Epigenetic Regulation of Driver Genes in Testicular Tumorigenesis.

In testicular germ cell tumor type II (TGCT), a seminoma subtype expresses an induced pluripotent stem cell (iPSC) panel with four upregulated genes, OCT4/POU5F1, SOX17, KLF4, and MYC, and embryonal carcinoma (EC) has four upregulated genes, OCT4/POU5F1, SOX2, LIN28, and NANOG. The EC panel can reprogram cells into iPSC, and both iPSC and EC can differentiate into teratoma. This review summarizes the literature on epigenetic regulation of the genes. Epigenetic mechanisms, such as methylations of cytosines on the DNA string and methylations and acetylations of histone 3 lysines, regulate expression of these driver genes between the TGCT subtypes. In TGCT, the driver genes contribute to well-known clinical characteristics and the driver genes are also important for aggressive subtypes of many other malignancies. In conclusion, epigenetic regulation of the driver genes are important for TGCT and for oncology in general.

Germ cell tumour growth patterns originating from clear cell carcinomas of the ovary and endometrium: a comparative immunohistochemical study favouring their origin from somatic stem cells.

AIMS: To report a series of 11 ovarian and one endometrial neoplasm in elderly patients with mixed clear cell tumour and germ cell tumour (GCT) components, to compare their immunohistochemical profiles and demonstrate a putative stem cell population. METHODS AND RESULTS: The clear cell tumours included 11 clear cell carcinomas (CCC) and one borderline clear cell tumour, while the GCT always included glandular yolk sac tumour (YST). In four cases, there were also foci of teratoma with immature neuroepithelial and endodermal tissues and undifferentiated areas showing true embryoids. To distinguish between the clear cell and YST components, the following antibodies were used: HNF1-ß, napsin-A, cytokeratin 7 (CK7), PAX8, EMA, AFP, SALL4, villin, glypican-3 (GPC-3), GATA3, HepPar-1, OCT4, CDX2, CD30 and SOX2. HNF1-ß, CK7, EMA and GPC-3 were often expressed in both components. Other markers had higher specificity for each cellular lineage; napsin-A and PAX8 were expressed only in CCC, while SALL4, villin, AFP and HepPar-1 were positive in the glandular YST component but negative in the clear cell component. OCT4 expression occurred in six of 10 cases and consistently in teratoma (four of four). CONCLUSIONS: There is considerable immunophenotypical overlap between the two components in these mixed neoplasms, and a panel of markers should be used to facilitate the distinction. We propose that OCT4-expressing somatic cancer cells differentiate into GCT and represent spontaneously induced pluripotent stem cells, possibly conditioned by age-related epigenetic factors. These neoplasms have features of prepubertal type GCT showing lack of 12p gain, preponderance of YST and coexistence with immature neuroectoderm. However, there may also be undifferentiated stem cell areas with embryoid bodies, of the type seen in postpubertal testicular GCT, but lacking a complete embryonal carcinoma immunophenotype.

Endometrial Changes in Surgical Specimens of Perimenopausal Patients Treated With Ulipristal Acetate for Uterine Leiomyomas.

Ulipristal acetate (UPA) is used to treat leiomyomas, and its effect on the endometrium has been studied in biopsy material. Reversible histologic modifications were found, named progesterone receptor modulators-associated endometrial changes (PAEC). However, hysterectomies from patients treated with UPA have not been analyzed. For the first time, we examined surgical specimens from 100 leiomyoma-treated patients for UPA-related endometrial changes. We analyzed the distribution of lesions, involution after treatment, and the relationship between type and extent of lesions and dosage. Clinically, 72 patients were treated with 1 cycle of UPA; 23 patients with 2 cycles, and 5 with 3 cycles. A total of 66 patients underwent surgery in the first 4 wk after treatment, 24 were operated between 5 and 12 wk after discontinuation of UPA, and 10 after more than 12 wk after the last cycle, up to a maximum of 32 wk. Histologically normal endometria were found in 41 cases and PAEC in 59 cases. PAEC consisted of irregular, cystic glands showing a flattened secretory-like epithelium with vacuolation, coexisting mitoses and apoptosis, and were found focally within cyclic endometria in 51 cases. Only in 8 cases did diffuse PAEC involve the whole endometrium, transforming it into a thick spongy cushion. PAEC also occurred in adenomyosis. There was no relationship between dosage and type and extent of lesions. Diffuse PAEC, which usually presents differential diagnoses with hyperplasia, occurred in only 8 cases, being only present during the first 4 wk after discontinuation of treatment and was independent of the number of cycles administered.

