Genotypic and phenotypic progression in endometrial tumorigenesis: determining when defects in DNA mismatch repair and KRAS2 occur.

We set out to determine the relative timing of loss of DNA mismatch repair and KRAS2 mutation in endometrial tumorigenesis. We studied endometrial carcinoma (CA) and synchronous atypical endometrial hyperplasia (AEH), the premalignant precursor of endometrial cancer. Carcinoma and hyperplasia were investigated for loss of mismatch repair as evidenced by microsatellite instability (MSI) and for KRAS2 mutations. Endometrial cancers previously shown to be MSI-positive were evaluated for KRAS2 codon 12 and 13 mutations. DNA was isolated from foci of AEH concomitant with, but physically remote from, the cancers by use of tissues prepared by laser capture microdissection (LCM). The AEH DNAs were then assessed for MSI and KRAS2 mutations. Of 210 endometrial CAs investigated, 51 (26%) were MSI-positive, and among those, 21 (41%) arose concomitantly with AEH. Of 41 foci of AEH (mean, two foci per patient) investigated, 34 (83%) were MSI-positive. KRAS2 mutations were seen in 5/51 (10%) MSI-positive carcinomas. From the five patients informative for both KRAS2 mutation and MSI, 10 foci of AEH were available for investigation. All 10 AEH specimens (100%) were MSI-positive, and six (60%) had the KRAS2 mutation present in the coexisting CA. The observation that some MSI-positive AEH specimens lack the KRAS2 mutation seen in the coexisting CA supports a model in which loss of DNA mismatch repair precedes KRAS2 mutation. However, in addition to the absence of KRAS2 mutations in AEH, we discovered mutations in LCM hyperplasia and carcinoma specimens that were not present in the portion of the cancers originally investigated. These discordant genotypes suggest genetic heterogeneity in endometrial hyperplasia and concomitant cancer.

Loss of heterozygosity at 11q23.3 in vasculoinvasive and metastatic squamous cell carcinoma of the cervix.

We have previously demonstrated a strong relationship between loss of heterozygosity (LOH) at chromosome 11q23.3 and the presence of extensive tumor plugs in lymphvascular spaces (LVS) in stage 1B cervical carcinoma, suggesting that genes at this locus may regulate vasculoinvasion. This study examined LOH at 11q23.3 in microdissected tumor plugs within LVS and in metastatic foci in lymph nodes (MFLN), as well as corresponding invasive tumor and adjacent cervical intraepithelial neoplasia (CIN) 3 in stage 1B squamous cell carcinoma. Of 49 invasive carcinomas, 38.8% had LOH at 11q23.3. Of 36 tumor plugs in LVS, 39% had LOH at 11q23.3. Twenty percent of 15 MFLN demonstrated LOH at 11q23.3. Patients with LOH at 11q23.3 are significantly more likely to have disease recurrence than patients without LOH at 11q23.3 (P =.02). Of 10 foci of CIN 3, none showed LOH at 11q23.3. Although unlikely to have an impact early in carcinogenesis, tumor-suppressor genes located in the region of 11q23.3 appear to be important in tumor progression, facilitating lymphvascular space invasion and, by inference, spread to lymph nodes in squamous cell carcinoma of the cervix.

Cell proliferation in ovarian carcinoma: superior accuracy of S-phase fraction (SPF) by DNA labeling index versus flow cytometric SPF, lack of independent prognostic power for SPF and DNA ploidy, and limited effect of SPF on tumor growth rate.

