HER-2 Is an Independent Prognostic Factor in Endometrial Cancer: Association With Outcome in a Large Cohort of Surgically Staged Patients

Hormonal heterogeneity of endometrial cancer

Endometrial cancer is the most common malignant tumor of the female genital tract in the developed world. Increasing evidence suggests that the majority of cases can be divided into two different types ofendometrial cancer based on clinico-pathological and molecular characteristics. Type I is associated with an endocrine milieu of estrogen predominance. These tumors are ofendometroid histology and develop from endometrial hyperplasia. They have good prognosis and are sensitive to endocrine treatment. Type II endometrial cancers are not associated with a history of unopposed estrogens and develop from the atrophic endometrium of elderly women. Mainly, they are of serous papillary or clear cell morphology, have a poor prognosis and do not react to endocrine treatment. Both types of endometrial cancer probably differ markedly with regard to the molecular mechanisms of transformation. The transition from normal endometrium to a malignant tumor is thought to involve a stepwise accumulation of alterations in cellular mechanisms leading to dysfunctional cell growth. This chapter reviews the current knowledge of the molecular mechanisms commonly associated with development of type I and type II endometrial cancer.

HER-2/neu and p27Kip1 in progression of Fallopian tube carcinoma: an immunohistochemical and array comparative genomic hybridization study

AIMS

To determine expression of p53, HER-2/neu and p27(Kip1) in serous Fallopian tube carcinoma (FTC) in relation to stage and grade, and to investigate DNA copy number changes of HER-2 and P27KIP1 as a potential mechanism of altered expression status.

METHODS AND RESULTS

Immunohistochemistry was performed on 28 serous FTCs and 10 normal Fallopian tubes. p53 protein accumulated and p27(Kip1) was down-regulated significantly in early-stage FTCs compared with normal Fallopian tubes. HER-2/neu overexpression was absent in normal Fallopian tubes and in all stage I FTCs (n = 6) but present in 57% (12/21) of advanced-stage FTCs. No differences in expression between grade 2 and 3 tumours were detected. HER-2 gain/amplification was found by array comparative genomic hybridization in 23% (3/13) of analysed FTCs and all showed overexpression. HER-2/neu overexpression also occurred without DNA copy number changes in three other cases. For p27(Kip1), expression and DNA copy number were unrelated.

CONCLUSIONS

p53 accumulation and p27(Kip1) down-regulation seem to be early events in Fallopian tube carcinogenesis. HER-2/neu showed overexpression, caused by gain/amplification in 50%, and may be involved in progression of FTC. These data contribute to a better understanding of the molecular carcinogenesis of FTC and to possible new therapeutic approaches.

An exploratory analysis of HER-2 amplification and overexpression in advanced endometrial carcinoma: a Gynecologic Oncology Group study

OBJECTIVES

To investigate the frequency and potential prognostic or predictive value of HER-2 amplification or overexpression in advanced and recurrent endometrial cancers.

METHODS

Immunohistochemical staining (IHC; DAKO Herceptest) and fluorescence in situ hybridization (FISH; Vysis Inc. PathVysion DNA Probe Kit) were performed on specimens collected on a randomized Gynecologic Oncology Group (GOG) protocol testing the addition of paclitaxel to doxorubicin/cisplatin.

RESULTS

HER-2 overexpression (either 2+ (moderate) or 3+ (strong) immunostaining) and HER-2 gene amplification (a ratio of HER-2 copies to chromosome 17 (CEP17) copies > or = 2) were detected in 44% (104 of 234; 58 were 2+ and 46 were 3+) and 12% (21 of 182) of specimens, respectively. There was a significant increased frequency of overexpression in serous tumors vs. all others (23 of 38, 61% vs. 81 of 196, 41%, respectively, P=0.03). HER-2 amplification also appeared to be more common in serous tumors, but results were not significant (6 of 28, 21% vs. 15 of 141, 11%, P=0.12). There was a significant association between grade and HER-2 amplification among nonserous tumors, with grades 1, 2, and 3 cancers demonstrating 3%, 2%, and 21% amplification, respectively (P=0.003). Neither overexpression nor amplification predicted overall survival (OS) after adjusting for treatment and performance status.

