C-kit protein expression in uterine and ovarian mesenchymal tumours

Gastrointestinal Stromal Tumor with Repeated Multiple Cerebral Infarction Mimicking Ovarian Cancer with Trousseau’s Syndrome

We report a case of gastrointestinal stromal tumor (GIST) with repeated multiple cerebral infarctions mimicking ovarian cancer. A 79-year-old postmenopausal woman had multiple cerebral infarctions with a giant pelvic tumor detected by computed tomography. Ovarian cancer with Trousseau's syndrome was suspected. Through laparoscopic biopsy on the tumor surface, she was diagnosed with left ovarian fibrosarcoma; although, the abdominal cavity could not be observed appropriately. Ovarian fibrosarcoma is an extremely rare tumor and still has no adequate treatment strategy. Complete resection was planned. The tumor was extremely fragile, and gelatinous that it easily bled. Meanwhile, the uterus and bilateral ovaries and fallopian tubes were all normal. The tumor invaded only the peritoneum near the left sacral uterine ligament and sigmoid colon, with no peritoneal dissemination. To completely remove the tumor, we performed total hysterectomy with bilateral salpingo-oophorectomy and omentectomy and sigmoidal and rectal resection with colostomy. Despite resuming her anticoagulant therapy on postoperative day 4, she had recurrent multiple strokes. On histopathological examination, tumor showed spindle cell proliferation with severe atypia, increased mitotic activity, and widespread necrosis. Immunohistochemical studies showed positive staining for c-kit, CD34, and DOG1. Thus, she was diagnosed with GIST. This case was rare and highly malignant, with a high risk of recurrence of GIST because of a giant ruptured tumor that had a mitotic activity of 36/10 high-power fields from the sigmoid colon. Multiple cerebral infarctions mimicking ovarian cancer recurred. Therefore, preoperative diagnosis of an atypical GIST was extremely difficult.

Recently discovered interstitial cells "telocytes" as players in the pathogenesis of uterine leiomyomas

Uterine telocytes are interstitial cells characterized by a very long cytoplasmic prolongations, which form a 3D network, functionally integrating a wide variety of different cells. Leiomyomas (uterine fibroids) are benign tumors, which pose a huge threat concerning various health problems in women affected by this condition. The exact cause of leiomyomas development is, however, still largely unknown. Therefore, in an attempt to clarify their etiology, we performed an immunohistochemical characterization of telocytes in leiomyomas as well as in normal myometrium. Tissue samples of intramural leiomyomas from 26 women (age 46.26 ± 11.07) were immunohistochemically stained for the expression of c-kit (CD117) antigen, one of the markers of telocytes. C-kit (CD117) antigen is useful for a routine immunohistochemical identification of uterine telocytes in histological sections of myometrium. In normal, healthy myometrium the c-kit positive telocytes occupy approximately 2.2% of the area of a tissue slide, contrasting with no detectable c-kit positive cells within leiomyomas. As telocytes are thought to be key players in the regulation of tissue homoeostasis, our data suggest that uterine telocyte loss may have important implications in the pathogenesis of leiomyomas. In addition, we supposed to summarize three hypotheses on the association of the cells telocytes loss within the myometrium and formation of leiomyomas. These hypotheses include the loss of telocytes' functions as "sex hormone sensors" and regulators of smooth muscle cells cycle; the role of telocytes as progenitor cells for the development of leiomyomas; and the hypothesis of decreased angiogenesis after telocytes' loss with subsequent hypoxia (as a key factor for leiomyomas development).

Uterine Adenosarcoma: a Review

Adenosarcomas are rare malignancies of the female genital tract, accounting for approximately 5 % of uterine sarcomas. Occasionally, adenosarcoma occurs in the ovaries or in extra-uterine tissue, which may be related to endometriosis. These tumors are characterized by benign epithelial elements and a malignant mesenchymal component. Pathologic diagnosis is dependent on the identification of the characteristic morphologic features. The most common immunohistochemical markers for adenosarcoma are CD10 and WT1, but these are not specific. The most frequent presenting symptom is abnormal uterine bleeding. The majority of patients present with stage I disease, with a 5-year overall survival of 60 to 80 %. Survival is influenced by the presence of myometrial invasion, sarcomatous overgrowth, lymphovascular invasion, necrosis, and the presence of heterologous elements including rhabdomyoblastic differentiation. Patients with sarcomatous overgrowth have significantly increased risk of recurrence 23 versus 77 % and decreased 5-year overall survival 50 to 60 %. Standard of care treatment is total hysterectomy with bilateral salpingo-oophorectomy without lymphadenectomy, as the incidence of lymph node metastasis is rare. Retrospective data does not support the use of adjuvant pelvic radiotherapy in uterine adenosarcomas as no survival benefit is seen. Insufficient data exists to recommend routinely neoadjuvant or adjuvant chemotherapy for uterine adenosarcomas. Limited evidence exists for the role of hormonal therapy in uterine adenosarcomas. The PIK3/AKT/PTEN pathway is mutated in ∼70 % of adenosarcomas, and this may represent a possible therapeutic target. This article reviews the current state of knowledge concerning uterine adenosarcoma and discusses the management of this rare tumor.

