Chemosensitivity patterns and expression of human multidrug resistance-associated MDR1 gene by human gastric and colorectal carcinoma cell lines.

We compared the in vitro sensitivity patterns to cytotoxic drugs and expression of the multidrug resistance-associated MDR1 gene (also known as PGY1 gene) in four gastric carcinoma cell lines with those obtained in a panel of 11 colorectal carcinoma cell lines. In addition, we tested the effects of leucovorin on enhancement of fluorinated pyrimidine-induced cytotoxicity. We used a semiautomated tetrazolium dye assay [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (tetrazolyl blue)] (MTT) to compare the drug sensitivity of the gastric carcinoma cell lines with that of the colorectal carcinoma cell lines. The gastric carcinoma cell lines were more sensitive to some drugs, including doxorubicin and cisplatin, but not to the fluorinated pyrimidines. Addition of leucovorin at a clinically achievable concentration enhanced the cytotoxic effects of both fluorouracil and floxuridine in colorectal carcinoma cell lines, but it enhanced the effects of only floxuridine in gastric carcinoma cell lines. With the use of a slot blot assay, relatively low levels of MDR1 RNA were present in all four gastric carcinoma cell lines, while intermediate or high levels were present in most of the colorectal carcinoma cell lines. In general, our findings reflect clinical experience and may help in the design of clinical trials.

Expression of a multidrug resistance gene in human cancers.

Many cancers have been cured by chemotherapeutic agents. However, other cancers are intrinsically drug resistant, and some acquire resistance following chemotherapy. Cloning of the cDNA for the human MDR1 gene (also known as PGY1), which encodes the multidrug efflux protein P-glycoprotein, has made it possible to measure levels of MDR1 RNA in human cancers. We report the levels of MDR1 RNA in greater than 400 human cancers. MDR1 RNA levels were usually elevated in untreated, intrinsically drug-resistant tumors, including those derived from the colon, kidney, adrenal gland, liver, and pancreas, as well as in carcinoid tumors, chronic myelogenous leukemia in blast crisis, and cell lines of non-small cell carcinoma of the lung (NSCLC) with neuroendocrine properties. MDR1 RNA levels were occasionally elevated in other untreated cancers, including neuroblastoma, acute lymphocytic leukemia (ALL) in adults, acute nonlymphocytic leukemia (ANLL) in adults, and indolent non-Hodgkin's lymphoma. MDR1 RNA levels were also increased in some cancers at relapse after chemotherapy, including ALL, ANLL, breast cancer, neuroblastoma, pheochromocytoma, and nodular, poorly differentiated lymphoma. Many types of drug-sensitive and drug-resistant tumors, including NSCLC and melanoma, contained undetectable or low levels of MDR1 RNA. The consistent association of MDR1 expression with several intrinsically resistant cancers and the increased expression of the MDR1 gene in certain cancers with acquired drug resistance indicate that the MDR1 gene contributes to multidrug resistance in many human cancers. Thus, evaluation of MDR1 gene expression may prove to be a valuable tool in the identification of individuals whose cancers are resistant to specific agents. The information may be useful in designing or altering chemotherapeutic protocols in these patients.

MDR1 gene expression in lung cancer.

The MDR1 gene (also known as PGY1) is frequently overexpressed in multidrug-resistant cell lines. We investigated the role of MDR1 gene expression in lung cancer by performing RNA slot blot analysis in samples from a panel of 24 lung cancers, 10 corresponding nontumorous lung tissues, and 67 tumor cell lines of several histologic types. Almost all of the tumors, nontumorous lung tissues, and cell lines expressed low levels of MDR1 RNA. Relatively higher levels were found in only one type of lung cancer, a subgroup of non-small cell lung cancers expressing neuroendocrine markers. No evidence of MDR1 gene amplification or rearrangements was detected. We found no correlation between MDR1 gene expression in cell lines and (a) in vitro chemosensitivity of the cells, (b) prior therapy status of the patients, or (c) clinical response to therapy. We conclude that the clinical multidrug resistance of many lung cancers cannot be explained solely on the basis of expression of the MDR1 gene.

Expression of cathepsin L in human tumors.