CONCLUSIONS

HER-2 amplification was more common in high grade tumors with a trend to being more common in serous tumors. There was no clear evidence for a survival difference or a difference in benefit from the addition of paclitaxel for women with HER-2 amplified or overexpressed tumors; however, power to detect clinically meaningful differences was low.

Hormone therapy in advanced and recurrent endometrial cancer: a systematic review

Endometrial cancer is a hormone-dependent malignancy, and the majority has a precursor phase of endometrial hyperplasia. Histologic subtypes have been recognized with differing natural history. The relationship between hormone response, histology, and molecular profile is not established, but the relevant biology is summarized. This study was a systematic review of the literature to identify which populations should be considered for hormone interventions. Systematic searches were carried out in the English literature for randomized controlled trials and phase II studies of hormone interventions in endometrial cancer. Five randomized trials and 29 phase II studies were identified comprising a total of 2471 patients. In previously untreated patients with grade 1 (G1) or G2 tumors, the response rate for progestogens and the progression-free survival is in the range of 11–56% and 2.5–14 months, respectively. Higher response rates are seen in progesterone receptor–positive cases. Phase II studies comprise the majority of the data and many are of poor quality. There was considerable heterogeneity in patient selection, prior treatment, and type of regimen, and meta-analysis was not possible. G3 or G4 toxicity was less than 5%. We conclude that hormone receptor assessments should be carried out in all patients entered on clinical trials and may aid clinical management in selected cases. Receptor-negative status should not be an absolute contraindication to hormone intervention. Integration of hormone treatment with conventional chemotherapy and growth factor–targeted therapy needs to be explored.

Small primary adenocarcinoma in adenomyosis with nodal metastasis: a case report

Background

Malignant transformation of adenomyosis is a very rare event. Only about 30 cases of this occurrence have been documented till now.

Case presentation

The patient was a 57-year-old woman with a slightly enlarged uterus, who underwent total hysterectomy and unilateral adnexectomy. On gross inspection, the uterine wall displayed a single nodule measuring 5 cm and several small gelatinous lesions. Microscopic examination revealed a common leiomyoma and multiple adenomyotic foci. A few of these glands were transformed into a moderately differentiated adenocarcinoma. The endometrium was completely examined and tumor free. The carcinoma was, therefore, considered to be an endometrioid adenocarcinoma arising from adenomyosis. Four months later, an ultrasound scan revealed enlarged pelvic lymph nodes: a cytological diagnosis of metastatic adenocarcinoma was made.

Immunohistochemical studies showed an enhanced positivity of the tumor site together with the neighbouring adenomyotic foci for estrogen receptors, aromatase, p53 and COX-2 expression when compared to the distant adenomyotic glands and the endometrium. We therefore postulate that the neoplastic transformation of adenomyosis implies an early carcinogenic event involving p53 and COX-2; further tumor growth is sustained by an autocrine-paracrine loop, based on a modulation of hormone receptors as well as aromatase and COX-2 local expression.

Conclusion

Adenocarcinoma in adenomyosis may be affected by local hormonal influence and, despite its small size, may metastasize.

Outcomes in surgical stage I uterine papillary serous carcinoma

OBJECTIVE

The optimal management of patients with stage I uterine papillary serous carcinoma (UPSC) is unclear. We sought to determine whether outcomes of women with surgical stage I UPSC differ with and without adjuvant therapy.

METHODS

Retrospective multi-institution analysis of women with stage I UPSC surgically staged from 1976 to 2006.

INCLUSION CRITERIA

comprehensive staging procedure including hysterectomy, bilateral salpingo-oophorectomy, selective pelvic/aortic lymphadenectomy, peritoneal cytology. Recurrence and survival were analyzed using Kaplan-Meier method.