OBJECTIVES: The goal of this work was to test the hypotheses that S-phase fraction (SPF) by DNA labeling index (SPF-LI) would predict the course of the disease for ovarian/peritoneal carcinomas and that SPF-LI would correlate better with pathologic classification and outcome than SPF by DNA flow cytometry (SPF-F). METHODS: Tritiated thymidine (1985-1988) and bromodeoxyuridine (1988-1999) DNA labeling (SPF-LI) was evaluated in vitro on 178 tumors. Cellular DNA and SPF-F were measured flow cytometrically. During this time, 90% of ovarian/peritoneal tumors accessioned in surgical pathology were studied. RESULTS: Tumors of low malignant potential (LMP, "borderline") had low SPF-LI (median = 1.2%). High-grade invasive carcinomas of various types and carcinosarcomas all had high SPF-LI (medians = 11.2-23.4%). Serous low-grade invasive carcinomas (median = 1.05) resembled LMP tumors. SPF-LI of ovarian carcinomas other than LMP tumors increased slightly as FIGO stage increased (P = 0.07). Survival of patients with high-grade ovarian carcinomas was not predicted by SPF-LI or SPF-F, nor was DNA ploidy predictive. SPF-LI produced tighter distributions for various tumor types than did SPF-F. Neither SPF nor DNA ploidy contributed to prediction of outcome when tumor type and stage were included in multivariate models. We calculated the mean cell loss rate of high-grade carcinomas to be 94%. CONCLUSIONS: LMP ovarian/peritoneal tumors have low proliferation rates in contrast to high-grade carcinomas. Proliferation correlated with tumor type and stage, but neither it nor DNA ploidy predicted survival independently. Proliferation rate is growth limiting only when low. At higher levels cell loss limits growth. SPF-LI measures proliferation more accurately than SPF-F; SPF-F is not sufficiently reliable for clinical use.

Absence of PTEN repeat tract mutation in endometrial cancers with microsatellite instability.

OBJECTIVE: PTEN, a tumor suppressor gene shown to be frequently mutated in endometrial cancers, has been suggested to be a target of microsatellite instability (MSI)-driven mutagenesis. We set out to investigate the relationship between MSI and PTEN mutation in a large series of primary endometrial carcinomas. METHODS: Thirty-nine MSI-positive endometrial cancers were evaluated by single-strand conformational variant analysis and direct sequencing to screen all nine PTEN exons for mutation. RESULTS: Fifteen specimens (38%) demonstrated 16 PTEN mutations. We observed only one alteration in the poly-adenine repeat of exon 8 that is suggested to be a target for mutation in endometrial cancers with MSI. Seven of 16 (44%) mutations in our series were deletions of >/=3 bp, a class of mutation not usually associated with tumors with defective DNA mismatch repair. To determine the significance of this high frequency of deletion, 26 additional endometrial cancers without MSI were matched with the 39 MSI-positive cancers for the prognostic factors of tumor histology, stage, grade, and patient race. The MSI-positive tumors had a significantly higher frequency of deletions involving >/=3 bp when compared with the MSI-negative group (5/11 versus 0/10, P = 0.035). CONCLUSIONS: Repeat tract mutation in PTEN is an uncommon event in MSI-positive cancers. Deletion of >/=3 bp in this gene is more common in MSI-positive cancers when compared with tumors without MSI.

MLH1 promoter methylation and gene silencing is the primary cause of microsatellite instability in sporadic endometrial cancers.

Defective DNA mismatch repair in human tumors leads to genome-wide instability of microsatellite repeats and a molecular phenotype referred to as microsatellite instability (MSI). MSI has been reported in a variety of cancers and is a consistent feature of tumors from patients with hereditary non-polyposis colorectal cancer. Approximately 20% of cancers of the uterine endometrium, the fifth most common cancer of women world-wide, exhibit MSI. Although the frequency of MSI is higher in endometrial cancers than in any other common malignancy, the genetic basis of MSI in these tumors has remained elusive. We investigated the role that methylation of the MLH1 DNA mismatch repair gene plays in the genesis of MSI in a large series of sporadic endometrial cancers. The MLH1 promoter was methylated in 41 of 53 (77%) MSI-positive cancers investigated. In MSI-negative tumors on the other hand, there was evidence for limited methylation in only one of 11 tumors studied. Immunohistochemical investigation of a subset of the tumors revealed that methylation of the MLH1 promoter in MSI-positive tumors was associated with loss of MLH1 expression. Immunohistochemistry proved that two MSI-positive tumors lacking MLH1 methylation failed to express the MSH2 mismatch repair gene. Both of these cancers came from women who had family and medical histories suggestive of inherited cancer susceptibility. These observations suggest that epigenetic changes in the MLH1 locus account for MSI in most cases of sporadic endometrial cancers and provide additional evidence that the MSH2 gene may contribute substantially to inherited forms of endometrial cancer.

Mapping an endometrial cancer tumor suppressor gene at 10q25 and development of a bacterial clone contig for the consensus deletion interval.