Pseudomyxoma-type Invasion in Gastrointestinal Adenocarcinomas of Endometrium and Cervix: A Report of 2 Cases.

This paper presents a clinicopathologic and immunohistochemical report of 2 gastrointestinal-type tumors, one in the endometrium and the other in the cervix. Both showed extensive invasion into the pelvic structures with acellular mucin, identical to pseudomyxoma but in the absence of appendiceal or ovarian tumors. Case 1 was an 81-yr-old female with a Stage III endometrial gastrointestinal-type adenocarcinoma who had had an endometrial polyp with intestinal metaplasia 4 years previously. Case 2 was a 68-yr-old female with Stage IIIB endocervical gastrointestinal-type adenocarcinoma. Both were associated with a pseudomyxoma type of invasion, which in the endometrial case was transmural through the myometrium, and in the cervical case involved parametria, pelvic floor, and lymph nodes. Immunohistochemically, both tumors had a gastrointestinal phenotype coexpressing cytokeratins 7 and 20, CDX2, villin, MUC2, MUC5AC, and MUC6 and were negative for human papillomavirus, analyzed by real-time polymerase chain reaction. The first case exemplifies intestinal endometrial metaplasia as a precursor lesion of the rare gastrointestinal type of adenocarcinoma and also proves its progression into carcinoma. The second case exemplifies the highly aggressive nature of cervical invasion forming mucin lakes. Extensive pseudomyxoma in the uterus and cervix was associated with high clinical stages with marked lymphovascular invasion and lymph node metastases.

The Impact on Survival of an Extensive Sex Cord-like Component in Mullerian Adenosarcomas: A Study Comprising 6 Cases.

Mullerian adenosarcomas are uncommon tumors of the female genital tract characterized by a synchronous proliferation of benign glands and sarcomatous stroma. In general, uterine Mullerian adenosarcomas are associated with a low risk of recurrence. The presence of "stromal overgrowth" (SO), historically defined by an estimate of the volume of sarcoma growing independently of epithelium, is associated with deep myometrial invasion, presence of heterologous elements, and poor outcomes. Very rarely, the stromal component can harbor foci resembling ovarian sex cord tumors (FROSCT). The aim of this study was to determine whether the presence of an extensive FROSCT component in Mullerian adenosarcomas has an impact on survival, akin to more typical types of SO. Six patients were included in this study. Age ranged from 39 to 71 yr. Five patients presented with uterine lesions (4 intracavitary, 1 isthmic), and 1 was located in the ovary. Tumors ranging in size from 2.5 to 19 cm were all diagnosed as Stage I. Morphologically, all had prominent FROSCT-like components that comprised 60% to 90% of tumor volume. Immunohistochemically, the FROSCT component was positive for CAM 5.2, vimentin, WT1, CD56, α-inhibin, calretinin, androgen and progesterone receptors, α-actin, and desmin. All patients are alive without disease at 26 to 102 mo. Compared with adenosarcomas with typical forms of SO, FROSCT overgrowth is low grade and not associated with recurrence or metastasis in this small series. Therefore, Mullerian adenosarcoma with extensive FROSCT should not be equated with SO.

Ovarian strumal carcinoid containing appendiceal-type mucinous tumor patterns presenting as pseudomyxoma peritonei.

