Endometrial adenocarcinoma of endometrioid subtype with squamous differentiation: an immunohistochemical study of MIB-1 (ki-67 paraffin), cathepsin D, and C-erbB-2 protein (p185)

Prevalence of Human Papillomavirus in endometrial cancer: a systematic review and meta-analysis

OBJECTIVE

HPV is a common sexually transmitted infection and is considered to be a necessary cause of cervical cancer. The anatomical proximity to the cervix has led researchers to investigate whether Human Papillomavirus (HPV) has a role in the etiology of endometrial cancer.

METHODS

We conducted a systematic review and meta-analysis to investigate the pooled prevalence of HPV DNA in endometrial cancer. Using meta-regression, we further analyzed whether factors such as geographical region, HPV DNA detection method, publication year and tissue type were associated with HPV prevalence. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for studies providing data on HPV prevalence in cases with endometrial cancer and in controls with normal or hyperplastic endometrial tissue.

RESULTS

We identified 28 papers (29 studies) examining the prevalence of HPV DNA in tumor tissue from endometrial cancer comprising altogether 1026 cases of endometrial cancer. The HPV prevalence varied considerably from 0% to 61.1%. From the random effects meta-analysis, the pooled prevalence of HPV DNA in endometrial cancer was 10.0% (95% CI: 5.2-16.2) with large between-study heterogeneity (I(2)=88.2%, p<0.0001). The meta-regression showed that HPV DNA detection method was statistically significantly associated with HPV prevalence (p=0.0016): the pooled HPV prevalence was 6.0% (95% CI: 1.5-13.0) using general primers, 18.9% (95% CI: 8.6-32.1) using type-specific primers and 1.0% (95% CI: 0.0-3.6) using non-PCR based methods. None of the other a priori defined variables were statistically significantly associated with HPV prevalence. The pooled OR was 1.43 (95% CI: 0.68-3.00) indicating that the odds of HPV was not increased in cases versus controls.

CONCLUSIONS

HPV appears to have a limited or no role in the etiology of endometrial cancer.

Squamous morules are functionally inert elements of premalignant endometrial neoplasia

Squamous morules are a common component of premalignant glandular lesions that are followed by glandular, rather than squamous, carcinomas. We tested the hypothesis that the appearance of glands associated with morules predicts cancer risk, and undertook molecular testing to determine the clonal and hormonal response properties of admixed squamous and glandular elements. A total of 66 patients with squamous morules in an index endometrial biopsy had follow-up clinical data (average follow-up: interval 31 months, 2.5 biopsies) showing development of carcinoma in 11% (7/66) of cases. The histological appearance of morule-associated glands in the index biopsy was significantly associated with this clinical outcome, with the majority (71%, 5/7) of cancer occurrences following an overtly premalignant lesion (endometrial intraepithelial neoplasia) with squamous morules. Eight endometrial intraepithelial neoplasias with squamous morules were examined by immunohistochemistry for estrogen and progesterone receptors and mitotic activity (Ki-67 antigen percent stained). Glandular components had abundant estrogen and progesterone receptors, and high levels of mitotic activity in all cases. In sharp contrast, all squamous morules were devoid of sex hormone receptors and had undetectable or extremely low-proliferation rates. When mutated, the same specific PTEN mutation was detected in squamous and glandular elements, indicating that both are of common lineage. The clinical and laboratory data are consistent with a model of morule biology in which squamous morules are a hormonally incompetent subpopulation of endometrial glandular lesions. Isolated morules might result from artifactual displacement from their native glandular context, or selective hormonally induced regression of the glandular but not squamous components over time. Subsequent cancer risk, as promoted by estrogens, is greatest when the glandular component has the appearance of endometrial intraepithelial neoplasia. Even isolated morules should be carefully followed, however, to exclude a coexisting undersampled, or occult, glandular lesion.

Immunohistochemical evaluation of cathepsin D in normal, hyperplastic and malignant endometrium: correlation with hormone receptor status c-erbB-2, p53, Rb proteins and proliferation associated indices

The immunohistochemical expression of cathepsin D was performed in paraffin embedded tissue from 79 endometrial carcinomas, 35 cases of hyperplasia, and 32 normal endometrium using the streptavidin-biotin method to investigate the role of cathepsin D (CD) in these lesions and its possible relationship with other potential and established prognostic markers. The association between CD and the other markers was assessed by univariate analysis. Tumor cell CD expression was lower in the group of carcinomas compared to the normal proliferative (P = 0.022) and secretory endometrium (P = 0.0005). In addition, hyperplastic cell CD expression was lower compared with epithelial cell CD expression in the secretory phase of normal endometrium (P = 0.009). Malignant cell CD expression was inversely correlated with tumor stromal cells (P = 0.007). A positive relationship of stromal cell CD expression with pRb (P = 0.046) and PCNA score (P < 0.0001) was detected in the group of carcinomas. In the proliferative phase of normal endometrium, epithelial CD expression was positively correlated with estrogen status (P = 0.015). The data show that down-regulation of CD expression is an early event in endometrial carcinogenesis. In addition, stromal cell CD expression may be involved in cell growth process in endometrial carcinomas.