It has been proposed that proteases secreted by cancer cells facilitate tumor invasion and metastasis by degrading the components of extracellular membranes. The lysosomal cysteine protease cathepsin L is synthesized in large amounts and secreted by many malignantly transformed cells in culture. The secreted protease is potent in degrading collagen, laminin, elastin, and other structural proteins of basement membranes. To determine whether human cancers synthesize cathepsin L, the expression of cathepsin L in approximately 100 human tumor samples was determined by quantitative RNA slot blot analysis using a specific human cathepsin L complementary DNA probe. Results of the present study suggest that cancers in general express higher levels of cathepsin L than do normal tissues. Kidney and testicular tumors expressed the highest levels of cathepsin L; non-small cell carcinomas of the lung expressed the next highest levels; and most cancers of the breast, ovary, colon, adrenal, bladder, prostate, and thyroid expressed elevated levels as well. Cathepsin L may prove useful as a diagnostic or prognostic marker of human malignancy.

Expression of a human multidrug resistance gene in ovarian carcinomas.

Expression of the human MDR1 gene has been shown to confer the multidrug resistance (MDR) phenotype to sensitive cells. To investigate the possible contribution of the MDR phenotype to chemoresistance in ovarian carcinoma, we have analyzed MDR1 gene expression in fresh carcinoma specimens from 50 patients. Fifteen received chemotherapy before surgery and were judged as poor responders. Thirty-five patients did not receive any drug before surgery. Control tissues were lymphocytes from 7 patients. Total RNAs were analyzed by Northern and slot blot hybridization techniques using human MDR1 complementary DNA and human gamma-actin complementary DNA probes sequentially as qualitative and quantitative controls. MDR1 transcripts (4.5 kilobases) were observed in the RNA preparations obtained from 3 of 10 patients who were treated with doxorubicin or vincristine, 2 drugs known to select the MDR phenotype in vitro. In 40 other RNA preparations obtained from 35 untreated patients and 5 patients treated exclusively with cyclophosphamide and cis-platinum, no transcript could be detected. Using the exact Fisher test, the difference between the 2 groups was found to be significant (P less than 0.01). The three tumors with elevated MDR1 expression did not show MDR1 DNA amplification. Our study suggests that, in spite of the weak occurrence of the MDR process in patients with ovarian cancers, MDR1 expression can be related to previous treatment with doxorubicin or vincristine. These results favor the expression of the MDR1 gene as one of the determinants involved in the acquired chemoresistance of ovarian cancers.

Phase II trial of biweekly paclitaxel and cisplatin in advanced breast carcinoma: an Eastern Cooperative Oncology Group study.

PURPOSE: To determine the efficacy of a biweekly paclitaxel and cisplatin regimen in patients with advanced breast carcinoma, which has previously been reported to produce an 85% response rate in such patients. PATIENTS AND METHODS: Sixteen patients with metastatic breast carcinoma who had relapsed after prior doxorubicin-containing adjuvant chemotherapy were treated with paclitaxel (90 mg/m2) by intravenous (i.v.) infusion over 3 hours followed by cisplatin (60 mg/m2) given by i.v. infusion over 1 hour on an outpatient basis. Treatment was repeated every 2 weeks if the absolute neutrophil count was > or = 750/microL and platelet count > or = 75,000/microL. After a maximum of eight cycles of paclitaxel/cisplatin, patients received biweekly paclitaxel alone (90 mg/m2 with dose escalation). Thirteen patients were assessable for response and all for toxicity. Nine of 13 patients assessable for response (69%) had at least three sites of metastases and 10 patients (77%) had visceral-dominant disease. RESULTS: Partial response occurred in three of 13 assessable patients (23%; 90% confidence interval, 7% to 49%). All responders had two or fewer sites of metastases. The median time to progression was 4.3 months and the median survival duration was 11.4 months. Patients received a median of seven cycles of therapy (range, two to 21). Severe and/or life-threatening toxicity occurred in 50% and 38%, respectively, and consisted primarily of granulocytopenia, anemia, and neuropathy. The trial was terminated after the first interim analysis as per its two-stage design, since it was unlikely that the response rate would exceed 70%. CONCLUSION: Biweekly paclitaxel/cisplatin is not likely to produce a response rate greater than 70% in patients with metastatic breast cancer who have relapsed after prior doxorubicin-containing adjuvant chemotherapy and who have multiple sites of metastases and/or visceral-dominant disease.

Expression of the multidrug resistance, MDR1, gene in neuroblastomas.