Frequent loss of chromosome 10q sequences in endometrial cancers suggests the involvement of a tumor suppressor gene. Previous loss-of-heterozygosity (LOH)studies have pointed to the 10q25-q26 region as the likely site of a tumor suppressor involved in endometrial tumorigenesis (S. L. Peiffer et al., 1995, Cancer Res. 55: 1922-1926; S. Nagase et al., 1996, Br. J. Cancer 74: 1979-1983; S. Nagase et al.,1997, Cancer Res. 57: 1630-1633). In an attempt to define further the localization of a tumor suppressor gene at 10q25, we screened a panel of 123 endometrioid adenocarcinomas for loss of heterozygosity of 10q25.3 sequences. Forty-three (35%) revealed LOH at one or more loci. The observed patterns of allelic loss define a minimum consensus region of deletion between D10S221 and D10S610. A sequence-ready bacterial clone contig and a long-range restriction map for a 1-Mb interval spanning the deletion region were developed as the first step in experiments directed toward the discovery the 10q25 tumor suppressor.

Hepatic (hepatocellular) adenoma of the placenta: a study of four cases.

Hepatic (hepatocellular) adenoma of the placenta is an extremely rare nontrophoblastic placental lesion of disputed histogenesis, four examples of which were diagnosed over a 10-year period. The lesions, which were incidental findings in women 21 to 30 years of age (mean, 25; median, 24.5), ranged from 0.3 to 1.0 cm in greatest dimension. Two were found within the villous parenchyma and two in subchronic locations. On cross section, two examples were tan to dark red nodules without necrosis or hemorrhagic foci, whereas two were not visible grossly. The lesions were composed of semidistinct lobules of cords and nests of polygonal epithelial cells resembling fetal liver. Extramedullary hematopoiesis was a constant feature. The lesional cells contained glycogen and were immunoreactive for cytokeratin, alpha-fetoprotein, alpha-1-antitrypsin, and carcinoembryonic antigen. Although the histogenesis of these lesions remains uncertain, an origin from displaced yolk sac elements with hepatocytic differentiation is the most likely hypothesis. It is important to distinguish hepatic adenoma of the placenta from placental cell island, heterotopic adrenocortical nodule, chorangioma, and placental metastasis of maternal and fetal malignancies.

Loss of heterozygosity in clinical stage IB cervical carcinoma: relationship with clinical and histopathologic features.

Loss of heterozygosity (LOH) has been shown to be an important prognostic factor in a variety of malignant neoplasms. The relationship between LOH and established histopathological prognostic factors in cervical carcinoma has not been examined. We studied LOH in 58 FIGO stage IB cervical cancers treated by radical hysterectomy. In a randomly selected subset of 37 of these cases, LOH was examined using markers for all 41 chromosomal arms. Seventy-six percent of the 58 cases and 95% of the extensively studied cases showed LOH at one or more loci. The three most common sites of LOH were 3p21, 6p24-p23, and 11q23.3. In the extensively studied group, LOH on 11q was associated with extensive lymphvascular space invasion (P = .009) and less deeply invasive tumor (P = .042). There was a trend for tumors with LOH on 11q to recur, but this was not statistically significant. No correlation between the presence of LOH on 3p or 6p and lymphvascular space invasion or tumor depth was present. There was no correlation between the number of sites of LOH or between the presence of LOH on 3p, 6p, and 11q and the presence of metastatic tumor in regional lymph nodes, histologic type (squamous v nonsquamous), tumor differentiation, maximum tumor size, degree of inflammation, pattern of invasion, mitotic rate, or clinical recurrence. In summary, tumors with 11q LOH may behave in a more aggressive fashion. Future studies of LOH in cervical carcinoma should include histopathological prognostic information so that the relationship between LOH and these factors can be determined on larger numbers of patients.

Large cell neuroendocrine [corrected] carcinoma of the uterine cervix: a clinicopathologic study of 12 cases.

