Karyotypic findings in tumors of the vulva and vagina

Vulval extra-mammary Paget's disease: the master of disguise revealed

Extra-mammary Paget's disease is a rare cancer affecting the anogenital region and can present with a myriad of symptoms. In women, the diagnosis of Paget's disease can be challenging as it mimics several other vulval conditions. It is important to promptly recognise this disease because of its potential association with synchronous tumours, such as colorectal adenocarcinoma. The mainstay of treatment is with immunomodulating therapies or surgery, but unfortunately the risk of recurrence is high and appears to be independent of treatment choice and tissue margin status. There is growing evidence to move away from traditional surgical excision to using topical therapy, such as imiquimod, as surgery can often be extensive and disfiguring with a prolonged recovery time. There is considerable psychosexual and physical morbidity associated with Paget's disease, largely owing to multiple surgical recurrences. As recurrences can occur several years after the initial presentation, long-term follow up of patients is recommended.

Reviewing vulvar Paget's disease molecular bases. Looking forward to personalized target therapies: a matter of CHANGE

OBJECTIVES

To review the published literature on vulvar Paget's disease (VPD) molecular bases, aiming to support the need for tailored treatment in women affected by this 'orphan' tumor.

METHODS

MEDLINE-PubMed and Scopus were interrogated using the following algorithm: (extramammary OR extra mammary OR vulvar) AND (paget OR pagets OR paget's) AND (molecular OR biological OR marker OR protein OR target OR expression). The inclusion criteria for papers were: peer-reviewed English-language journals, articles published in the last 30 years, studies focused on fixed research questions, quality assessment on the basis of the relevance and contribution to the selected topics.

RESULTS

A total of 42 studies were selected, providing the following results. Molecular markers implicated in cell cycle transitions seem to be related to prognosis and could help to tailor conventional treatments. Fragmented but consistent preliminary data exist on hormonal receptor expression, ERBB2 amplification/overexpression and abnormal vascular proliferation, offering a concrete possibility for target therapy trials. Conversely, other fields linked to the possible use of immunotherapy are currently relatively unexplored, such as the tumor 'immune contexture', programmed death ligand-1 (PD-L1) expression and defects in the mismatch repair system, which is involved in genomic instability and potentially promotes a consistent response to treatment.

CONCLUSIONS

Additional effort is needed to further characterize these aspects. Centralization of patients in dedicated units would be beneficial for concentrating patient numbers, collecting valuable clinical data and conducting clinical trials. Interdisciplinary study platforms should be developed and integrated into wider multicentric networks.

Expressions of miR-30c and let-7a are inversely correlated with HMGA2 expression in squamous cell carcinoma of the vulva

Malignant tumors of the vulva, most of them squamous cell carcinomas, account for only 5% of cancers of the female genital tract. Though little is known about the genetic features of these tumors, the Fragile Histidine Triad (FHIT) and High Mobility Group AT-hook 2 (HMGA2) genes were found deregulated. We wanted to gain more knowledge about the expression of HMGA2-related miRNAs such as miR-30c and let-7a, and whether a correlation exists between the expression of FHIT and HMGA2, in this tumor type. An inverse correlation was found in-as-much as HMGA2 was highly expressed (mean fold change 8.8) whereas miR30c and let-7a were both downregulated (mean fold change -3.9 and -2.3, respectively). The consistent overexpression of HMGA2 found in all tumors adds to the likelihood that this gene is of importance in SCC pathogenesis. Moreover, we came to the conclusion that miRNAs may be the cause of the deregulation of HMGA2. Our results also show that SCC of the vulva presents a characteristic molecular pattern with FHIT being downregulated whereas HMGA2 is upregulated.

Recurrent fusion transcripts in squamous cell carcinomas of the vulva

Juxtaposition of two different genes or gene parts due to chromosomal rearrangement is a well-known neoplasia-associated pathogenetic mechanism. The detection and characterization of such tumorigenic fusions is of great importance both research-wise, diagnostically because they may be specific for distinct tumor entities, and because they may serve as therapeutic targets for antioncogenic drugs that interact directly with the molecular changes responsible for neoplastic transformation.

At present, more than 10,000 fusion transcripts have been reported in different types of neoplasia, with one tenth of them being identified in squamous cell carcinomas (SCC) of different locations. No recurrent fusion gene has to date been identified in SCC of the vulva.