Metastatic neuroblastoma is a childhood malignancy that is frequently responsive to chemotherapy with doxorubicin, vincristine, and teniposide (VM26), among other drugs, but in the majority of treated patients, the tumor recurs during or after chemotherapy. In this work, we have examined the hypothesis that the development of resistance to chemotherapy in neuroblastoma might be related to the expression of the human MDR1 gene, which encodes a multidrug transporter that functions as an energy-dependent drug efflux pump. RNA samples from 49 neuroblastomas were analyzed, including 31 from untreated and 18 from treated patients. MDR1 RNA was detectable in the majority of treated and untreated tumors using a sensitive, semiquantitative slot blot assay. Of the samples from treated patients, five of 18 were found to have high MDR1 RNA levels, whereas only three of 31 from untreated patients had high MDR1 levels, a statistically significant difference (P less than .01). These results show that high levels of MDR1 RNA are often associated with resistance to chemotherapy in neuroblastoma and suggest that they may contribute to this resistance. Many of the neuroblastoma samples were also evaluated for N-myc amplification but there was no correlation between N-myc copy number and the level of MDR1 mRNA expression.

A pilot study of interferon alfa-2a in combination with fluorouracil plus high-dose leucovorin in metastatic gastrointestinal carcinoma.

Thirty-one assessable patients with metastatic adenocarcinoma of the gastrointestinal tract were entered onto a pilot study designed to assess the impact of recombinant interferon alpha-2a (rIFN alpha-2a) on the toxicity and pharmacokinetics of fluorouracil (5-FU) and leucovorin (LV). Patients received an initial cycle of 5-FU (370 or 425 mg/m2/d) with LV (500 mg/m2/d) for 5 days. If tolerated, the patient received the same dose of 5-FU/LV for the second cycle on days 2 to 6, with rIFN alpha-2a at 5 x 10(6) or 10 x 10(6) U/m2/d on days 1 to 7, or with 3 x 10(6) U/m2/d on days 1 to 14. In 26 matched cycles, rIFN alpha-2a administration was associated with an increased incidence of dose-limiting mucositis and diarrhea and a significantly lower median platelet nadir; rIFN alpha-2a did not significantly affect the median WBC or granulocyte nadir. Dose-limiting toxicity occurred in all six patients entered at 425 mg/m2/d of 5-FU/LV within two cycles. The majority of patients treated with 370 mg/m2/d of 5-FU/LV and 10 x 10(6) U/m2/d rIFN alpha-2a experienced grade 3 to 4 mucositis and diarrhea, whereas patients receiving 3 x 10(6) and 5 x 10(6) U/m2/d rIFN alpha-2a had acceptable toxicity. Administration of rIFN alpha-2a was associated with a dose-dependent decrease in 5-FU clearance. The increase in the area under the 5-FU concentration-time curve (AUC) was 1.3-fold and 1.5-fold in patients receiving 5 x 10(6) and 10 x 10(6) U/m2/d rIFN alpha-2a, respectively. Thus, the increase in 5-FU toxicity with rIFN alpha-2a may be explained by alterations in 5-FU pharmacokinetics. In 22 patients without prior 5-FU therapy, three complete (13.6%) and seven partial (31.8%) responses were seen, for an overall response rate of 45.4% (95% confidence interval, 24.4% to 67.8%). Since the 5 x 10(6) U/m2/d dose of rIFN alpha-2a increased the 5-FU drug exposure and was associated with acceptable toxicity, we recommend its further evaluation as given on days 1 to 7 in combination with 5-FU 370 mg/m2/d, with high-dose LV given on days 2 to 6.

Docetaxel combined with trastuzumab is an active regimen in HER-2 3+ overexpressing and fluorescent in situ hybridization-positive metastatic breast cancer: a multi-institutional phase II trial.

PURPOSE: To determine the efficacy and safety of weekly docetaxel and trastuzumab as first- or second-line therapy in women with HER-2-overexpressing metastatic breast cancer and to correlate the efficacy of trastuzumab with HER-2 status as determined by immunohistochemistry assay and fluorescent in situ hybridization (FISH). PATIENTS AND METHODS: Twenty-six women with HER-2-positive (HercepTest [Dako Corp, Carpenteria, CA]2 to 3+) metastatic breast cancer were enrolled onto this study of trastuzumab (4 mg/kg load; 2 mg/kg/wk administered intravenously) and docetaxel (35 mg/m2/wk for 6 weeks). RESULTS: Using an intent-to-treat analysis, the overall response rate was 50% (13 of 26 patients). Eight patients (31%) had a period of stable disease posttherapy. Among HER-2 3+ patients, the overall response rate was 63% (12 of 19 patients) compared with a 14% response rate (one of seven patients) for HER-2 2+ patients (P=.07). Patients with FISH-positive tumors experienced an overall response rate of 64%. Median time to progression was 12.4 months for the entire cohort (HER-2 3+ tumors, 12.3 months; HER-2 2+ lesions, 9.5 months) and median survival was 22.1 months. All HER-2 3+ patients were FISH-positive; the only HER-2 2+ patient responding to treatment was also FISH-positive. Grade 4 toxicities occurred in four patients; most toxicities were mild. CONCLUSION: Trastuzumab plus docetaxel is an active and well-tolerated regimen in women with HER-2 3+ overexpressing or FISH-positive metastatic breast cancer.

