Evaluation of clinical significance of basal-like subtype of breast cancer identified by immunohistochemistry

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Background: At present time, prognostic evaluation of initial breast cancer is mostly based on patients’ clinical and tumoral histological features. Recently, molecular subtypes of invasive breast cancer were recognized through DNA microarray profiling studies. This new classification can potentially improve the prognostic evaluation but this technology is still not widely available. The possibility of identifying the molecular subtypes through simpler and cheaper methods is promising. The identification of basal-like breast cancer (BLBC) is particularly important because it has a poor outcome and fewer treatment options available. Additionally, Epidermal Growth Factor Receptor (EGFR) expression seems to be more frequent in this subtype. Methods: A retrospective cohort of 112 consecutive patients with pathologic stage I or II primary breast carcinomas, treated in the same institution between 1995 and 2000, was studied. Histological and clinical features as well as clinical outcome and survival were reviewed. Immunohistochemical analysis was carried out in representative blocks of tumors with antibodies against Estrogen Receptor (ER), Human Epidermal Growth Receptor - type 2 (HER2), CK5/6 and EGFR. The primary endpoint was to determine the prevalence of BLBC (ER and HER2-negative and CK 5/6 and/or EGFR-positive) in this population. Results: 13 of 112 tumors (11,6 %) were BLBC. Their mean age was 49 years; 77 % were stage II and 100 % were invasive ductal carcinomas. There was no prognostic difference between BLBC and the subtypes luminal (ER-positive and HER2-negative); HER2-overexpressing (HER2-positive) and undetermined (four markers negative) relating to disease-free and overall survival. This is probably related to limited number of patients in this study and good prognosis of initial-stage patients. 11 of 112 cases (10%) were positive for EGFR. EGFR-positive tumors tended to be ER- negative (23 % vs 5 %; p=0,01). Conclusions: Our results suggest that it is possible to identify BLBC by immunohistochemical analysis of ER, HER2, CK 5/6 and EGFR. Besides, EGFR expression seems to be more frequent in ER-negative tumors, which suggest EGFR-targeted drugs may benefit this population.

No significant financial relationships to disclose.

Herpes simplex virus type 2 and Chlamydia trachomatis in adenocarcinoma of the uterine cervix

INTRODUCTION

Adenocarcinoma of the uterine cervix (AC) occurs in 15-20% of primary cervical neoplasias. Although some etiologic factors for squamous cell carcinoma are well defined, and its relationship with sexually transmitted disease as human papillomavirus (HPV) is established, we still do not know about the causative factors of most of AC besides HPV infection.

OBJECTIVES

To determine the presence of herpes simplex virus type 2 (HSV-2) and Chlamydia trachomatis (CT) DNA in AC specimens, and its correlation with HPV infection.

METHODS

206 paraffin-embedded cases of AC were selected to DNA extraction. The specimens and the DNA were isolated. Samples were first screened for beta-globin DNA sequences, and 67 cases were considered adequate to further analysis. In a previous analysis, DNA of HPV was identified in 79.4% of specimens included in this series (51% HPV 18 and 34% HPV 16). The local ethical committee approved the study.

RESULTS

All samples were negative for HSV-2 DNA and CT DNA.

CONCLUSIONS

In our series HSV-2 DNA and CT DNA were not found to be integrated to the genome of adenocarcinoma of the uterine cervix and do not seem to be a co-factor for HPV on the etiology of this histologic subtype.

Accuracy of frozen-section analysis in the diagnosis of ovarian tumors: a systematic quantitative review

A quantitative systematic review was performed to estimate the diagnostic accuracy of frozen sections in ovarian tumors. Studies that compared frozen sections and paraffin sections within subjects for diagnosis of ovarian tumors were included. Fourteen primary studies were analyzed, which included 3 659 women. For benign ovarian vs borderline/malignant tumor cases, the occurrence of a positive frozen-section result for benignity (pooled likelihood ratio [LR], 8.7; 95% confidence interval [CI], 7.3-10.4) and posttest probability for benign diagnosis was 95% (95% CI, 94-96%). A positive frozen-section result for malignant vs benign diagnosis (pooled LR, 303; 95% CI, 101-605) increased the probability of ovarian cancer to 98% (95% CI, 97-99%). In borderline vs benign ovarian tumor cases, a positive frozen-section result (pooled LR, 69; 95% CI, 45-106) increased the probability of borderline tumors to 79% (95% CI, 71-85%). In borderline vs malignant ovarian tumor cases, a positive frozen-section result (pooled LR, 18; 95% CI, 13-26) increased the probability of borderline tumors to 51% (95% CI, 42-60%). We conclude that diagnostic accuracy rates for frozen-section analysis is high for malignant and benign ovarian tumors, but the accuracy rates in borderline tumors remain relatively low.

