructions (3 immediate, 26 delayed). Seven complications (32%) occurred in the 22 breast reconstructions performed in older women, including capsular contracture surrounding an implant (six patients) and a ventral hernia in one patient with a TRAM flap. Complications occurred in 134 breast reconstructions (50%) performed in younger women. All were related to the reconstruction. In the older women a mean of 1.7 +/- 0.7 operations was required to achieve a final reconstruction result versus 2.1 +/- 1.1 in the younger women (not significant). More operations were required in younger women undergoing prosthetic reconstruction than in older women, but this difference was not statistically significant (2.4 +/- 1.2 versus 1.9 +/- 0.7; p = 0.07). Autogenous tissue reconstruction was performed less frequently in older women (14% versus 34%; p < 0.05). No age-related difference was noted in the rate of immediate (versus delayed) reconstruction (27% versus 36%, respectively). Complications occurred more frequently in women who underwent prosthetic breast reconstruction, particularly in younger women (32% in older women and 64% in younger women; p < 0.01). The complication rate for immediate breast reconstruction in older women (all prosthetic) was less than in younger women (17% versus 59%; p < 0.05). For delayed prosthetic reconstructions, complications also occurred less frequently in older than younger women (38% versus 67%; p < 0.05). Between 1988 and 1992, 91 older women and 180 younger women underwent mastectomy for breast cancer; only 7% of older women versus 38% of younger women underwent breast reconstruction (p < 0.001). CONCLUSIONS: Breast reconstruction is a safe option for older women requiring mastectomy. The full array of reconstruction options (autogenous tissue or implants, immediate or delayed) should be considered for use in women of all ages.

Adult↗
PubMed1993

A clinician-driven home care delivery system.

The financial, entrepreneurial, administrative, and legal forces acting within the home care arena make it difficult for clinicians to develop and operate home care initiatives within an academic setting. HomeMed is a clinician-initiated and -directed home care delivery system wholly owned by the University of Michigan. The advantages of a clinician-directed system include: Assurance that clinical and patient-based factors are the primary determinants of strategic and procedural decisions; Responsiveness of the system to clinician needs; Maintenance of an important role for the referring physician in home care; Economical clinical research by facilitation of protocol therapy in ambulatory and home settings; Reduction of lengths of hospital stays through clinician initiatives; Incorporation of outcome analysis and other research programs into the mission of the system; Clinician commitment to success of the system; and Clinician input on revenue use. Potential disadvantages of a clinician-based system include: Entrepreneurial, financial, and legal naivete; Disconnection from institutional administrative and data management resources; and Inadequate clinician interest and commitment. The University of Michigan HomeMed experience demonstrates a model of clinician-initiated and -directed home care delivery that has been innovative, profitable, and clinically excellent, has engendered broad physician, nurse, pharmacist, and social worker enthusiasm, and has supported individual investigator clinical protocols as well as broad outcomes research initiatives. It is concluded that a clinician-initiated and -directed home care program is feasible and effective, and in some settings may be optimal.

Comprehensive Health Care↗
PubMed1993

Selection criteria for breast cancer chemoprevention subjects.

Early phase chemoprevention trials differ from standard therapeutic clinical trials because asymptomatic, healthy people are treated with a potentially toxic intervention for a prolonged period of time. Current subject selection protocols have relied upon epidemiological methods to identify high-risk individuals. Most available data provide risk estimates for various individual risk factors, but few have reported risk estimates for combinations of risk factors. Selection criteria for the large tamoxifen intervention trial (NSABP P1) were developed from the work of Gail et al. [1]. The Gail model takes into account non-genetic factors (e.g., nulliparity, age at menarche, preexisting pathological conditions) and genetic factors (family history). Using a lifetime risk of 10% of developing breast cancer as a standard to intervene, NSABP P1 uses the Gail algorithm to select pre- and postmenopausal women for a primary intervention trial. This approach has been criticized for being insufficiently selective (i.e., all women > or = 60 yrs), but appears to be the best available method to select subjects for a chemoprevention trial. Other approaches have been based on identification of very high-risk women with acknowledged pathologic conditions [lobular carcinoma in situ, ductal carcinoma in situ (DCIS)]. Attempting to use these proliferative lesions as pathologic endpoints for drug effect has not been attempted. DCIS as a risk factor for tamoxifen intervention was excluded because of controversies over its management and because of frequent difficulties in distinguishing microinvasive from non-invasive lesions. Women treated for early stage breast cancer (Stage I) may be subjects for early stage chemopreventive interventions.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1993

Benefits of a multidisciplinary approach to breast care.