Quantitative reverse transcriptase-polymerase chain reaction measured expression of MDR1 and MRP in primary breast carcinoma.

To evaluate the clinical significance of drug resistance mechanisms in breast cancer, we examined the expression of MDR1 and MRP in primary breast carcinoma and normal adjacent tissue using a highly quantitative and reproducible reverse transcription-PCR assay. Expression of both genes was observed in all specimens examined, both tumor (n = 74) and normal adjacent tissue (n = 55). The expression of MDR1, however, was low, with the level of expression being 25 times less than the drug-resistant control cell line KB 8-5. Immunohistochemical analysis of P-glycoprotein corroborated the PCR results; only 6% (2 of 31) were positive for JSB1 staining, and 0 of 32 were positive for for UIC2. MRP expression did not exceed control cell line levels, and immunohistochemistry detected moderate levels of expression. MDR1 expression was independent of grade, stage, tumor size, nodal status, metastasis, and estrogen receptor and progesterone receptor status. There was, however, a significant correlation of MDR1 expression with age and histology. Approximately twice the expression of MDR1 was observed in the < 50 age group compared to the > 50 age group, and lobular carcinoma had 4 times the expression of MDR1 of other histological types. MRP expression was independent of all other clinical parameters. Thus, these results show that although MDR1 expression is detectable in primary breast carcinoma by PCR, this expression as measured by quantitative reverse transcriptase-PCR is extremely low. The significance of these low levels is yet to be determined. MDR1 expression was higher in < 50 age group and lobular carcinoma, which may contribute to poor prognosis associated with young age and lobular histology.

An automated tube-type blood viscometer: validation studies.

The technical complexity of previous rheometers has tended to limit the availability of blood viscosity data obtained over a wide range of shear rates. However, an automated tube-type viscometer, the Rheolog, has been developed; it employs a disposable flow assembly and less than five minutes are required to obtain blood viscosity results over a shear rate range of 1-1500 s(-1). We have carried out validation studies of the Rheolog using normal human blood and have compared these results with those obtained by cone-plate and Couette viscometers; storage time and temperature effects were also evaluated. Replicate measurements indicated mean CV levels less than 5%, and were independent of hematocrit and shear rate. Rheolog blood viscosity data agreed closely with those from other viscometers: average Rheolog differences from mean cone-plate and Couette values were -0.3% at 28% hematocrit, -1.4% at 41% hematocrit (i.e., native), and 1.0% at 56% hematocrit. Storage at room temperature up to 8 hours and at 4 degrees C up to 4 days had minimal effects whereas notable changes were observed when stored for 3 hours at 37 degrees C. Our results indicate that, within the hematocrit and shear rate limits employed herein, the Rheolog provides rapid, accurate and reproducible blood viscosity data, and suggest its usefulness for both basic science and clinical studies.

Eastern Cooperative Oncology Group studies of paclitaxel and doxorubicin in advanced breast cancer.

Based on their single-agent activity in metastatic breast cancer, paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) and doxorubicin have been alternated and combined in Eastern Cooperative Oncology Group studies to identify a tolerable dose and schedule. A pilot trial in patients who had received no more than one prior chemotherapy regimen alternated paclitaxel 200 mg/m2 and doxorubicin 75 mg/m2 every 3 weeks. Seven of 12 patients had objective (complete plus partial) responses. A second (phase I) trial combined doxorubicin as an intravenous push and paclitaxel as a 24-hour continuous infusion. To evaluate the effect of the schedule on toxicity, the drug administration sequence (doxorubicin-->paclitaxel or paclitaxel-->doxorubicin) was alternated both between and within patients. initial doses were paclitaxel 150 mg/m2 and doxorubicin 50 mg/m2 in six patients, with a subsequent six patients receiving 175 and 60 mg/m2, respectively. Dose-limiting mucositis was seen at the second dose level when paclitaxel preceded doxorubicin, suggesting an important role for the administration sequence in determining toxicity (and possibly efficacy) in this regimen. These results support the sequence of doxorubicin 50 mg/m2 followed by paclitaxel 150 mg/m2 as the maximum tolerated dose. This combination has been incorporated as a treatment arm in an ongoing randomized prospective phase III Intergroup trial. By comparing the combination with both drugs as single agents (with crossover to the opposite agent at disease progression), investigators will attempt to assess response, toxicity, and time to progression as well as the degree of cross-resistance between the two agents. Given the poor prognosis of patients with advanced breast cancer, the three arms also will be evaluated in terms of patients' quality of life.