RESULTS

Of 83 women with stage I UPSC, 36 (43%) received adjuvant therapies (23% radiotherapy, 3% chemotherapy, 15% chemotherapy and radiotherapy, 2% progestins). Three-year overall (OS) and progression-free survival (PFS) were 80% and 68%, respectively. Three-year OS and PFS by adjuvant treatment were observation (N=47) 86% and 78%, radiotherapy (N=17) 63% and 44%, chemotherapy with or without radiotherapy (N=17) 92% and 76%, respectively. Of the 18 recurrences, 9 (50%) included an extrapelvic component. Local recurrence was 2/30 (7%) following adjuvant radiotherapy and 7/53 (13%) without radiotherapy (p=0.48). Recurrence was higher in stage IB/IC (15/51, 29%) compared to stage IA (3/32, 9%). There has been one recurrence (5%) among the 22 women observed with stage IA disease.

CONCLUSION

In this largest reported series of women with surgical stage I UPSC, the high recurrence (29%) among patients with stage IB/IC disease highlights the need for clinical trials to test new therapeutic approaches. Surgically staged patients with IA disease had good prognosis. These data suggest that radiotherapy alone is not effective, that systemic therapy is needed, and that observation could be considered in patients with stage IA disease.

The oncogene HER2: its signaling and transforming functions and its role in human cancer pathogenesis

The year 2007 marks exactly two decades since Human Epidermal Growth Factor Receptor-2 (HER2) was functionally implicated in the pathogenesis of human breast cancer. This finding established the HER2 oncogene hypothesis for the development of some human cancers. The subsequent two decades have brought about an explosion of information about the biology of HER2 and the HER family. An abundance of experimental evidence now solidly supports the HER2 oncogene hypothesis and etiologically links amplification of the HER2 gene locus with human cancer pathogenesis. The molecular mechanisms underlying HER2 tumorigenesis appear to be complex and a unified mechanistic model of HER2-induced transformation has not emerged. Numerous hypotheses implicating diverse transforming pathways have been proposed and are individually supported by experimental models and HER2 may indeed induce cell transformation through multiple mechanisms. Here I review the evidence supporting the oncogenic function of HER2, the mechanisms that are felt to mediate its oncogenic functions, and the evidence that links the experimental evidence with human cancer pathogenesis.

Molecular targets in gynaecological cancers

The application of high throughput expression profiling and other advanced molecular biology laboratory techniques has revolutionised the management of cancers and is gaining attention in the field of gynaecological cancers. Such new approaches may help to improve our understanding of carcinogenesis and facilitate screening and early detection of gynaecological cancers and their precursors. Individualised prediction of patients' responses to therapy and design of personalised molecular targeted therapy is also possible. The studies of various molecular targets involved in the various signal pathways related to carcinogenesis are particularly relevant to such applications. At the moment, the application of detection and genotyping of human papillomavirus in management of cervical cancer is one of the most well established appliances of molecular targets in gynaecological cancers. Methylation, telomerase and clonality studies are also potentially useful, especially in assisting diagnosis of difficult clinical scenarios. This post-genomic era of clinical medicine will continue to make a significant impact in routine pathology practice. The contribution of pathologists is indispensable in analysis involving tissue microarray. On the other hand, both pathologists and bedside clinicians should be aware of the limitation of these molecular targets. Interpretation must be integrated with clinical and histopathological context to avoid misleading judgement. The importance of quality assurance of all such molecular techniques and their ethical implications cannot be over-emphasised.

Dual inhibition of ErbB1 (EGFR/HER1) and ErbB2 (HER2/neu)

Targeting of epidermal growth factor receptor (EGFR) and HER2 is a proven anti-cancer strategy. However, heterodimerisation, compensatory 'crosstalk' and redundancy exist in the ErbB network, and there is therefore a sound scientific rationale for dual inhibition of EGFR and HER2. Trials of approved agents in combination, for example trastuzumab and cetuximab, are underway. There is also a new generation of small molecule tyrosine kinase inhibitors (TKIs) and monoclonal antibodies (mABs) that target two or more ErbB receptors. Lapatinib, a TKI of EGFR and HER2, has shown clinical benefit in trastuzumab refractory breast cancer and is poised for FDA approval. Other agents include BIBW-2992 and HKI-272, irreversible TKIs of EGFR and HER2, and pertuzumab, a heterodimerisation inhibitor of EGFR and HER2.