We performed high-throughput paired-end RNA-sequencing of 12 vulvar SCC and found two recurrent fusions with the STIP1-CREB3L1 and ZDHHC5-GPR137 being present in two tumors each. The transcripts were detected only in the tumor samples, not in normal vulvar tissue from healthy donors used as control. The CREB3L1 and ZDHHC5 genes encode proteins involved in transcription suggesting that the chimeras may alter downstream events in their respective pathways. Expression analysis of the CREB3L1 gene showed the presence of two distinct groups of tumors, one having fusion and downregulation of the gene and the other showing upregulation of CREB3L1.

HMGA2 expression pattern and TERT mutations in tumors of the vulva

Malignant tumors of the vulva account for only 5% of cancers of the female genital tract in the USA. The most frequent cancers of the vulva are squamous cell carcinoma (SCC) and malignant melanoma (MM). Little is known about the genetic aberrations carried by these tumors. We report a detailed study of 25 vulva tumors [22 SCC, 2 MM, 1 atypical squamous cell hyperplasia (AH)] analyzed for expression of the high-mobility group AT-hook family member genes HMGA2 and HMGA1, for mutations in the IDH1, IDH2 and TERT genes, and for methylation of the MGMT promoter. The RT-PCR and immunohistochemistry analyses showed that HMGA2 was expressed in the great majority of analyzed samples (20 out of 24; SCC as well as MM) but not in the normal controls. HMGA1, on the other hand, was expressed in both tumors and normal tissues. Five of the 24 tumors (all SCC) showed the C228T mutation in the TERT promoter. Our results showed that HMGA2 and TERT may be of importance in the genesis and/or the progression of tumors of the vulva.

Genomic aberration patterns and expression profiles of squamous cell carcinomas of the vulva

Little is known about the genomic abnormalities of squamous cell carcinomas (SCC) of the vulva and how they correlate with gene expression. We determined the genomic and expression profiles of 15 such SCC using karyotyping, DNA ploidy analysis, arrayCGH, and expression arrays. Four of the five cases with clonal chromosomal aberrations found by G-banding showed highly abnormal karyotypes with multiple rearrangements. The imbalances scored by arrayCGH mapped to different chromosomes with losses being more common than gains. Frequent losses were scored from 3p and 8p whereas gains were frequent from 3q and 8q (loss of 8p with concomitant gain of 8q mostly occurred via 8q isochromosome formation). This is the first study of vulvar tumors using arrayCGH, and some frequent imbalances could be defined precisely. Of particular note were the sometimes large, sometimes small deletions of 3p and 9p which had minute areas in 3p14 and 9p23 as minimal commonly deleted regions. FHIT (3p14) and PTPRD (9p23) are the only genes here. They were both lost in seven cases, including homozygous losses of PTPRD in four tumors. Using qPCR we could demonstrate deregulation of the FHIT gene in tumor cells. Hence, this gene is likely to play a pathogenetic role in vulvar SCC tumorigenesis. Expression array analyses also identified a number of other genes whose expression profile was altered. Notable among the downregulated genes were MAL (in 2q11), KRT4 (in 12q13), and OLFM4 (in 13q14), whereas upregulated genes included SPRR2G (in 1q21.3) and S100A7A (in 1q21.3).

Extramammary Paget's disease of the vulva: An annotated review of the current literature

Extramammary Paget's disease is a rare and unusual neoplastic entity that presents mainly on apocrine gland-bearing skin. The vulva is the most common site of involvement but any area of the anogenital skin can be affected. Due to its rarity, variable clinical course and deceptive histological appearance it has a high misdiagnosis rate and both gynaecologists and dermatologists have limited experience in its management. The significance of the disease lies in its association with underlying malignancy as well as its inherent ability to invade the dermis and metastasise. The management is notoriously complicated and recurrence rates are high despite aggressive surgeries. Several alternative modalities are being explored, with results that are often variable and unpredictable. This review summarises the histopathological, clinical and therapeutic features of extramammary Paget's disease of the vulva reported in recent years.

Characterization of 10 vulvar carcinoma cell lines by karyotyping, comparative genomic hybridization and flow cytometry

OBJECTIVE AND METHODS

Ten vulvar squamous cell carcinoma cell lines established at the University of Michigan (UM-SCV-1A, -1B, -2, -3, -4, -6, -7) and at the University of Turku (UT-SCV-1, -2, -3) were characterized by G-banding karyotyping, comparative genomic hybridization (CGH), and deoxyribonucleic acid (DNA) flow cytometry.