Paclitaxel (Taxol)/doxorubicin combinations in advanced breast cancer: the Eastern Cooperative Oncology Group experience.

Paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ), the first taxane to enter routine clinical practice, has aroused considerable interest due to its novel mechanism of action and its significant activity in metastatic breast cancer. Given this activity, it seemed logical to attempt to combine paclitaxel with doxorubicin, the other most active single agent in metastatic breast cancer. The Eastern Cooperative Oncology Group performed two trials investigating paclitaxel/doxorubicin combinations in patients with advanced breast cancer in an attempt to identify a tolerable dose and schedule of the combination. In the first trial, paclitaxel and doxorubicin were alternated every 3 weeks in doses of 200 mg/m2 and 75 mg/m2, respectively, for patients who had received no more than one prior chemotherapeutic regimen. Therapy was well tolerated in this setting. At these doses, paclitaxel induced more granulocytopenia and less thrombocytopenia than did doxorubicin. Objective responses (complete and partial responses) were seen in seven of 12 patients; two other patients had improved disease (relief of pain in bony metastases). A second limited-institution Eastern Cooperative Oncology Group trial evaluated paclitaxel and doxorubicin given in combination. In this phase I trial, doxorubicin was given as an intravenous push and paclitaxel as a 24-hour continuous infusion. The sequence of drug administration (D-->P or P-->D) was alternated both between and within patients, so that we might evaluate the effect of administration schedule on toxicity. Therapy was begun at an initial paclitaxel dose of 150 mg/m2 and an initial doxorubicin dose of 50 mg/m2 in six patients, with a subsequent six patients receiving 175 and 60 mg/m2, respectively, of paclitaxel and doxorubicin. In addition, patients received granulocyte colony-stimulating factor 5 micrograms/kg/d. While therapy at the initial dose level was well tolerated, dose-limiting mucositis was seen at the second dose level, although only when paclitaxel preceded doxorubicin. This suggests that sequence of drug administration in paclitaxel-based regimens may play an important role as a determinant of toxicity and (perhaps) efficacy, a finding similar to that seen when paclitaxel and cisplatin were combined in patients with ovarian cancer. Based on this study, we identified the sequence of doxorubicin (50 mg/m2) followed by paclitaxel (150 mg/m2) to be the maximum tolerated dose. This combination is currently being compared with paclitaxel alone and doxorubicin alone in patients with advanced breast cancer in an intergroup trial led by the Eastern Cooperative Oncology Group.

The impact of tamoxifen on breast recurrence, cosmesis, complications, and survival in estrogen receptor-positive early-stage breast cancer.

PURPOSE: To evaluate the impact of tamoxifen on breast recurrence, cosmesis, complications, overall and cause-specific survival in women with Stage I-II breast cancer and estrogen receptor positive tumors undergoing conservative surgery and radiation. METHODS AND MATERIALS: From 1982 to 1991, 491 women with estrogen receptor positive Stage I-II breast cancer underwent excisional biopsy, axillary dissection, and radiation. The median age of patient population was 60 years with 21% < 50 years of age. The median follow-up was 5.3 years (range 0.1 to 12.8). Sixty-nine percent had T1 tumors and 83% had histologically negative axillary nodes. Re-excision was performed in 49% and the final margin of resection was negative in 64%. One hundred fifty-four patients received tamoxifen and 337 patients received no adjuvant therapy. None of the patients received adjuvant chemotherapy. RESULTS: There were no significant differences between the two groups for age, race, clinical tumor size, histology, the use of re-excision, or median total dose to the primary. Patients who received tamoxifen were more often axillary node positive (44% tamoxifen vs. 5% no tamoxifen), and, therefore, a greater percentage received treatment to the breast and regional nodes. The tamoxifen patients less often had unknown margins of resection (9% tamoxifen vs. 22% no tamoxifen). The 5-year actuarial breast recurrence rate was 4% for the tamoxifen patients compared to 7% for patients not receiving tamoxifen (p = 0.21). Tamoxifen resulted in a modest decrease in the 5-year actuarial risk of a breast recurrence in axillary node-negative patients, in those with unknown or close margins of resection, and in those who underwent a single excision. Axillary node-positive patients had a clinically significant decrease in the 5-year actuarial breast recurrence rate (21 vs. 4%; p = 0.08). The 5-year actuarial rate of distant metastasis was not significantly decreased by the addition of adjuvant tamoxifen in all patients or pathologic node-negative patients. Pathologically node-positive patients had a significant decrease in distant metastasis (35 vs. 11%; p = 0.02). There were no significant differences in cause-specific survival for patients receiving tamoxifen when compared to observation (95% no tamoxifen vs. 89% tamoxifen; p = 0.24). Similar findings were noted for pathologically node-negative patients. However, axillary node-positive patients receiving tamoxifen had an improvement in 5-year actuarial cause-specific survival (90% tamoxifen vs. 70% no tamoxifen; p = 0.10). Cosmesis (physician assessment) was good to excellent in 85% of the tamoxifen patients compared to 88% of the patients who did not receive tamoxifen. CONCLUSION: The addition of tamoxifen to conservative surgery and radiation in women with Stage I-II breast cancer and estrogen receptor positive tumors resulted in a modest but not statistically significant decrease in the 5-year actuarial risk of a breast recurrence. Tamoxifen significantly decreased the 5-year actuarial risk of distant metastasis in axillary node-positive patients and there was a trend towards improvement in cause-specific survival that was not statistically significant. Tamoxifen did not decrease the 5-year actuarial rate of distant metastasis in axillary node negative, patients and in this group, there was no improvement in cause-specific survival. Tamoxifen did not have an adverse effect on cosmesis or complications.