We report for the first time a case of ovarian strumal carcinoid containing both trabecular carcinoid and mucinous glands lined by both goblet and neuroendocrine cells and a low-grade mucinous neoplasm that presented clinically as pseudomyxoma peritonei in the absence of appendiceal lesion in a 58-yr-old woman. Histologically, there were both a tall columnar cell epithelial component lacking neuroendocrine cells, showing the scalloped contours and subepithelial clefts of low-grade appendiceal-type neoplasms and a mixed goblet cell neuroendocrine element. Characteristically, both reproduced appendiceal neoplastic phenotypes in a teratoid fashion. In addition, we present previously unreported oncocytic and mucinous changes in the thyroideal components of strumal carcinoid. This case represents a rare instance of pseudomyxoma peritonei of primary ovarian origin and is an example of multiple somatic teratoid endodermal differentiations of the different sections of the embryonal gut: foregut represented by thyroid, midgut by both mucinous appendiceal components, and hindgut by trabecular carcinoid.

Lipomatous variant of angiomyofibroblastoma involving the vulva: report of 3 cases of an extremely rare neoplasm with discussion of the differential diagnosis.

We report 3 cases of the extremely rare lipomatous variant of angiomyofibroblastoma (AMF) involving the vulva of women aged 35, 45, and 47. The lesions ranged in size from 2.5 to 12 cm in maximum dimension and the largest had a gross "fatty" appearance. The percentage of adipose tissue was approximately 50% in 1 case and over 90% in the other 2. In all the cases, there was a background of typical AMF with bland spindled and epithelioid cells arranged around blood vessels, although in the cases with >90% adipose tissue, this was subtle and diffusely interspersed with the adipose tissue. In all the cases, the spindled and epithelioid cells were positive with estrogen receptor. Given the morphologic features, misdiagnosis as a lipomatous neoplasm is likely, especially in cases with a minor component of typical AMF. We review the literature on lipomatous AMF and discuss the differential diagnosis.

Papillary ependymoma of the endometrium.

AIMS: To report an exceptional case of papillary ependymoma occurring in the endometrium. METHODS AND RESULTS: A clinicopathological study was performed regarding a case of papillary ependymoma occurring in the endometrial cavity of a 61-year-old patient who had presented with a solid-type, stage III anaplastic ependymoma of the ovary, treated with cytoreductive surgery that included total abdominal hysterectomy. The uterus was enlarged and showed a dilated cavity, with broadly implanted papillary excrescences without myometrial invasion that were covered by tall, cylindrical cells. These cells had glial fibrillary acidic protein-expressing cytoplasm that was also positive for cytokeratins 7, 8, 18, and 34ß-E12, epithelial membrane antigen, S100 protein, vimentin, and oestrogen and progesterone receptors. CONCLUSIONS: Pathogenetically, the presence of this uterine ependymoma could represent either an example of multicentricity or a phenomenon of transtubal implantation of the ovarian tumour. Exceptionally, papillary ependymoma can occur in the endometrium, and may prompt differential diagnoses with other papillary endometrial tumours. Pathologists should consider this rare possibility in the differential diagnosis of papillary ovarian and endometrial lesions.

A diagnostic immunohistochemical panel for yolk sac (primitive endodermal) tumours based on an immunohistochemical comparison with the human yolk sac.