RESULTS

All cell lines had hyperdiploid DNA content as measured by flow cytometry. The DNA index (DI) remained relatively stable through different passages in 9 of 10 cases. DIs of UM-SCV-3 and UT-SCV-2 were near-diploid, as were the corresponding karyotypes. The 10 SCVs showed remarkable genetic similarities with respect to consistent chromosome rearrangements. Loss of 3p, noted in 8/10 SCVs, was narrowed to the smallest common region at 3p11-3p13. Loss of 8pter-p11 was observed in 10/10 cell lines. Loss of 11qter-q23 was present in UM-SCV-1 and -2, and in all four recently karyotyped SCVs. Other consistent losses include Xpter-p11 in 6/10, and 18qter-q11 in 7/10 cell lines. Common gains included gain of 8q in 8/10 and 3q in 6/10. Consistent copy number imbalances were confirmed by CGH; concerning loss of 3p, in 63%, to loss of 8p in 70%, to gain of 3q in 83%, and to gain of 8q in 75% of the cell lines.

CONCLUSIONS

CGH and karyotyping showed concordance in defining copy number imbalances, thus supporting the accuracy of CGH to detect chromosome imbalances in tumors that cannot be karyotyped.

Extramammary Paget disease of the scrotum with features of Bowen disease

The scrotum is an uncommon site for the presentation of extramammary Paget disease (EMPD). We describe a case of EMPD that was discovered in a patient who had been previously diagnosed and treated for squamous cell carcinoma in situ of the scrotum 3 years earlier. Pathologic examination of the current scrotectomy specimen revealed an erythematous patch with areas of pale induration. Microscopic examination revealed areas with the characteristic histology of Paget disease adjacent to areas characteristic of Bowen disease. Immunohistochemical findings demonstrated a strong expression of carcinoembryonic antigen, cytokeratin 7, and low-molecular-weight cytokeratins (CAM 5.2) in both of these areas, giving support to the overall diagnosis of EMPD. High-molecular-weight cytokeratins (34betaE12) were uncharacteristically expressed in the cytoplasm of the Paget cells with equal or greater strength than in the surrounding keratinocytes, suggesting some degree of squamous differentiation. Very few publications have reported the coexistence of EMPD with squamous cell carcinoma in situ, occurring mostly in the vulva. To our knowledge, our case is the first report of scrotal EMPD with features of Bowen disease. Our findings support the theory that primary EMPD arises multifocally from multipotential epidermal cells.

Cytogenetic characterization of tumors of the vulva and vagina

Neoplasms of the vulva and vagina account for less than 5% of all female genital tract cancers. Squamous cell carcinoma (SCC) represents more than 70% of the cases in both locales, followed by melanoma, basal cell carcinoma, Paget's disease, and other carcinoma subtypes. Until recently, only few cases had been analyzed by chromosome banding techniques and karyotyped, and also the number subjected to molecular cytogenetic analysis remains low. To understand better the genetic changes harbored by the neoplastic cells in cancer of the vulva and vagina, we analyzed cytogenetically 51 such tumors, finding karyotypic abnormalities in 37. All tumors were analyzed by G-banding, sometimes supplemented by multicolor fluorescence in situ hybridization, and a subset of tumors was also analyzed by comparative genomic hybridization. The two cytogenetically abnormal cases of Paget's disease both had two clones, one with gain of chromosome 7 as the sole change, the other with loss of the X chromosome among, in one case, other aberrations. The four cytogenetically abnormal malignant melanomas (three of the vulva, one of the vagina) presented complex karyotypes with aberrations involving different chromosomes but most often chromosome 1, specifically 1p12-q41. In the 31 cytogenetically abnormal SCCs, different clonal karyotypic abnormalities were seen. Intratumor heterogeneity with multiple clones was observed in 11 cases. The clones were cytogenetically unrelated in eight tumors but related in three, indicating that in the latter clonal evolution had taken place from a single malignantly transformed cell. The main chromosomal imbalances were gains of, or from, chromosome arms 3q, 5p, 8q, 9q, and 19q, and loss from 11q. Breakpoint clusters were seen in 11q13-23, 2q22-35, and 19q13, as well as in the centromeres and pericentromeric bands of chromosomes 3, 8, 9, 13, 14, and 22.

HER2 oncogene amplification in extramammary Paget's disease

AIMS

To study HER2 oncogene amplification and over-expression in skin samples of 23 patients with extramammary Paget's disease (EMP). EMP is a rare intra-epidermal adenocarcinoma, which has been reported to over-express the HER2 oncoprotein.