The presence of proliferative breast disease with atypia does not significantly influence outcome in early-stage invasive breast cancer treated with conservative surgery and radiation.

PURPOSE: To evaluate the influence of the benign background breast-tissue change of atypical hyperplasia (AH) on outcome in patients with early-stage invasive breast cancer treated with conservative surgery and radiation. MATERIALS AND METHODS: Four hundred and sixty women with Stage I--II breast cancer treated with conservative surgery and radiation from 1982-1994 had pathologic assessment of their background adjacent benign breast tissue. The median follow-up was 5.6 years (range 0.1-15). The median age was 55 years (range 24-88). Of these, 23% had positive axillary nodes; 25% received adjuvant chemotherapy (CMF or CAF) with (9%) or without (17%) tamoxifen. Of the total, 24% received adjuvant tamoxifen alone. The patients were divided into 2 groups: 131 patients with atypical hyperplasia (ductal, 99 patients; lobular, 20 pts; and type not specified, 12 pts), and 329 patients with no proliferative changes or proliferative changes without atypia. RESULT: A statistically significant difference was observed between the 2 groups for method of detection, primary tumor size, presence of lobular carcinoma in situ (LCIS), pathologic nodal status, region(s) treated with radiation, and type of adjuvant therapy. Patients with atypical hyperplasia (AH) had smaller primary tumors (T1 80% vs. 70%) more often detected solely by mammography (51% vs. 36%) with negative axillary nodes (87% vs. 73%) and radiation treatment to the breast only (93% vs. 78%). LCIS was observed in 9% of the patients with AH and 3% of those without AH. Patients with AH more often received tamoxifen alone (32% vs. 21%), rather than chemotherapy (15% vs. 29%). There were no statistically significant differences between the 2 groups for race, age, menopausal status, family history, histology, histologic subtype DCIS when present, the presence or absence of an extensive intraductal component, final margin status, estrogen or progesterone receptor status, use of re-excision, or total radiation dose to the primary. The 5- and 10-year actuarial ipsilateral breast tumor recurrence rates were 2% and 12% for patients with AH and 4% and 8% for those without AH (p=0.44). Younger women or those with a positive family history of breast cancer with AH did not have an increased rate of breast failure when compared to similar patients without AH. There were no significant differences in the 5- and 10-year actuarial rates of distant metastases (AH 5- and 10-year 7% and 7%, no AH 5- and 10-year 8% and 16%,p=0.31), regional node recurrence (AH 1% and 1%, no AH 1% and 1%,p=0.71), contralateral breast cancer (AH 3% and 3%, no AH 3% and 8%,p=0.71), overall survival (AH 95% and 86%, no AH 95% and 89%, p=0.79), or cause-specific survival (AH 98% and 95%, no AH 96% and 91%,p=0.27). Subset analysis for ipsilateral breast tumor recurrence, distant metastases, overall, and cause-specific survival for T1 vs. T2 tumors and path node-negative vs. path node-positive patients revealed no significant differences between the 2 groups. CONCLUSION: AH was not associated with an increased risk of ipsilateral breast tumor recurrence or contralateral breast cancer in this study of patients with invasive breast cancer treated with conservative surgery and radiation. Therefore, the presence of proliferative changes with atypia in background benign breast tissue should not be a contraindication to breast-conservation therapy.