AIMS: To establish a diagnostic immunohistochemical panel for various histotypes of yolk sac (primitive endodermal) tumours (YSTs) by comparison with the human yolk sac (HYS) immunophenotype. METHODS AND RESULTS: Twenty-five YSTs showing either classical patterns (CPs) of histology (microcystic/reticular, n = 14; polyvesicular, n = 1; and hepatoid, n = 1) or somatic glandular patterns (SGPs; n = 9) were analysed for expression of α-fetoprotein (AFP), glypican-3 (GPC3), villin, hepatocyte paraffin-1 (HepPar-1), CDX2, SALL4 and LIN28. AFP expression was constantly heterogeneous in CPs but tended to be focal/absent in SGPs. GPC3 was diffuse in CPs but heterogeneous (seven cases) or focal/absent (two cases) in SGPs. HepPar-1 expression was focal in all but three cases (diffuse in one CP-hepatoid and two SGPs). CDX2 positivity was focal in CPs but heterogeneous (seven cases) or diffuse (two cases) in SGPs. Villin, SALL4 and LIN28 were diffusely positive in nearly all cases. CONCLUSIONS: CPs reproduce the immunophenotype of HYS and early endoderm with variable expression of both AFP and markers of early gut or hepatic differentiation. SGPs with intestinal differentiation often have incomplete immunophenotypes. A differential diagnosis panel, including both markers of pluripotentiality (SALL4 and/or LIN28) and endoderm (AFP, GPC3 and villin), is proposed. It identifies overlapping multidifferentiation of primitive and somatic immunophenotypes, supporting the recently proposed term of primitive endodermal tumours.

Reproducibility of current classifications of endometrial endometrioid glandular proliferations: further evidence supporting a simplified classification.

AIMS: To compare the reproducibility of the current (2003) World Health Organization (WHO), endometrial intraepithelial neoplasia (EIN) and European Working Group (EWG) classifications of endometrial endometrioid proliferations. METHODS AND RESULTS: Nine expert gynaecological pathologists from Europe and North America reviewed 198 endometrial biopsy/curettage specimens originally diagnosed as low-grade lesions. All observers were asked to classify the cases by using the categories described in each scheme: six for WHO, four for EIN, and three for EWG. The results were evaluated by kappa statistics for more than two observations. The analysis was repeated using only two major categories (benign versus atypical/carcinoma). Both the WHO and EIN classifications showed poor interobserver agreement (κ = 0.337 and κ = 0.419, respectively), whereas the EWG classification showed moderate agreement (κ = 0.530). Full agreement between pathologists occurred in only 28% for the WHO classification, 39% for the EIN classification, and 59% for the EWG classification. With only two diagnostic categories, kappa values increased in all classifications, but only the EWG classification reached a substantial level of agreement (κ = 0.621); similarly, full agreement among all pathologists increased to 70% for the WHO classification, 69% for the EIN classification, and 72% for the EWG classification. CONCLUSIONS: A two-tier classification of endometrial endometrioid proliferative lesions improves reproducibility, and should be considered for the diagnosis of endometrial biopsy/curettage specimens.

Coexistence of placental site nodule and cervical squamous carcinoma in a 72-year-old woman.

We report a unique case of the coexistence of cervical cancer and placental site nodule (PSN) in a 72-year-old multiparous woman presenting with vaginal bleeding. She had undergone tubal sterilization 30 years before. On admission, she had profuse vaginal bleeding, and a bulky cervical mass was seen on vaginal examination. Histology revealed the coexistence of a moderately differentiated invasive squamous cell carcinoma with a PSN in its stroma. Its immunohistochemistry revealed characteristic phenotypes for both lesions--the squamous carcinoma was strongly positive for p16. The intermediate trophoblasts of the PSN showed a diffuse positivity for CAM 5.2, human placental lactogen, CD10, and α-inhibin and, focally, for human chorionic gonadotropin. This is the first report on the coexistence of these 2 lesions in an elderly postmenopausal patient and demonstrates that PSN can be found after the menopause as an unexpected lesion in this age group, mimicking various cervical malignancies.

Yolk sac tumours revisited. A review of their many faces and names.