Accuracy of frozen-section analysis in the diagnosis of ovarian tumors: a systematic quantitative review

A quantitative systematic review was performed to estimate the diagnostic accuracy of frozen sections in ovarian tumors. Studies that compared frozen sections and paraffin sections within subjects for diagnosis of ovarian tumors were included. Fourteen primary studies were analyzed, which included 3 659 women. For benign ovarian vs borderline/malignant tumor cases, the occurrence of a positive frozen-section result for benignity (pooled likelihood ratio [LR], 8.7; 95% confidence interval [CI], 7.3–10.4) and posttest probability for benign diagnosis was 95% (95% CI, 94–96%). A positive frozen-section result for malignant vs benign diagnosis (pooled LR, 303; 95% CI, 101–605) increased the probability of ovarian cancer to 98% (95% CI, 97–99%). In borderline vs benign ovarian tumor cases, a positive frozen-section result (pooled LR, 69; 95% CI, 45–106) increased the probability of borderline tumors to 79% (95% CI, 71–85%). In borderline vs malignant ovarian tumor cases, a positive frozen-section result (pooled LR, 18; 95% CI, 13–26) increased the probability of borderline tumors to 51% (95% CI, 42–60%). We conclude that diagnostic accuracy rates for frozen-section analysis is high for malignant and benign ovarian tumors, but the accuracy rates in borderline tumors remain relatively low.

Evidence for a common etiology for endometrial carcinomas and malignant mixed mullerian tumors

OBJECTIVE

To elucidate factors linked to the development of malignant mixed mullerian tumors (MMMT) and determine whether the risk factor profile for these tumors corresponds with that for the more common endometrial carcinomas.

METHODS

A multicenter case-control study of 424 women diagnosed with endometrial carcinoma, 29 women diagnosed with MMMT, and 320 community controls was conducted. Review of pathological reports and slides was performed to classify cases by histological type. All participants were asked to respond to a questionnaire which ascertained information on exposure to factors postulated to be linked to the development of uterine tumors.

RESULTS

Women with endometrial carcinomas and MMMTs were similar with respect to age and educational attainment. Women diagnosed with MMMTs were more likely than those diagnosed with carcinomas to be of African-American descent (28% vs 4%; P = 0.001). Weight, exogenous estrogen use, and nulliparity were related to risk of both tumor types. Marked obesity was associated with a 4.8-fold (95% CI = 3.0,7.6) increase in risk of carcinoma and a 3.2-fold (95% CI = 1.1,9.1) increase in risk of MMMT development. Use of exogenous estrogens increased the odds of developing carcinomas by 2-fold (95% CI = 1.3,3.2) and that of developing MMMTs by 1.8-fold (95% CI = 0.57,5.5). Nulliparity was associated with a 2.9-fold (95% CI = 1.9,4.8) increase in risk of carcinomas and a 1.7-fold (95% CI = 0.53,5.6) increase in risk of MMMTs. Oral contraceptive use protected against the development of both carcinomas (OR = 0.39; 95% CI = 0.26,0.58) and MMMTs (OR = 0.76; 95% CI = 0.25,2.3). Current smokers were at a reduced risk of developing endometrial carcinomas (OR = 0.34; 95% CI = 0.21,0.55) and MMMTs (OR = 0.57; 95% CI = 0.15,2.3), while former smokers were at an increased risk of MMMT (OR = 2.7; 95% CI = 1.1,6.8) but not carcinoma development (OR = 0.81; 95% CI = 0.56,1.2).

CONCLUSION

Results from this study suggest that MMMTs and carcinomas have a similar risk factor profile. This observation is compatible with the hypothesis that the pathogenesis of these two histological types of uterine tumors is similar.

Social inequality in mortality in São Paulo State, Brazil

BACKGROUND

Epidemiological studies have consistently demonstrated social inequality to be an important factor in the distribution of illness and death in society. However, little work has been published on social differentials in mortality in the world's developing countries, where socioeconomic contrasts are often considerably greater.

METHODS

In order to evaluate the extent of social differentials in mortality in a setting of major social inequality -- the State of São Paulo, Brazil, deaths in men aged 15-64 years residing in São Paulo from 1980 to 1982 were linked in broad, occupationally-determined categories to estimates of population size based on the 1980 Brazilian national census. The occupational categorizations utilized a Brazilian classification scheme and additionally that of the British Registrar General.

RESULTS

Mortality was 3.8 and 2.9 times greater comparing least to most socially favoured occupational category in each of the two classification systems, respectively. Independent of system, mortality decreased approximately 1.1% for each 1% increase along the occupationally-defined social gradient. This decrease was 48% greater than the equivalent calculated decrease for men of England and Wales.

CONCLUSIONS

These data support the contention that mortality for Brazilian adults, even more so than for adults of the world's more economically developed nations, is inextricably bound to the issue of social equity.