A close or positive margin after mastectomy is not an indication for chest wall irradiation except in women aged fifty or younger.

INTRODUCTION: Indications for postmastectomy radiation include primary tumor size > or = 5 cm and/or > or = 4 positive axillary nodes. In clinical practice, patients with a close or positive margin after mastectomy are also often treated with postmastectomy radiation. However, there is little data regarding the risk of a chest wall recurrence in patients with close or positive margins who otherwise would be considered low risk (tumor size <5 cm and/or 0-3 positive nodes). To address this issue, we assessed the risk of a chest wall recurrence in women with Stage I-II breast cancer who underwent mastectomy and were found to have primary tumor size <5 cm and 0-3 positive nodes with a close or positive deep margin. METHODS AND MATERIALS: The pathologic reports from 789 patients treated by mastectomy between 1985 and 1994 at our institution were retrospectively reviewed. Of these, 136 (17%) had tumor within 1 cm of the deep resection margin. The study population consists of 34 of these patients with close or positive margins whose primary tumor size was <5 cm with 0-3 positive axillary nodes and who received no postoperative radiation. The median age was 43 years (range 29-76). Of these, 44% had T1 tumors and 56% T2 tumors. Pathologic axillary nodal status was negative in 65% and positive in 35%. The median number of positive nodes was 1. The deep margin was positive in 2 patients, < or = 2 mm in 17 patients, 2.1-4 mm in 7 patients and 4.1-6 mm in 8 patients. Of the 34 patients, 67% received adjuvant chemotherapy +/- tamoxifen and 21% received tamoxifen alone. The median follow-up was 59 months (range 7-143). RESULTS: There were 5 chest wall recurrences at a median interval of 26 months (range 7-127). One was an isolated first failure, one occurred concurrent with an axillary recurrence, and three were associated with distant metastases. The 5- and 8-year cumulative incidences of a chest wall recurrence were 9% and 18%. Patient age correlated with the cumulative incidence of chest wall recurrence at 8 years; age < or = 50 years had a rate of 28% vs. 0% for age >50 (p = 0.04). There was no correlation with chest wall failure and number of positive nodes, ER status, lymphovascular invasion, location of primary, grade, family history, or type of tumor close to the margin. Of 5 chest wall failures, 4 were in patients who had received adjuvant systemic chemotherapy +/- tamoxifen. Chest wall failures occurred in 1 patient with a positive deep margin, 3 patients with margins within 2 mm, and 1 patient with a margin of 5 mm. The estimated cumulative incidence probability of chest wall recurrence at 8 years by margin proximity was 24% < or = 2 mm vs. 7% 2.1-6 mm (p = 0.36), and by clinical size 24% for T2 tumors vs. 7% for T1 (p = 0.98). CONCLUSIONS: A close or positive margin is uncommon (< or = 5%) after mastectomy in patients with tumor size <5 cm and 0-3 positive axillary nodes but, when present, it appears to be in a younger patient population. The subgroup of patients aged 50 or younger with clinical T1-T2 tumor size and 0-3 positive nodes who have a close (< or = 5 mm) or positive mastectomy margin are at high risk (28% at 8 years) for chest wall recurrence regardless of adjuvant systemic therapy and, therefore, should be considered for postmastectomy radiation.

Expression of the multidrug resistance gene in myeloid leukemias.

The human multidrug-resistance gene (MDR1) encodes an energy-dependent multidrug efflux protein responsible for the cross-resistance of cultured cells to natural product chemotherapeutic agents such as the anthracyclines and vinca alkaloids. RNA transcript levels were measured in leukemia cells obtained from 15 adult acute nonlymphocytic leukemia (ANLL) cases and 15 cases of chronic myelogenous leukemia (CML). Expression of MDR1 RNA was common in ANLL, and appears to be most frequent in leukemic cells of patients with the poorest response to chemotherapy. Expression of the MDR1 gene was not detectable in the peripheral white blood cells of any of the CML cases during the chronic phase, but was detectable in the immature cells present during this phase of the disease. The cells of the three blastic crisis patients contained detectable levels of MDR1 RNA. These studies support the idea that expression of the MDR1 gene contributes to drug resistance in ANLL, and may play a role in some instances in the drug-resistance of CML in blastic crisis. In contrast, studies of the level of expression of anionic glutathione transferase and DNA polymerase B failed to show any relationship between the RNA transcript levels of these enzymes and responsiveness to chemotherapy.