Twelve cervical tumors showing morphologic evidence of neuroendocrine differentiation and lesional cells larger than those of typical small cell carcinoma are reported in women 21 to 62 (mean 34) years of age. The patients presented with an abnormal Papanicolaou smear or vaginal bleeding. Two tumors were stage Ia2, nine were stage Ib, and one was stage IIa. All patients were treated by radical hysterectomy, and most received adjuvant chemotherapy. Seven of 10 patients with > 1 year of follow-up died of tumor 6 to 24 months after hysterectomy. The tumors had insular, trabecular, glandular, and solid growth patterns and contained medium to large cells with moderate to abundant cytoplasm; eosinophilic cytoplasmic granules were present in nine cases. The tumors were mitotically active, and necrosis was present in 10 of them. Nine of 10 tumors were argyrophilic, and all 12 were immunoreactive for chromogranin. Individual cells containing somatostatin, serotonin, or glucagon were identified in four of eight cases. Adenocarcinoma in situ was present adjacent to the tumor in eight cases; invasive adenocarcinoma of non-neuroendocrine type was present in three of these tumors. Using diagnostic criteria established for pulmonary neuroendocrine tumors, the 12 tumors were classified as large cell neuroendocrine carcinomas. Cervical large cell neuroendocrine carcinomas are distinctive cervical carcinomas that are frequently misdiagnosed and have an unfavorable outcome, similar to that of small cell carcinoma.

Frequent deletion of chromosome 1p sequences in an aggressive histologic subtype of endometrial cancer.

The molecular genetic events underlying endometrial tumorigenesis are ill-defined at present. We have identified a region on the short arm of chromosome 1 which is frequently deleted in endometrial cancers. The region of deletion has been localized to bands 1p32-33. Deletion of 1p32-33 is seen more frequently in cancers of the highly aggressive papillary serous type than in cancers of the less-aggressive endometrioid type. These data suggest the presence of a tumor suppressor gene on 1p32-33 which is specifically involved in the development of endometrial cancers with poor outcome.

Ovarian granulosa cell tumors with bizarre nuclei: an immunohistochemical analysis with fluorescence in situ hybridization documenting trisomy 12 in the bizarre component [corrected].

Granulosa cell tumors with bizarre nuclei (GCT-BN) are rare lesions with a prognosis apparently similar to that of conventional granulosa cell tumors (GCT-NOS). The immunohistochemical features of GCT-BN have not been described, and the exact nature of the bizarre nuclei (BN) is unclear. Thirteen GCT-BN were studied with antibodies to cytokeratin, vimentin, epithelial membrane antigen, muscle-specific actin, alpha smooth muscle actin, desmin, and S-100 protein. Six cases were also examined by fluorescence in situ hybridization for trisomy 12, a nonrandom chromosomal aberration found in a proportion of ovarian sex-cord stromal tumors. Histologically, 12 tumors (86%) contained BN areas interspersed with large areas of GCT-NOS. The remaining tumor contained only microscopic foci of GCT-NOS. Immunohistochemically, the tumors stained for vimentin (13 tumors), S-100 protein (11 tumors), muscle-specific actin (10 tumors), cytokeratin (eight tumors), alpha smooth muscle actin (eight tumors), and desmin (one tumor), but none stained for epithelial membrane antigen. Immunostaining results for the BN and GCT-NOS areas were concordant in eight (73%) of the 11 tumors in which both areas could be independently assessed. The remaining three tumors (27%) showed discordant results for only one of the eight markers used. In five patients, trisomy 12 was detected by fluorescence in situ hybridization in areas of BN but not in areas of GCT-NOS present in the same tumor. Trisomy 12 was also present in another BN tumor in which the foci of GCT-NOS were too small to be evaluated. We conclude that within GCT-BN, areas with BN are immunohistochemically similar to areas of GCT-NOS present in the same tumor. The finding of trisomy 12 in areas with BN but not GCT-NOS in the same tumor, however, suggests that cells with BN represent a genetically distinct clone of tumor cells arising within GCT-NOS.

Selected vascular lesions of the placenta.

The double circulation of the placenta results in great diversity in the morphologic expression of vascular lesions. Although the etiology and pathogenesis of many of these lesions are not completely understood, it is clear that some have potentially serious implications for fetal well-being. This article focuses on the diagnostic criteria and clinical significance of selected placental vascular lesions.

Allelic loss of sequences from the long arm of chromosome 10 and replication errors in endometrial cancers.