Review of Recommended Treatment of Uterine Carcinosarcoma

Surgery is the primary treatment for uterine carcinosarcoma (UCS). Lymphadenectomy should be performed for staging purposes in tumors apparently confined to the uterus. Most studies found that lymphadenectomy is of therapeutic value. The therapeutic value of cytoreduction to no residual macroscopic disease in advanced UCS is based mostly on small retrospective uncontrolled studies. Postoperative adjuvant therapy should be considered for all stages of UCS. Adjuvant pelvic radiotherapy may reduce locoregional recurrences. However, this does not translate into improved overall survival since most recurrences are distant outside the irradiated field, and the survival rates remain poor, the 5-year overall survival being about 50%. Several adjuvant platin-based combination chemotherapy schedules such as cisplatin/ifosfamide, ifosfamide/paclitaxel, and paclitaxel/carboplatin have been found to be an effective mode of adjuvant treatment. Multimodal therapy (i.e., adjuvant chemotherapy plus radiotherapy) has also been shown to be effective. Most studies dealing with adjuvant treatment are retrospective and prospective randomized controlled trials (i.e., phase III studies) comparing that between the various adjuvant chemotherapy schedules and between them and multimodal treatment are lacking. Quality of life with the various treatment modalities needs also to be assessed. An effective targeted therapy has so far not been found. In spite of the multiple studies with regard to the treatment of UCS published during the last 15 years, the optimal management of UCS is still not established.

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-β, and ABL on 28 ESS. EGFR, PDGFR-α, and PDGFR-β 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-β 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-β. 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.

DOG1 immunoreactivity in uterine leiomyosarcomas

AIMS

DOG1 is a recently described marker of gastrointestinal stromal tumour (GIST) which is considered to be extremely sensitive and, among mesenchymal neoplasms, quite specific for this tumour type. Following the identification of DOG1 immunoreactivity in a uterine leiomyosarcoma, we wished to ascertain how prevalent DOG1 immunoreactivity was in this tumour type.

METHODS

We stained a series of uterine leiomyosarcomas (n=26) with DOG1 and with CD117 (c-kit), another marker of GIST. Staining with both markers was classified as negative, focal (<50% tumour cells positive) or diffuse (≥50% tumour cells positive).

RESULTS

DOG1 immunoreactivity was present in seven of 26 (27%) leiomyosarcomas. Staining was focal in five cases and diffuse in two. CD117 was positive in three of 26 (11.5%) cases, two focal and one diffuse. Two cases were positive with DOG1 and CD117. One of five uterine leiomyomas was focally positive with DOG1, and one extrauterine pelvic leiomyoma was diffusely positive with this marker.

CONCLUSIONS

Since GISTs have rarely been described as primary uterine neoplasms, the presence of DOG1 immunoreactivity in a uterine leiomyosarcoma may result in diagnostic confusion, and a panel of markers is necessary for diagnosis. Uterine leiomyosarcomas should be added to the list of mesenchymal neoplasms which may be DOG1 positive.

Immunohistochemical Markers of Value in the Diagnosis of Mesenchymal Lesions of the Female Genital Tract

Pure mesenchymal tumors may occur anywhere in the female genital tract, but they are most common in the uterine corpus, leiomyoma being by far the most prevalent. These tumors, and other uncommon mesenchymal lesions within the uterine corpus and elsewhere in the female genital tract, may result in several diagnostic problems. Morphology remains paramount and, in most cases, an unequivocal diagnosis can be made based on examination of the hematoxylin and eosin stained sections, combined with an appreciation of the clinical and gross pathologic features. In difficult cases, immunohistochemistry can significantly contribute to the final diagnosis. In this article, the immunohistochemistry of neoplastic and nonneoplastic mesenchymal lesions of the female genital tract is discussed site by site, concentrating on markers that are of value in diagnosis and in differential diagnosis. The immunophenotype of mixed epithelial and mesenchymal neoplasms and pure epithelial neoplasms with a component of spindle cells is discussed, where appropriate, because these can enter into the differential diagnosis of a pure mesenchymal lesion.