Retrospective diagnosis of sickle cell-hemoglobin C disease and parvovirus infection by molecular DNA analysis of postmortem tissue.

A previously healthy 30-year-old African-American woman presented with a history of sickle cell trait and a nonspecific prodromal illness with severe bone pain. She experienced rapid clinical deterioration with seizures and cardiorespiratory arrest leading to death. Autopsy showed necrotic bone marrow with extensive bone marrow emboli. Parvovirus infection was documented by polymerase chain reaction (PCR) although diagnostic intranuclear inclusions or giant pronormoblasts were not present. The diagnosis of sickle cell-hemoglobin C disease (hemoglobin SC disease) was also established postmortem by DNA sequencing of PCR products. This case illustrates the use and versatility of PCR for analysis of formalin-fixed paraffin-embedded autopsy tissue.

Stroke in surgery of the thoracic aorta: incidence, impact, etiology, and prevention.

OBJECTIVES: To determine the incidence, impact, etiology, and methods for prevention of stroke after surgery of the thoracic aorta. METHODS: A total of 317 thoracic aortic operations on 303 patients (194 male, 109 female) aged 13 to 87 years (mean 61 years) were reviewed. There were 218 procedures on the ascending aorta and arch and 99 on the descending aorta. Of the 218 procedures on the ascending aorta and arch, 86 involved cardiopulmonary bypass, 122 involved deep hypothermic circulatory arrest, 2 involved antegrade cerebral perfusion, and 8 involved "clamp and sew" or left heart bypass. Of the 99 procedures on the descending aorta, 20 involved "clamp and sew," 69 involved left heart or full bypass, and 10 involved deep hypothermic circulatory arrest. A total of 206 cases were elective and 97 were emergency operations. RESULTS: Twenty-three (7.3%) of 317 patients had a stroke. Fifteen strokes occurred in operations on the ascending aorta and 8 in operations on the descending aorta (6.9% vs 8.1%; P =.703). Stroke occurred in 16 (16.5%) of 97 emergency operations and 7 (3.4%) of 206 elective operations (P =.001). In the 300 patients surviving the operation, stroke was a significant predictor of postoperative death (9/23 [39.1%] vs 23/277 [8.3%]; P =.001). Analysis of operative reports, brain images, and neurologic consultations revealed 15 of the 23 strokes were embolic, 3 were ischemic, 3 hemorrhagic, and 2 indeterminate. Patients with stroke had longer intensive care unit stays (18.4 vs 6.8 days; P =.0001), longer times to extubation (12.7 vs 3.8 days; P <.0012), longer postoperative stays (31.4 vs 14.3 days; P =.001), and decreased age-adjusted survival (relative risk 2.775; P =.0013). After implementation of a rigorous antiembolic regimen, both strokes and mortality trended downward. CONCLUSIONS: (1) Stroke complicates surgery of both the ascending and descending thoracic aorta and warrants consideration in decision making. (2) Strokes are largely embolic. (3) Antiembolic measures for particles and air are essential, including gentle aortic manipulation, thorough debridement, transesophageal echocardiography to identify aortic atheromas, carbon dioxide flooding of the field, and (in descending cases) proximal clamp application before initiating femoral perfusion.

Economic analysis of conventional-dose chemotherapy compared with high-dose chemotherapy plus autologous hematopoietic stem-cell transplantation for metastatic breast cancer.

We performed an economic analysis of data from 180 women in a clinical trial of conventional-dose chemotherapy vs high-dose chemotherapy plus stem-cell transplantation for metastatic breast cancer responding to first-line chemotherapy. Data on resource use, including hospitalizations, medical procedures, medications, and diagnostic tests, were abstracted from subjects' clinical trial records. Resources were valued using the Medicare Fee Schedule for inpatient costs at one academic medical center and average wholesale prices for medications. Monthly costs were calculated and stratified by treatment group and clinical phase. Mean follow-up was 690 days in the transplantation group and 758 days in the conventional-dose chemotherapy group. Subjects in the transplantation group were hospitalized for more days (28.6 vs 17.8, P=0.0041) and incurred higher costs (US dollars 84055 vs US dollars 28169) than subjects receiving conventional-dose chemotherapy, with a mean difference of US dollars 55886 (95% CI, US dollars 47298-US dollars 63666). Sensitivity analyses resulted in cost differences between the treatment groups from US dollars 36528 to US dollars 75531. High-dose chemotherapy plus stem-cell transplantation resulted in substantial additional morbidity and costs at no improvement in survival. Neither the survival results nor the economic findings support the use of this procedure outside of the clinical trial setting.