We review the current knowledge on human yolk sac tumours (YSTs) 50 years after their initial description. Their complex nomenclature and histogenesis stress the fact that they are not a discrete entity, but represent a multifaceted group of neoplasms, for which the term primitive endodermal tumours would be more appropriate, accounting for their capacity to differentiate into various extraembryonal and somatic cell types. Different histological patterns of human YSTs correlate with the developmental potential of primitive endoderm and mesenchyme, but they are also similar to some murine experimental tumours. Exceptionally, YSTs replicate the tubular structures of the human yolk sac and allantois. Endodermal somatic differentiation reproduces pulmonary, intestinal and hepatic tissues and are identical with some, embryonal-type endodermal, gastric and lung carcinomas, which are indistinguishable from YSTs. YSTs may show an overgrowth of their mesenchymal (sarcomatous) and epithelial components (such as mucinous carcinoma or carcinoid) and also be a source of haematological malignancies. YSTs associated with non-germ cell tumours probably originate from malignant pluripotent somatic stem cells. Only AFP and glypican-3 are characteristic immunohistochemical markers. Pluripotent antibodies (SALL4, Lin28, IMP-3) help in differential diagnoses, while some differentiation markers (CDX2, TTF-1, HepPar1) facilitate recognition of unusual variants of YSTs.

An analysis of five clear cell papillary cystadenomas of mesosalpinx and broad ligament: four associated with von Hippel-Lindau disease and one aggressive sporadic type.

AIMS: Clear cell papillary cystadenoma (CCPC) is associated with von Hippel-Lindau disease (VHLD), but rarely involves mesosalpinx and broad ligament (M/BL). This study provides new data about its behaviour and immunophenotype. METHODS AND RESULTS: We performed an analysis of four benign cases of CCPC of M/BL with either characteristic clinical features or genetic markers [loss of heterozygosity (LOH)] of VHLD in patients ranging from 24 to 36 years and a sporadic case in a 52-year-old presenting with peritoneal metastases. All CCPCs were papillary but had solid and tubular areas. Haemorrhage, thrombosis and scarring were constant features and related to an unusual pattern of sub-epithelial vascularity. All clear or oxyphilic cells co-expressed cytokeratin 7 (CK7), CAM5.2 and vimentin, with strong apical CD10 and nuclear paired box gene 2 (PAX2) immunoreactivity. Three cases also showed positivity for VHL40, epithelial membrane antigen (EMA), Wilms' tumour suppressor gene (WT-1) and cancer antigen 125 (CA125) but only one expressed renal cell carcinoma (RCC) antigen. Vascular plexus overexpressed nuclear and cytoplasmic WT-1. CONCLUSION: The VHLD-associated cases appeared to be benign, but the sporadic case exhibited a low malignant potential. CCPCs show histological and immunophenotypical similarities with the recently reported clear cell papillary RCC, although the previously unreported apical CD10 and nuclear PAX2 expression may be related to their mesonephric origin. CCPC has a distinctive sub-epithelial vascular pattern that is consistent with its pathogenesis.

Embryonal (botryoides) rhabdomyosarcoma of the uterus harboring a primitive neuroectodermal tumor component.

The association of a uterine sarcoma botryoides of the adolescence with a primitive neuroectodermal tumor is reported in a 12-year-old patient who presented with abnormal vaginal bleeding that occurred after passing per vaginam a polypoid mass. The sarcoma botryoides of the adolescence exhibited foci of cartilage and a central area of primitive neuroectodermal tumor with a trabecular, adamantiform histology and prominent angiogenesis. Primitive neuroectodermal tumor was positive for vimentin, synaptophysin, neuron-specific enolase, CD99, and SOX2 and negative for both the FLI-1 fusion protein and the rearrangement of ESWR1 gene. The neoplasm exhibited a nonaggressive behavior similar to sarcoma botryoides of the adolescence, being alive and well 3 y after its presentation. This is possibly related to its polypoid nature and the absence of invasive features at its uterine insertion level. A conservative approach without further resection and chemotherapy was indicated taking into account the patient's age.

Tyrosine kinase receptor status in endometrial stromal sarcoma: an immunohistochemical and genetic-molecular analysis.

