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B Têtu

Publications and source records attributed to B Têtu.

At least 55 records · Page 3Linked to original sources
PubMed1995

Prognostic significance of heat-shock protein-27 in node-positive breast carcinoma: an immunohistochemical study.

Immunostaining for heat-shock protein-27 (HSP-27) was performed on formalin fixed-paraffin embedded sections of 890 node-positive breast carcinomas resected between 1980 and 1986. The follow-up ranged from 2.5 to 10.5 years. A polyclonal antibody (Hu27, dilution: 1/200) was used. A positive cytoplasmic staining was obtained in 383 cases (43%). No difference in distant metastasis-free survival (DMFS) or overall survival (OS) was noted between cases with positive or negative immunostaining. This study suggests that HSP-27 expression is not predictive of the outcome in node-positive breast cancer.

Breast Neoplasms↗
PubMed1995

Downstaging by combination therapy with flutamide and an LHRH agonist before radical prostatectomy.

A total of 161 patients diagnosed as having stage B (134 patients) or C (27 patients) prostate cancer were randomly assigned to radical prostatectomy alone or to 3 months of neoadjuvant combination therapy with the anti-androgen flutamide and an LHRH agonist before radical prostatectomy. Neoadjuvant combination therapy before radical prostatectomy decreased cancer positive surgical margins from 33.8% in the control group to only 7.8%, thus leaving 92.2% of patients with negative margins at surgery for a 39.2% increase in specimen confined disease. Although on average the final stage determined at histopathological examination of the surgical specimen was more advanced than predicted at initial diagnosis in 33.8% of control patients, an opposite observation was made in the group of men who received the 3 month neoadjuvant combination therapy where the final stage, instead of being more advanced, was less advanced than at diagnosis in an average of 21.1% of men for a net 54.9% improvement of staging in favour of combination therapy. On the other hand, organ confined disease increased from 49.3% to 77.8% of patients after 3 months of combination therapy, for a 57.9% increase in the incidence of organ confined disease. Although long term follow up of these patients is required to determine the impact on survival, the marked influence of neoadjuvant combination therapy on the stage of the disease suggests the possibility of a major improvement in the morbidity and mortality from prostate cancer.

Aged↗
PubMed1995

Tumor-associated antigens as prognostic factors for recurrence in 382 patients with primary transitional cell carcinoma of the bladder.

This prospective study was designed to assess the prognostic value of tumor-associated antigens, designated 19A211, M344, T138, and T43, with respect to recurrence of primary superficial bladder cancer. Between September 1990 and April 1992, all patients with primary superficial bladder tumors treated by endoscopic resection in 15 participating hospitals were enrolled. Immunostaining for 19A211 and M344 was performed on paraffin-embedded material, and for T43 and T138 on frozen tissue. Antigenic expression was evaluated blindly by a single pathologist. Patients were followed up with the standard schedule of control cystoscopies. Cox regression was used to estimate hazard ratios (HRs) for first recurrence, and Poisson regression was used to estimate recurrence rate ratios and tumor rate ratios adjusted for primary tumor characteristics. By March 1994, 2254 follow-up cystoscopies had been performed on 368 of the 382 study patients, and tumor recurrence was detected in 55.7% of patients. Positivity to 19A211 was detected in 90% of primary tumors, its expression being associated with a decrease in first recurrence hazard ]HR, 0.65; 95% confidence interval (CI), 0.42-1.03] and in recurrence rate (recurrence rate ratio, 0.70; 95% CI, 0.53-0.92). Positivity to T138 was detected in 15% of tumors, and its expression was associated with an increase in first recurrence hazard (HR, 1.43; 95% CI, 0.92-2.22) and in recurrence rate (recurrence rate ratio, 1.31; 95% CI, 1.00-1.72). Positivity to M344 was detected in 71% of tumors, and its expression was associated with an increase in tumor rate (tumor rate ratio, 1.77; 95% CI, 1.41-1.97). T43 expression was not associated with recurrence end points. In conclusion, recurrence of superficial bladder cancer was associated with antigenic expression of 19A211, T138, and M344, independently of primary tumor characteristics.