Effect of ATM, CHEK2 and ERBB2 TAGSNPs and haplotypes on endometrial cancer risk

Family history of endometrial cancer increases the risk of developing the disease, but it is still largely unknown which germ-line genetic factors are involved in the aetiology of endometrial cancer. In a Swedish population-based case-control study including 705 cases and 1565 controls, we examined common variation in the ATM, CHEK2 and ERBB2 genes in relation to endometrial cancer risk overall, restricted to tumours of certain characteristics or stratified by various endometrial cancer risk factors. We genotyped a large number of single-nucleotide polymorphisms (SNPs) in the genes and selected seven haplotype-tagging SNPs (tagSNPs) in ATM, six tagSNPs in CHEK2 and seven tagSNPs in ERBB2 that could predict common variants and haplotypes (frequency > or =0.03) in each gene with R(2) > or = 0.8. We included the tagSNPs or their haplotypes as explanatory variables in unconditional logistic regression models adjusted for age. Our results indicated an increased risk of developing endometroid endometrial cancer for homozygous carriers of the rare allele (AA) of a tagSNP (rs4987886) in CHEK2 (P = 0.005) when contrasted with GG carriers. We also found a decreased endometrial cancer risk among non-smoking carriers of a haplotype in ATM (P = 0.0007) and among carriers of a haplotype in CHEK2, who had experienced menopause below 49 years of age (P = 0.0009) compared with non-carriers of these haplotypes. We found no effect of genetic variation in ERBB2 on endometrial cancer risk. In conclusion, it is possible that common variants in the ATM and CHEK2 genes, in interaction with oestrogen-related exposures, are involved in endometrial cancer aetiology.

The 17q12-q21 amplicon: Her2 and topoisomerase-IIalpha and their importance to the biology of solid tumours

Her2 and topoisomerase-IIalpha (T2A) gene amplification are separate events, although the latter is more frequently seen in Her2 amplified (34-90%) than in Her2 non-amplified (5-10%) tumours. There is a better correlation between Her2 amplification and protein overexpression in breast cancer (BC) than in other tumour types. This marker is also considered a powerful prognostic factor in BC, with similar data emerging in other solid tumours such as bladder, ovarian, endometrial, gastro-oesophageal and non-small cell lung cancer. Her2 amplification and/or overexpression are highly predictive of response to HER2-targeted compounds such as trastuzumab and lapatinib but have been inconsistent predictors of response to cytotoxic chemotherapy. There is also evidence that these tumours are relatively resistant to anti-oestrogen therapy (tamoxifen) but not to oestrogen deprivation (e.g. with aromatase inhibitors). T2A aberrations are uncommon events in solid tumours, with an overall prevalence of approximately 10%. T2A amplification has shown inconsistent correlation with T2A protein expression in preclinical and clinical studies, mainly because non-genetic events such as proliferation rate can also affect protein expression. Expression of T2A protein has not been shown to reliably predict response to T2A inhibitors, despite the fact that this enzyme is the direct target for these compounds. In BC, T2A amplification appears to be a good predictor of response to anthracyclines, but these data are still in the process of validation. The significance of T2A deletions is currently under investigation, but contrary to what was previously thought, it may also predict benefit from treatment with T2A inhibitors. The prognostic significance of T2A aberrations is currently unknown.

Specificity, selection and significance of gene amplifications in cancer

DNA copy number amplifications activate oncogenes and are found in the majority of advanced solid tumors. Cell-lineage specificity and oncogene affinity of DNA amplifications in cancer suggest that properties of precursor stem cells and selection pressure in the tissue micro-environment determine the genomic location of gene amplifications. Biological specificity and significance of gene amplifications make them potential targets for clinical applications. Here we discuss the specificity of non-randomly occurring DNA copy number amplifications as defining features for cancers, their selection in the tumor tissue, and significance in the clinical practice.