Constitutive activation of Beta-catenin in uterine stroma and smooth muscle leads to the development of mesenchymal tumors in mice

Leiomyomas and other mesenchymally derived tumors are the most common neoplasms of the female reproductive tract. Presently, very little is known about the etiology and progression of these tumors, which are the primary indication for hysterectomies. Dysregulated WNT signaling through beta-catenin is a well-established mechanism for tumorigenesis. We have developed a mouse model that expresses constitutively activated beta-catenin in uterine mesenchyme driven by the expression of Cre recombinase knocked into the Müllerian-inhibiting substance type II receptor promoter locus to investigate its effects on uterine endometrial stroma and myometrium. These mice show myometrial hyperplasia and develop mesenchymal tumors with 100% penetrance that exhibit histological and molecular characteristics of human leiomyomas and endometrial stromal sarcomas. By immunohistochemistry, we also show that both transforming growth factor beta and the mammalian target of rapamycin are induced by constitutive activation of beta-catenin. The prevalence of the tumors was greater in multiparous mice, suggesting that their development may be a hormonally driven process or that changes in uterine morphology during pregnancy and after parturition induce injury and repair mechanisms that stimulate tumorigenesis from stem/progenitor cells, which normally do not express constitutively activated beta-catenin. Additionally, adenomyosis and endometrial gland hyperplasia were occasionally observed in some mice. These results show evidence suggesting that dysregulated, stromal, and myometrial WNT/beta-catenin signaling has pleiotropic effects on uterine function and tumorigenesis.

Persistent hypomethylation in the promoter of nucleosomal binding protein 1 (Nsbp1) correlates with overexpression of Nsbp1 in mouse uteri neonatally exposed to diethylstilbestrol or genistein

Neonatal exposure of CD-1 mice to diethylstilbestrol (DES) or genistein (GEN) induces uterine adenocarcinoma in aging animals. Uterine carcinogenesis in this model is ovarian dependent because its evolution is blocked by prepubertal ovariectomy. This study seeks to discover novel uterine genes whose expression is altered by such early endocrine disruption via an epigenetic mechanism. Neonatal mice were treated with 1 or 1000 microg/kg DES, 50 mg/kg GEN, or oil (control) on d 1-5. One group of treated mice was killed before puberty on d 19. Others were ovariectomized or left intact, and killed at 6 and 18 months of age. Methylation-sensitive restriction fingerprinting was performed to identify differentially methylated sequences associated with neonatal exposure to DES/GEN. Among 14 candidates, nucleosomal binding protein 1 (Nsbp1), the gene for a nucleosome-core-particle binding protein, was selected for further study because of its central role in chromatin remodeling. In uteri of immature control mice, Nsbp1 promoter CpG island (CGI) was minimally methylated. Once control mice reached puberty, the Nsbp1 CGI became hypermethylated, and gene expression declined further. In contrast, in neonatal DES/GEN-treated mice, the Nsbp1 CGI stayed anomalously hypomethylated, and the gene exhibited persistent overexpression throughout life. However, if neonatal DES/GEN-treated mice were ovariectomized before puberty, the CGI remained minimally to moderately methylated, and gene expression was subdued except in the group treated with 1000 microg/kg DES. Thus, the life reprogramming of uterine Nsbp1 expression by neonatal DES/GEN exposure appears to be mediated by an epigenetic mechanism that interacts with ovarian hormones in adulthood.

Current status and issues in cancer stem cell study

Cancer stem cells (CSCs) have been positively identified and successfully isolated from some but not all cancers. The studies on CSCs to date suggest that these cells are rare among the tumor cell population, and they are capable of self-renewing and maintaining tumor growth and heterogeneity. Therapies aimed at CSCs have shown some promise, but their further development will require a more thorough understanding of the biology of CSCs and methods for identifying and isolating this cell subpopulation. This review examines what is known to date regarding the similarities and differences between cancer and somatic stem cells: CSC surface marker development and cell isolation (including a model isolation from our lab), the frequency, potential origin, and signal transduction of CSCs, and the current state of CSC-targeting therapeutic strategies.

Expression of insulin-like growth factor-1 receptors, Wilm's tumor-1 protein, c-kit and p16 in primary fallopian tube carcinoma in diabetic patients

BACKGROUND

Primary fallopian tube carcinoma (PFTC) represents less than 1% of all gynecological malignancies and its association with diabetes mellitus is seldom reported.

CASES

We report three cases of PFTC presented primarily as advanced ovarian cancer while the primary site totally silent. Two of them were diabetics and showed expression of insulin-like growth factor receptors, Wilm's tumor protein-1, c-kit and P16. In all these cases there was neither clinical nor perioperative suspicion of PFTC and the first clinical diagnosis was ovarian carcinoma which was supported by positive cytology for ascitic fluid and raised serum level of CA125. The diagnosis was only established after histopathologic examination of serial sections of the whole fallopian tube since we were able to demonstrate the continuity between the invasive and the in situ components of PFTC in the lining epithelial layer of the fallopian tube.

CONCLUSION

The presence of malignant cells in the female pelvic organs without a mass should raise the possibility of primary fallopian tube carcinoma. Pre-operative diagnosis of PFTC is seldom made and most of the time the diagnosis is made after histopathological examination as in our cases. Diabetes mellitus can be a risk factor in the development of PFTC.