Adult↗
PubMed1994

Prognostic significance of HER-2/neu oncoprotein expression in node-positive breast cancer. The influence of the pattern of immunostaining and adjuvant therapy.

BACKGROUND: The influence of HER-2/neu on prognosis of breast cancer is controversial. The authors investigated by immunohistochemistry in node-positive disease the influence of the pattern of immunostaining (membranous or cytoplasmic) on outcome and the prognostic significance of this marker in patients receiving or not receiving adjuvant therapy. METHODS: The immunostaining for HER-2/neu oncoprotein was performed on formaldehyde-solution-fixed, paraffin-embedded sections of 888 node-positive breast cancers resected between 1980 and 1986 and for which a follow-up of 2.5-10.5 years was available. The staining was performed using a polyclonal antibody (dilution, 1/15). RESULTS: One hundred forty-three cases (16.1%) revealed a positive membrane staining with or without additional cytoplasmic contribution, whereas cytoplasmic staining alone was noted in 118 cases (13.3%). Positive membrane staining was correlated with more involved lymph nodes (P = 0.005), aneuploidy (P = 0.002), poor nuclear (P < 0.0001) and histologic (P = 0.007) grades, absence of estrogen (P < 0.0001) and progesterone (P < 0.0001) receptor content, and cathepsin D expression (P = 0.009). No relation was found (P > 0.05) with either age, tumor size, or HSP27 expression. Membrane staining was strongly associated with poor distant metastasis-free or overall survival rate (P < 0.0001), whereas cytoplasmic staining had no prognostic significance. Two hundred thirty-two patients (26.1%) received no additional treatment after surgery. The difference in survival rates between cases with positive and negative staining was only significant among patients submitted to adjuvant chemotherapy or hormone therapy. CONCLUSIONS: This study strongly supports the association of HER-2/neu oncoprotein expression with poor prognosis in node-positive breast cancer and demonstrates that membranous but not cytoplasmic staining is prognostically relevant. It also shows that HER-2/neu oncoprotein expression is useful in predicting survival time only in patients receiving adjuvant therapy, thus suggesting that it may be a marker of drug resistance.

Adult↗
PubMed1994

Morphologic prognostic factors of malignant mixed müllerian tumors of the ovary: a clinicopathologic study of 15 cases.

Fifteen ovarian malignant mixed müllerian tumors (MMMT) of the ovary are reported in an attempt to identify morphologic factors of prognostic interest. Several features were correlated to survival: histologic subtype and nuclear and histologic grades of the epithelial component; histologic subtype, grade, and mitotic rate of the mesenchymal component; necrosis and epithelial-to-mesenchymal ratio. The epithelial component was mainly of endometrioid (four cases) and serous (four cases) types. The mesenchymal component was largely heterologous, of which five were of chondromatous and five of rhabdomyoblastic differentiation. This latter differentiation was further demonstrated by electron microscopy (two cases) and immunohistochemistry (four cases). Ten tumors showed hyaline droplets that stained for alpha 1-antitrypsin in two cases. Eight patients died of their disease, 13 days to 32 months after diagnosis (median, 5 months). Seven were alive 3 to 49 months (median, 10 months) after initial therapy. No morphologic factor was found to correlate with survival, but a tendency was observed for ovarian MMMTs with a high epithelial nuclear grade, a predominance of the mesenchymal component, or a rhabdomyoblastic mesenchymal component to be associated with more aggressive behavior. The histologic appearance of metastases did not correlate with prognosis.

Aged↗
PubMed1993

Prognostic significance of cathepsin-D expression in node-positive breast carcinoma: an immunohistochemical study.