The University of Michigan Breast Care Center (BCC) was established in 1985 to provide comprehensive, multidisciplinary diagnosis and treatment of benign and malignant breast disease. This work presents an overview of our experience in the BCC and assesses the clinical, academic, financial, and educational effectiveness of the program. A database was used to generate a list of all patients seen in the BCC between February 1, 1985 and December 31, 1991. Participating departments provided information regarding outpatient, inpatient, clinical and consultative activities, and referral patterns attributable to BCC endeavors. BCC educational and academic activities were reviewed and profiled. Clinical information was culled from the BCC database, hospital records, and the hospital tumor registry. The BCC has resulted in a fivefold increase in breast care related activity at the University of Michigan Medical Center. Over half of the patients treated in the BCC with primary operable breast cancer receive breast-conserving therapy. The BCC performs a unique educational function, providing the primary breast care experience for house staff as well as one third of the third year medical school class. The BCC supports over 20 clinical research protocols, and patient enrollment in clinical trials has increased dramatically since 1985. The BCC also provides support to basic science researchers receiving over 2.5 million dollars in peer reviewed direct cost support. These data suggest that a multidisciplinary approach to patient care as embodied by the BCC can be clinically, financially, and academically superior and productive. This model warrants further investigation not only in the field of breast care, but also in other clinical situations that require multidisciplinary input and therapy.

Breast Diseases↗
PubMed1993

Pulmonary capillary pressure measurement during global hypoxia in sheep.

Analysis of the pressure decay following pulmonary artery occlusion can be used to determine pulmonary capillary pressure and to calculate the magnitudes of the arterial and venous components of pulmonary vascular resistance. The separation of pulmonary vascular resistance into components has been termed "the longitudinal distribution of pulmonary vascular resistance" to emphasize the fact that different pressures occur at a number of sites in the pulmonary circulation. The longitudinal distribution of pulmonary vascular resistance is closely related to pulmonary capillary pressure. Several methods of data analysis have been proposed to determine pulmonary capillary pressure from the pressure decay following pulmonary artery occlusion. In this study, three methods of data analysis were applied to the model of hypoxic pulmonary vasoconstriction to evaluate the validity of the methodology in a well known model. Pulmonary artery occlusion pressure decay curves were obtained from eight halothane-anesthetized sheep during control conditions (FIO2 = 0.99) and during hypoxic ventilation (FIO2 = 0.14). Analysis of the pulmonary artery occlusion pressure decay curves indicated the following results: 1) Hypoxia increased mean pulmonary artery pressure by 105% and increased pulmonary vascular resistance by 149%; 2) the increase in the calculated arterial component of pulmonary vascular resistance accounted for 88% of the increase in pulmonary vascular resistance with hypoxia; and 3) hypoxia produced only a 1.0 mm Hg increase in pulmonary capillary pressure. These results are consistent with other evidence showing that hypoxia primarily produces precapillary pulmonary vasoconstriction and has little effect on pulmonary capillary pressure. Pulmonary artery occlusion pressure decay curve analysis appears to be a valid technique for the measurement of pulmonary capillary pressure during hypoxia in intact anesthetized animals.

Animals↗
PubMed1993

Immediate, bilateral transverse rectus abdominis musculocutaneous (TRAM) flap reconstruction after mastectomy.

Although breast reconstruction has been shown to provide psychological benefits in mastectomy patients, there is reluctance to perform immediate, bilateral TRAM flap reconstruction because of concerns regarding magnitude of the procedure, length of hospitalization, potential complications, and long-term recovery. Between June, 1990 and March 1992, 15 patients underwent immediate, bilateral TRAM flap reconstruction following bilateral mastectomy at the University of Michigan Hospitals. Diagnoses included lobular carcinoma in situ (nine patients), strong family history of breast cancer (five), or bilateral breast cancer (one). Invasive breast cancer was present in three patients. Three modified radical mastectomies and 27 simple mastectomies were performed. Bilateral pedicle TRAM flap reconstruction was carried out at the same time in all patients (30 flaps total). Marginal loss occurred in one flap (3%). Additional complications included marginal necrosis of the abdominal donor site wound (one), wound infection (two), and abdominal donor site hernia (one). Median hospital stay was 7 days. Median follow-up was 13 months (range 4-25 months). All patients have resumed their accustomed pre-operative activity patterns. These findings demonstrate that immediate, bilateral TRAM flap reconstruction is a safe and effective option for breast reconstruction after mastectomy.

Abdominal Muscles↗
PubMed1993

Parathyroid carcinoma: the relationship of nuclear DNA content to clinical outcome.