Cathepsin D expression in normal, hyperplastic and malignant endometrial tissue: an immunohistochemical analysis

Cathepsin D (CathD), a lysosomal aspartyl protease secreted by normal and malignant cells, is considered to be involved in breakdown of the extracellular matrix. Aim of the present study was to determine the frequency and tissue distribution of CathD in normal, hyperplastic and malignant endometrium. Paraffin-fixed endometrial tissue was obtained from premenopausal women in the proliferative phase (n = 5), early secretory phase (n = 4) and late secretory phase (n = 4) as well as glandular-cystic hyperplasia (n = 5), endometrial polyps (n = 5), endometrial polyps from the use of tamoxifen (n = 5), adenomatous hyperplasia (AH) grade I (n = 5), grade II (n = 4), grade III (n = 5) and endometroid adenocarcinoma (n = 5). CathD expression was evaluated with the IRS score and ANOVA analysis was used for statistical evaluation. CathD was primarily localised in luminal and glandular epihelium with little staining in stromal cells. The expression of CathD was significantly higher during the late secretory phase than in the proliferative phase. Highest expression of CathD was observed in the late secretory phase and in glandular-cystic hyperplasia, whereas endometroid carcinoma showed no expression. A continuous increase in CathD expression was observed in AH, with a significant difference between AH grade I and III. In conclusion, CathD was found to be expressed in normal and hyperplastic endometrial tissue. CathD immunostaining in normal endometrial glands varied on the basis of the phase of the menstrual cycle, suggesting physiological functions of CathD in endometrial maturation and degradation. Adenocarcinomas did express significant lower amounts of CathD. Therefore, the prognostic value of this parameter remains uncertain. A continuous increase in CathD immunostaining was observed in AH. Since AH grade III can be considered as a precursor of endometrial cancer, CathD could be a possible parameter for assessing malignant transformation.

May cathepsin D immunoreactivity be used as a prognostic factor in endometrial carcinomas? A comparative immunohistochemical study

OBJECTIVE

To investigate the prognostic value of immunohistochemical detection of cathepsin D and the association between cathepsin D and established prognostic factors in endometrial carcinoma.

METHODS

Cathepsin D immunoreactivity was determined by an immunohistochemical technique in a series of 79 patients with surgical stage I-III primary endometrial carcinoma.

RESULTS

Of 79 tissue specimens, 48 (61%) showed a positive reaction for cathepsin D. A significant correlation between cathepsin D and histological grade was found (P < 0.05). The other established clinicopathological prognostic factors were not associated with cathepsin D. There was not any significant difference in prognosis between the positive cases and negative cases for cathepsin D (P > 0.05). In the univariate analysis cathepsin D immunoreactivity did not show significant prognostic value for overall survival (P > 0.05). The multivariate analysis also showed that cathepsin D was not related to patient outcome (P = 0.24, relative risk = 0.34, 95% confidence interval = 0.05-2.09).

CONCLUSIONS

Our results suggest that cathepsin D immunoreactivity may not be of prognostic value but more studies are needed to evaluate the relationship between its immunoreactivity in tumor cells and in other cells.

MIB-1 in endometrial carcinoma: prognostic significance with 5-year follow-up

OBJECTIVE

MIB-1, a monoclonal antibody to the Ki-67 antigen, has presumptively been shown to be predictive of recurrent disease in patients with endometrial cancer. In order to more conclusively establish whether MIB-1 staining can be used as a prognostic indicator of recurrent disease or survival, a larger group of patients with a minimum follow-up of 5 years was analyzed.

METHODS

The tumors from 147 consecutive patients receiving primary surgical therapy for endometrial carcinoma were evaluated with the MIB-1 monoclonal antibody. Proliferation index was quantified by image analysis. Patients were followed for a minimum of 60 months. In addition to MIB-1 staining, histologic type, stage, grade, depth of invasion, lymphovascular space invasion, and peritoneal cytology were evaluated as prognostic indicators.

RESULTS

Twenty-five of 147 patients died during the study period. MIB-1 staining was not significantly elevated in advanced (stage II, III, and IV) as opposed to early (stage I) carcinomas (P = 0.38). In patients whose tumor MIB-1 staining was less than 33.0%, no deaths occurred. By multivariate analysis, only MIB-1 staining (P < 0.001), FIGO stage (P = 0.005), and LVI (P = 0.005) were shown to be independent prognostic indicators predictive of survival.

CONCLUSION

In this series of 147 consecutive patients with endometrial carcinoma, the monoclonal antibody MIB-1 was shown to be an independent prognostic indicator of 5-year survival. This follow-up further validates the previous work regarding the significance and potential usefulness of MIB-1 as a prognostic indicator.

Immunohistochemical localization of lysosomal cathepsin D in schwannomas

The immunohistochemical localization of cathepsin D (CD) was demonstrated for the first time in 54 schwannomas (32 intra- and 22 extracranial; 47 benign and 7 malignant) and 5 normal nerve fibers. Granular or vesicular CD-reactive structures were observed in all normal Schwann cells. All tumors contained CD-reactive tumor cells, although the population of CD-reactive tumor cells, the density, intracellular localization, and morphology of CD-reactive structures, and the intensity of CD immunoreactivity varied from case to case, portion to portion, and cell to cell, differing variously from those in normal Schwann cells. The variations were greater in malignant than in benign schwannomas. In mildly degenerate tumor cells, CD immunoreactivity was increased, possibly in response to the increased intracellular degenerate proteins, suggesting that the mechanism of induction of lysosomal proteases preserved in normal cells is not affected by the process of neoplastic transformation. In lesions of severe degeneration or necrosis, CD immunoreactivity was lost in most tumor cells but was strong in macrophages invading the lesions and perivascular regions. CD immunoreactivity was observed at various intensities in tumor cells in the Antoni type A area but not in most tumor cells in the Antoni type B area, suggesting that Antoni type B lesions show degenerative changes. The presence of CD-reactive tumor cells in all tumors examined and strong CD immunoreactivity observed at the invasion front of tumors in some cases of benign or malignant schwannoma suggests the possible role of CD in tumor invasion in some cases.