The prognostic significance of cathepsin-D expression was evaluated by immunohistochemistry in 638 node-positive breast carcinomas diagnosed between 1980 and 1986. A minimum of 2.5 years of follow-up was available for each patient (maximum: 9.5 years). Cathepsin-D expression was assessed separately both in cancer and in stromal cells using a commercially available polyclonal antibody. While cancer-cell immunostaining was not associated with prognosis, positive staining of stromal elements was related to shorter metastasis-free survival. The difference in distant metastasis-free survival between positive and negative expressors was greatest in the sub-group of patients submitted to adjuvant chemotherapy, with a hazard ratio for occurrence of distant metastasis of 1.76 by multivariate analysis, but was lowest for those receiving hormone therapy. Cathepsin-D expression by stromal cells was related to HER-2/neu oncoprotein expression, HSP-27 expression, poor nuclear grade, aneuploidy, and absence of estrogen and progesterone receptors. No association was found with the number of involved lymph nodes, tumor size, age, histologic grade, S-phase fraction, or vascular invasion. Our study suggests that cathepsin-D expression by stromal cells (and not by cancer cells) affects the prognosis of breast cancer, that stromal cells probably play a key role in local invasion and metastatic dissemination of the tumor, and that the prognostic significance of cathepsin-D expression may vary according to the type of adjuvant therapy.

Adult↗
PubMed1993

High levels of P-glycoprotein detected in isolated brain capillaries.

P-glycoprotein (P-gp) is a highly-conserved membrane protein expressed in various multidrug-resistant cell lines. P-glycoprotein was detected in capillaries isolated from human, beef and rat brains with a Western immunoblotting procedure using the monoclonal antibody C219 (mAb C219) specific for P-gp. The mAb C219 detected a 180 kDa protein in brain capillaries isolated from all three species. The largest amount of antigen was detected in capillaries isolated from human brain. Specific binding was assessed by competitive inhibition of mAb C219 binding by the synthetic epitope VQEALD. The glycoprotein nature of the brain capillary proteins was confirmed by its sensitivity to N-glycanase treatment, which reduced their apparent molecular mass by 5 to 10 kDa. In addition, immunohistochemical studies using the antibodies C219, JSB-1 and C494 were performed. Bovine and rat capillaries showed reactivity only with the mAb C219. Heavy staining of human brain capillaries was observed with both antibodies C219 and JSB-1, while only weak staining was observed with antibody C494. These results clearly show that P-glycoprotein is strongly expressed at the blood-brain barrier (BBB) site and suggest that this protein may play a physiological role in regulating the access of certain molecules to the central nervous system, or in the secretory functions of the BBB.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1993

Juxtaglomerular cell tumor of the kidney: report of two cases with a papillary pattern.

We report the clinicopathologic, immunohistochemical, and electron microscopic study of two cases of juxtaglomerular cell tumor of the kidney with a hitherto unreported dominant papillary pattern. Both tumors were associated with high blood pressure that did not respond to medical therapy, but that returned to normal after removal of the kidney. They were well delineated, tan, and had no necrosis. The cores of the papillary structures consisted of polygonal cells found to express renin by immunohistochemistry and to contain renin protogranules by electron microscopy. The papillary fronds were covered by one layer of cuboidal epithelial cells that did not stain for renin and had ultrastructural features reminiscent of the collecting duct epithelium. These tumors must be differentiated from malignant papillary tumors of the kidney, such as papillary clear cell carcinoma, transitional cell carcinoma, and collecting duct carcinoma.

Adenocarcinoma↗
PubMed1993

Downstaging of localized prostate cancer by neoadjuvant therapy with flutamide and lupron: the first controlled and randomized trial.