METHODS AND RESULTS

HER2 gene amplification, detected by chromogenic in-situ hybridization, was found in 43% (10/23) of the lesions. HER2 protein over-expression (3+ immunostaining intensity) was found in 12 tumours (52%), including all 10 tumours with gene amplification. Two tumours showed low-level (2+) HER2 immunostaining. Mammary Paget's lesions, which were used as controls, showed HER2 amplification and over-expression in all 10 cases studied.

CONCLUSIONS

These results indicate that HER-2 protein over-expression in EMP is common and due exclusively to gene amplification. They open up the possibility of HER2-targetted immunotherapy for patients with HER2+ disease.

Loss in 3p and 4p and gain of 3q are concomitant aberrations in squamous cell carcinoma of the vulva

Neoplasm of the vulva is a rare malignancy accounting for <5% of all female genital-tract cancer. However, in recent years the incidence of vulva intraepithelial neoplasia, known to serve as a precursor to carcinoma, has increased in young women generating considerable interest in its pathogenesis. Genetic changes at the molecular level in precursor or invasive vulvar tumors are not well investigated, and DNA copy number changes have not been reported until now. We used comparative genomic hybridization (CGH) to analyze genetic alterations in 10 primary invasive squamous cell carcinomas of the vulva. Chromosomal aberrations were identified in 8/10 cases. The most frequent chromosomal losses were 4p13-pter (five cases), 3p (four cases), and 5q (two cases), and less frequent losses were detected at 6q, 11q, and 13q (one case each). The most frequent chromosomal gains were 3q (four cases) and 8p (three cases), and less frequent gains were found in 9p, 14, 17, and 20q (one case each). The pattern of chromosomal imbalance in vulvar cancer detected by CGH was revealed to be very similar to that in cervical cancers, despite regional differences in their prevalence. These results suggest that the pathogenic pathways in vulvar and cervical carcinomas may be similar and that the genetic background may be common to these two squamous cell carcinomas.

Chromosome 17 aneusomy detected by fluorescence in situ hybridization in vulvar squamous cell carcinomas and synchronous vulvar skin

Vulvar squamous cell carcinoma (SCC) affects a spectrum of women with granulomatous vulvar diseases, human papillomavirus (HPV) infections, and chronic inflammatory vulvar dermatoses. To determine whether there is evidence of chromosomal instability occurring in synchronous skin surrounding vulvar SCCs, we investigated abnormalities in chromosome 17 copy number. Samples of SCC, vulvar intraepithelial neoplasia (VIN), and surrounding vulvar skin were obtained from all vulvar excisions performed for squamous neoplasia at Albany Medical College from 1996 to 1997. Histological categorization, fluorescent in situ hybridization (FISH) for the alpha satellite region of chromosome 17, DNA content by image analysis, and Ki-67 labeling were evaluated. Controls of normal vulvar skin not associated with cancer were used for comparison. One hundred ten specimens were obtained from 33 patients with either SCC or VIN 3 and consisted of 49 neoplastic, 52 nonneoplastic, and 9 histologically normal vulvar skin samples. The majority of SCCs (88%) and a minority (18%) of VIN 3 excisions were associated with lichen sclerosus. Normal vulvar skin controls did not exhibit chromosome 17 polysomy (cells with more than four FISH signals), whereas 56% of normal vulvar skin associated with cancer did. Moreover, the frequency of polysomy significantly increased as the histological classification progressed from normal to inflammatory to neoplastic lesions. The largest mean value and variance for chromosome 17 copy number was identified in SCCs (2.4 +/- 1.0) with intermediate values identified, in decreasing order, for SCC in situ (2.1 +/- 1.0), VIN 2 (2.1 +/- 0.8), lichen sclerosus (2.0 +/- 0.5), lichen simplex chronicus (1.9 +/- 0.4), and normal skin associated with SCC (1.8 +/- 0.4) compared with control vulvar skin (1.5 +/- 0. 05). Concordance of chromosome 17 aneusomy between cancers and synchronous skin lesions was found in 48% of patients. Loss of chromosome 17 was identified 5% of all samples and was significantly associated with women with SCC in situ (HPV-related). Both DNA content and Ki-67 labeling positively and significantly correlated with mean chromosome 17 copy number (r = 0.1, P: = 0.007). A high degree of genetic instability (aneuploidy) occurs in the skin surrounding vulvar carcinomas. As these events could be detected in histologically normal skin and inflammatory lesions (lichen sclerosus), chromosomal abnormalities may be a driving force in the early stages of carcinogenesis. Differences in chromosomal patterns (loss or gain) support the concept of at least two pathways in vulvar carcinogenesis.