Endometrial stromal sarcomas (ESS) are rare uterine malignant mesenchymal neoplasms, which are currently treated by surgery, as effective adjuvant therapies have not yet been established. Tyrosine kinase inhibitors have rarely been applied in ESS therapy, with few reports describing imatinib responsivity. The aim of this study was to analyze the status of different tyrosine kinase receptors in an ESS series, in order to evaluate their potential role as molecular targets. Immunohistochemistry was performed for EGFR, c-KIT, PDGFR-α, PDGFR-ß, and ABL on 28 ESS. EGFR, PDGFR-α, and PDGFR-ß gene expression was investigated by real-time polymerase chain reaction (qRT-PCR) on selected cases. "Hot-spot" mutations were screened for on EGFR, c-KIT, PDGFR-α, and PDGFR-ß genes, by sequencing. All analysis was executed from formalin-fixed, paraffin-embedded specimens. Immunohistochemical overexpression of 2 or more tyrosine kinase receptors was observed in 18 of 28 tumors (64%), whereas only 5 tumors were consistently negative. Gene expression profiles were concordant with immunohistochemical overexpression in only 1 tumor, which displayed both high mRNA levels and specific immunoreactivity for PDGFR-α, and PDGFR-ß. No activating mutations were found on the tumors included in the study. This study confirms that TKRs expression is frequently observed in ESS. Considering that the responsiveness to tyrosine kinase inhibitors is known to be related to the presence of specific activating mutations or gene over-expression, which are not detectable in ESS, TKRs immunohistochemical over-expression alone should not be considered as a reliable marker for targeted therapies in ESS. Specific post-translational abnormalities, responsible for activation of TKRs, should be further investigated.

Endometrial intestinal metaplasia: a report of two cases, including one associated with cervical intestinal and pyloric metaplasia.

Intestinal metaplasia of the endometrium is extremely uncommon with only a single earlier case report. We describe 2 cases of endometrial intestinal metaplasia, one of them involving an endometrial polyp, characterized by the presence of intestinal-type epithelium containing goblet and neuroendocrine cells, which were positive with CK20, CDX2, chromogranin, and villin. In 1 case, there was concomitant intestinal and pyloric metaplasia in the endocervix. Together with the observation of the earlier reported case of endometrial intestinal metaplasia, there was also intestinal metaplasia in the cervix. This suggests a possible association between intestinal metaplasia at different sites in the female genital tract.

Florid, papillary endosalpingiosis of the axillary lymph nodes.

A 55-year-old woman underwent radical mastectomy and axillary node dissection because of an invasive ductal carcinoma with neuroendocrine features. Histologically, all 22 sampled lymph nodes had widespread cystic inclusions lined by a regular, serous-type epithelium positive for cytokeratin-7, WT-1, CA125, and estrogen receptors. Papillary projections were found in the lumen of some cysts. The lesions were consistent with florid, papillary endosalpingiosis (FPE), a hitherto unreported condition in a supradiaphragmatic location. Metastases from papillary carcinomas of ovary, breast, or thyroid were excluded considering the lesion's immunophenotype (negative for mammaglobin and TTF-1) and the absence of both atypical features and a concurrent abdominal serous tumor. In only one node, lesions co-existed with a metastasis of breast carcinoma. Supradiaphragmatic FPE represents a pitfall in the differential diagnosis of metastases, especially in sentinel nodes, since it may increase their size and reveal an unusual ultrasonographic image. Clinicopathologic findings and a focused immunohistochemical study led to the correct diagnosis of this benign lesion.

Polypoid endometriosis of the uterine cervix with Arias-Stella reaction in a patient taking phytoestrogens.

We report for the first time a case of 2.5 cm polypoid cervical endometriosis with a superficial growth pattern in a 48-year-old patient with past tubal ligation. The lesion showed metaplastic changes (clear cell, eosinophilic, micropapillary) and a prominent Arias Stella reaction in the absence of concomitant pregnancy but presumably related to phytoestrogenic treatment. The eutopic endometrium, however, had a usual proliferative appearance, implying that it showed a different response from the endometriotic tissues, suggesting the possibility of a metaplastic origin for the endocervical polypoid endometriosis. The unusual histology of the lesion led to an erroneous diagnosis of papillary serous carcinoma in the biopsy. This was subsequently excluded on finding endometrial-type stroma surrounding glands, and was confirmed immunohistochemically by a low Ki-67 index and negativity for p53.