Although the only opportunity to cure prostate cancer is treatment at an early stage, radical prostatectomy has remained relatively unpopular because 40-50% of prostate cancers estimated at diagnosis as confined to the prostate are found to be at a more advanced stage following histopathological analysis of the surgical specimen. This first prospective, randomized trial investigated the potential advantages of 3-month neoadjuvant combination therapy with flutamide and lupron before radical prostatectomy vs. prostatectomy alone in early stage prostate cancer. Cancer-positive margins were reduced from 38.5% (25 of 65) in control patients to only 13.0% (10 of 77) in men who received neoadjuvant combination therapy with the antiandrogen flutamide and the luteinizing hormone-releasing hormone (LHRH) super-agonist Lupron before radical prostatectomy (p = 0.006). Moreover, comparison of the final stage determined by histopathological examination of the surgical specimen with that estimated at diagnosis showed that a more advanced stage (upstaging) was found in 53.8% of controls, but patients who received combination therapy had an opposite effect: a more favorable stage than expected at diagnosis was found in 23.4% of cases (downstaging), a 77.2% advantage of neoadjuvant combination therapy. The concern about radical prostatectomy, underestimation of stage, is thus markedly improved by 3-month neoadjuvant therapy with flutamide and a LHRH superagonist. Cancer-negative margins are expected to be accompanied by a life expectancy not different from that of men of similar age with no prostate cancer; therefore, the present data, combined with efficient detection of early stage prostate cancer, offer the basis for dramatic improvement in the morbidity and mortality of prostate cancer.

Adenocarcinoma↗
PubMed1992

Sarcomatoid carcinoma of the prostate. A clinicopathologic study of 12 patients.

Sarcomatoid carcinoma of the prostate is a rare tumor that can be difficult to distinguish from a true sarcoma. The authors report 12 patients in whom the typical light microscopic appearance of prostatic adenocarcinoma was accompanied by the appearance of spindled or pleomorphic sarcomatoid areas within the same specimen or in subsequent accessions. Immunostaining or electron microscopic study demonstrated epithelial differentiation within the sarcomatoid area(s) in 6 of the 11 patients in whom special studies were performed. All nine patients for whom follow-up data were available died of disease within 3 to 48 months (median time until death, 12.0 months) after the appearance of the sarcomatoid carcinoma, and the clinical course in each instance was characterized by aggressive local recurrence. Our experience confirms that sarcomatoid carcinoma of the prostate is an aggressive variant of prostatic adenocarcinoma.

Aged↗
PubMed1992

Prognostic influence of HSP-27 expression in malignant fibrous histiocytoma: a clinicopathological and immunohistochemical study.

Malignant fibrous histiocytoma is a very aggressive sarcoma. After the tumor has disseminated, chemotherapy is of little influence on the course of the disease because of the resistance to most chemotherapy regimens. We evaluated by immunohistochemistry the prognostic influence of the expression of a member of the stress polypeptides family, the heat-shock protein of 27 KDa (HSP-27). HSP-27 was found to be associated with an aggressive behavior in breast carcinoma and was related to chemoresistance in cell cultures. Forty-three malignant fibrous histiocytomas with no evidence of metastases at the time of diagnosis and resected between 1974 and 1985 were retrieved from the files of the Pathology Department of L'Hôtel-Dieu de Québec hospital. The immunostaining was performed on Bouin-fixed, paraffin-embedded tissue. Regardless of the percentage of positive cells, HSP-27 was expressed in the cytoplasm of 25 (58.1%) cases. HSP-27 expression was associated with a more favorable prognosis, and a significant correlation was observed with overall survival (P less than 0.025) and metastasis-free survival (P less than 0.05). HSP-27 expression was found to be the strongest prognostic factor, and multivariate analysis revealed that it was independent of tumor size, necrosis, and histological subtype. However, in the 13 patients with recurrent disease who underwent chemotherapy, the antigenic expression did not help to predict the treatment response. HSP-27 expression is one of the rare prognostic markers in this tumor type.

Adolescent↗
PubMed1992

Transrectal ultrasound evaluation of local prostate cancer in patients treated with LHRH agonist and in combination with flutamide.