This article reports the use of flow cytometry to determine tumor nuclear DNA content and its correlations with clinical outcome in a series of patients with parathyroid carcinoma. Information concerning nine patients with parathyroid cancer (aged 25 to 88 years) was reviewed. Paraffin-embedded, formalin-fixed archival tissue was used to determine tumor DNA content flow cytometrically. Twenty-five operative procedures were performed in nine patients, including 11 parathyroidectomies, two wide local excisions, six central neck dissections, and four median sternotomies for resection of metastases. With flow cytometry used to determine a tumor DNA index, five patients had evidence of tumor aneuploidy; in two patients two aneuploid peaks were evident. The DNA index ranged from 0.7 (hypodiploid) to 1.92 (mean, 1.31). Follow-up ranged from 1 to 18 years. Four patients died. Five were alive 1 to 13 years after diagnosis of parathyroid disease. Four of the five patients with evidence of tumor aneuploidy had metastatic disease and died, and the fifth has had three local recurrences. The four patients with diploid tumors were alive and free of disease 1, 3, 4, and 8 years after the initial operation. It is concluded that in patients with clinically or pathologically demonstrated parathyroid cancer, flow cytometry may help differentiate those whose cancers are likely to behave indolently (diploid tumors) from those with tumors (aneuploid) more likely to behave aggressively by recurring locally or metastasizing.

Adult↗
PubMed1990

Clostridial infection of a locally recurrent renal cell carcinoma with sepsis.

An association between clostridial sepsis and malignancy is well established in the literature. Although anaerobes are a relatively infrequent cause of renal abscess, there have been recent reports of anaerobic abscesses occurring in renal tumor masses. The present report describes a case of sepsis due to Clostridium perfringens infection of a locally recurrent renal cell carcinoma. The infection may have originated either from tumor invasion of the adjacent bowel or by hematogenous seeding of the mass at the time of colonoscopy. Patients with bulky, necrotic tumors who have invasive diagnostic procedures relating to either the gastrointestinal or urogenital tracts, as well as those having malignancies involving these systems, are at increased risk of infection with bowel anaerobes. Clostridial abscesses with accompanying sepsis occur in this setting, and empiric antibiotic regimens should include coverage for these organisms. Early, aggressive surgical intervention is essential.

Carcinoma, Renal Cell↗
PubMed1985

Lymphatic dissemination of hepatic metastases. Implications for the follow-up and treatment of patients with colorectal cancer.

Hepatic spread of colorectal cancer is a prominent cause of treatment failure, but selected patients with liver metastases may attain long-term palliation or cure with liver resection. A review of the records of 81 patients seen at the National Cancer Institute for treatment of colorectal hepatic metastases revealed 7 instances of metastases discovered at operation within the hepatic lymphatic drainage in the absence of other extrahepatic tumor. These patients were studied with reference to location and stage of the primary colon cancer and location of metastases at the time of planned liver resection. All seven patients had their extrahepatic lymphatic disease limited to nodes draining the liver, implicating lymphatic dissemination from hepatic metastases as the mechanism of tumor spread. This pattern of spread rendered these patients unresectable for cure. If lymphatic metastases occur from hepatic tumor this implies a need for frequent and thorough follow-up of patients following resection of a primary colon cancer, and indicates urgency in treatment of liver metastases.

Colonic Neoplasms↗
PubMed1985

Hepatic resection of colorectal metastases. Influence of clinical factors and adjuvant intraperitoneal 5-fluorouracil via Tenckhoff catheter on survival.

This report analyzes an experience with 33 hepatic resections for metastatic colorectal cancer over a 7-year period and with intraperitoneal 5-FU administered as a postresection adjuvant in 21 of these patients. Particular emphasis is placed on the identification of clinical determinants of postresection survival. There was no operative mortality in this series. Postoperative complications occurred in 27% of patients, and the incidence of complications correlated with intraoperative blood loss (p = 0.002). Two- and 4-year estimated survivals were 72% and 53%, respectively. Patients with three or fewer metastases resected or with unilobar disease had improved survival when compared with patients having more than three metastases or bilobar disease, respectively (p less than 0.05). Disease-free survival was improved in patients with microscopically negative resection margins (p = 0.019). Dukes' stage of the primary lesion, interval between bowel resection and detection of hepatic metastases, method of detection of metastases, preoperative CEA level, and type of operation performed were not predictive of postresection survival. Intraperitoneal 5-FU was well tolerated. There was a trend toward improved survival in patients receiving adjuvant chemotherapy, but this was not statistically significant. It is concluded that the number of metastases resected, the distribution of the metastases, and the technical adequacy of the excision are all predictive of outcome following hepatic resection of colorectal metastases. Encouraging results with the use of intraperitoneal 5-FU as a postresection adjuvant have led to the initiation of a prospective randomized trial investigating this modality at the NCI.

Adenocarcinoma↗