We followed total prostate and prostatic tumor volumes in patients who received combination endocrine therapy with the antiandrogen flutamide and the LHRH agonist [D-Trp6,des-Gly-NH2(10)]LHRH ethylamide. Twenty-three men with proved prostatic adenocarcinoma (Stages B1 to D2) were subjected to a transrectal ultrasound (TRUS) study before and after a three-month period of combination antihormonal therapy. A total prostatic volume reduction ranging from 17 percent to 70 percent (median 47%, p less than 0.0001) was observed. An even greater effect was observed on tumor volume which was reduced by 20 percent to 91 percent (median 81%, p less than 0.01). After treatment, the original suspicious zone became nonvisible in 4 cases. The TRUS measurements were confirmed by direct examination of the radical prostatectomy specimen in 7 cases. TRUS is thus a precise, sensitive, and valid method for evaluating the effect of combined antihormonal therapy on normal and tumoral prostatic tissues. These data indicate that combination therapy induces a rapid and marked reduction in glandular and tumoral prostatic volume which could well improve the success of radical prostatectomy and increase the changes of cure of localized prostatic cancer.

Adenocarcinoma↗
PubMed1991

Ovarian myxoma. A study of two cases with long-term follow-up.

Two cases of the so-called ovarian myxoma are reported. One was from a 13-year-old girl who had a 31-year follow-up and no evidence of recurrence. The second case, from a 65-year-old woman, recurred intraperitoneally, 19 years after the surgery. Both tumors were myxoid, with round to stellate cells. Immunohistochemical, electron microscopic (EM), and DNA flow cytometric (FCM) studies were performed on formalin-fixed, paraffin-embedded tissue of the second patient on both the primary tumor and the recurrence. Tumor cells expressed vimentin and were focally positive for desmin and myoglobin. EM findings suggested a fibroblastic differentiation. An aneuploid cell population was present in the recurrent tumor by DNA-FCM studies. Only four other cases of so-called ovarian myxoma were reported to date, and the follow-up does not exceed 18 months. The authors conclude that the presence of aneuploidy and the late recurrence of one of their cases suggest that certain ovarian myxomas might behave like low-grade sarcomas. The histogenesis of this tumor remains unsettled, but similarities were found with myxomas in other locations.

Adolescent↗
PubMed1991

Effect of combination endocrine therapy (LHRH agonist and flutamide) on normal prostate and prostatic adenocarcinoma. A histopathologic and immunohistochemical study.

The histopathology of 23 radical prostatectomies from patients with prostatic adenocarcinoma pretreated for 3-6 months with combination therapy including a luteinizing hormone-releasing hormone agonist and the antiandrogen drug flutamide was reviewed and compared with the pretreatment biopsies or transurethral resection material. After combination therapy, benign prostatic glands showed marked atrophy with prominent basal-cell layers, basal-cell hyperplasia, and epithelial-cell vacuolization. Immature squamous-cell metaplasia was present in seven cases. Residual carcinoma, on the other hand, was found in 19 of the 23 cases, and in 8 of these, tumor cells were either vacuolated or had scanty cytoplasm. Residual tumor was present as only one focus in 13 cases, and in 3 of these it was composed of single cells with a "hemangiopericytoma-like" pattern. An immunohistochemical study for prostatic acid phosphatase and prostatic-specific antigen could be carried out on paraffin blocks from 19 biopsies and 18 prostatectomies. After combination therapy, a reduction in staining (intensity and number of positive cells) was observed for the two markers in both normal prostate and carcinoma but with more pronounced effects on the latter. The present data show that temporary combination therapy before radical prostatectomy causes marked and very characteristic changes in normal prostatic tissue as well as in the prostatic tumor. These histologic patterns enter the differential diagnosis of a variety of atrophic, metaplastic, and proliferative lesions of the prostate gland. The pathologist must be aware of these histologic changes when looking at biopsy or resection material of treated patients.

Adenocarcinoma↗
PubMed1991

Endocervical involvement by endometrial carcinoma on fractional curettage: a clinicopathological study of 37 cases.

This is a retrospective study of 37 patients with endometrial carcinoma and presence of tumor on endocervical curettage (clinical Stage II). We intended to correlate the presence or absence of endocervical stromal invasion with the clinical behavior and other prognostic factors. Based on the endocervical curettage, three categories (CAT) were defined: CAT I: tumor fragments only (seven cases); CAT II: endocervical tissue and free-floating tumor fragments (13 cases); and CAT III: endocervical tissue and tumor with evidence of stromal invasion (17 cases). Five tumors were partly of clear cell and/or papillary serous types and three of them belonged to CAT I. Six of seven tumors with a nuclear Grade 3 were in CAT III (p less than 0.05). Nine patients had local recurrence, metastases, or died of their disease (median follow-up: 56 mo) and seven of them were in the CAT III (p less than 0.05). We conclude that despite the presence of tumor on the endocervical curettage, the lack of endocervical tissue invasion is associated with a lower nuclear grade and a less aggressive behavior. These tumors should be regarded and treated as Stage I disease. Special attention must be paid to staging of clear cell and papillary serous adenocarcinomas because of the tendency for these tumors to contaminate the endocervical curettage.

Adenocarcinoma↗
PubMed1990

Expression of Zn-alpha 2-glycoprotein and PSP-94 in prostatic adenocarcinoma. An immunohistochemical study of 88 cases.

Zn-Alpha 2-Glycoprotein (Zn-Alpha 2-GP) and prostatic secretory protein of 94 amino-acids (PSP-94) were recently isolated from the human prostate. Their expression in benign and malignant well-differentiated and poorly differentiated components of 88 prostates with prostatic adenocarcinomas, and in 25 metastases, was evaluated using polyclonal antibodies developed against these antigens. Zn-Alpha 2-GP was present in benign hyperplastic glands in 91.1% of cases, but in only 40.7% (poorly differentiated component) to 48.5% (well-differentiated component) of prostatic adenocarcinomas, and in 8% of metastases. The expression of PSP-94 was present in 89.3% of benign hyperplastic glands, but in only 50% (well-differentiated adenocarcinoma component) to 57.3% (poorly differentiated component) of prostatic adenocarcinomas and 28% of metastases. The expression of these proteins by the tumor was unrelated to the initial stage and the tumor grade. Because of their low frequency in prostatic adenocarcinomas, especially in metastases, Zn-Alpha 2-GP and PSP-94 appear to have a limited diagnostic usefulness. Further studies are needed, however, to explore other clinical applications of these two new prostatic secretory proteins.

Adenocarcinoma↗
PubMed1989

Ovarian metastases of breast carcinoma. A clinicopathologic study of 59 cases.

Of 165 ovarian metastases recorded in the files of L'Hôtel-Dieu de Québec, Canada, between 1951 and 1987, 64 (38%) were from breast adenocarcinomas. Histopathologic material was available in 59 instances, of which 22 were autopsy cases and 28 were incidental findings at therapeutic oophorectomy. The patients' ages ranged from 25 to 80 years (average, 48.6 years). Sixty-four percent of the metastases were bilateral and 36% were unilateral. An ovarian metastasis was detected before the breast cancer in only one instance. The median interval between the diagnosis of breast carcinoma and the ovarian metastasis was 11.5 months and was related to the initial stage of the breast disease. The median survival after the diagnosis of ovarian metastasis was 16 months. The ovaries were grossly normal in 27 (46%) cases and 18 (31%) metastases were less than 1 mm in diameter. The size of the metastases was not related to the interval after the diagnosis of the breast carcinoma and did not influence the outcome of the patients. Forty-four metastases (75%) showed an indian file or ductal patterns easily identifiable as metastases of breast origin. The remaining cases presented various histologic features mimicking primary ovarian tumors or tumor-like conditions such as stromal luteoma, hyperthecosis, dysgerminoma, granulosa cell tumor, and carcinoid tumor. No metastasis had features of Krukenberg tumor. The authors conclude that metastases from breast cancer are generally small and are the reflection of an advanced disease. A metastasis of breast origin can be suspected histologically in most cases.

Adenocarcinoma↗