Thirty-seven endometrial cancers were subjected to an allelotype analysis in an attempt to identify chromosomal regions that are lost in a significant portion of tumors and to identify tumors characterized by replication errors. Thirty-nine highly polymorphic microsatellite markers representing all chromosomal arms, excluding the X and the short arms of the acrocentrics, were examined. An average of 20 informative cases were evaluated for each marker. Genetic alterations were detected in 30 of the 37 tumors. Replication errors were identified in 8 tumor specimens. Loss of heterozygosity was observed for loci on all chromosomes examined with the exception of chromosomes 4 and 20. The two most frequent sites of loss were at the marker loci examined on 10q (40%) and 17p (29%). Six additional simple sequence repeat markers from 10q were genotyped in an effort to refine the region of 10q loss. The chromosome 10 markers used in these studies were physically mapped with the use of a panel of somatic hybrids that retain defined portions of chromosome 10. The observed patterns of loss of sequences on 10q suggest a role for a tumor suppressor gene in the 10q23-26 region in the development or progression of endometrial cancers.

Congenital syphilis: a reminder about the return of an old scourge.

Congenital syphilis had almost become a forgotten disease with the advent of maternal prenatal serology and penicillin therapy for infected mothers. From the 1950s into the mid-1980s, cases of congenital syphilis steadily declined to only 688 cases in the United States in 1988; however, the number of cases increased to 2,841 by 1990. The heralding event occurred between 1981 and 1989 with a 34% increase nationally in the incidence of primary and secondary syphilis. A peak in the number of cases of congenital syphilis was attained in 1992 in the country at large, but in 1993 in the State of Missouri, there were almost three times as many cases as were reported in 1992. Physicians, particularly those who practice in the metropolitan areas of the state, should be alert to the clinical profile of prospective mothers who may have primary or secondary syphilis.

Uterine leiomyomas with high content of mast cells.

We report nine cases of uterine leiomyomas with an average of more than 10 mast cells per high-power field. The clinical presentation and morphological features of the tumors did not differ from those of conventional leiomyomas. Two cases also showed eosinophilia. The adjacent myometrium did not show an increased number of mast cells. Mast cells are frequently numerous in leiomyomas, but the significance of this finding is unknown.

Placental site nodule: a clinicopathologic study of 38 cases.

This report describes the clinical, histological, and immunohistochemical features of 38 cases of placental site nodule (PSN), a recently described lesion of intermediate trophoblast (IT). The patients ranged in age from 20 to 47 years (mean, 31.1 years). PSNs were diagnosed in endometrial (30 cases), endocervical (seven cases), and both endometrial and endocervical specimens (one case). The majority of biopsies were prompted by an abnormal Pap smear (13 cases) or complaints of menorrhagia (21 cases). All PSNs were microscopically detected, lobulated nodules composed of acellular, hyalinized material admixed with IT. Mitotic activity was noted in seven cases. Immunohistochemically, the IT expressed human placental lactogen (hPL) in 78% of cases and human chorionic gonadotropin (hCG) in 42% of cases, but their expression was weak and focal in contrast to uniform, strong staining for placental alkaline phosphatase (PLAP) (100%), cytokeratins (96%), and epithelial membrane antigen (EMA) (84%). Type IV collagen outlined the IT and stained the extracellular material in the cellular areas. Vimentin-positive cells within the lesions were fewer in number and in a different distribution than those expressing PLAP, CK, and EMA. Two consecutive PSNs occurred in one patient, but no patient developed gestational trophoblastic disease or a significant gynecologic neoplasm.

Arias-Stella reaction in nonpregnant women: a clinicopathologic study of nine cases.

The Arias-Stella reaction (ASR) is a common and universally recognized feature of gestational endometrium. That identical cytologic changes may, on occasion, occur outside the endometrium or in nonpregnant women is not as well documented. This report describes the clinical and pathologic findings in nine nonpregnant women whose endometria demonstrated ASR. The defining characteristics of ASR, associated pathologic changes, and differential diagnosis are discussed. All of these women were peri- or postmenopausal, and eight of nine had received exogenous hormones, most (n = 7), progestational agents. ASR did not persist in the four patients who underwent subsequent endometrial examination. None of these patients developed adenocarcinoma, although follow-up was short. ASR is an unusual response to hormonal therapy in nonpregnant patients. It is important to recognize the phenomenon in this setting and not overinterpret the characteristic cytologic atypia as adenocarcinoma.

Extramedullary hematopoiesis in the endometrium. Report of four cases and review of the literature.

Extramedullary hematopoiesis is extremely rare in the absence of any hematologic disorder or systemic disease, and there have been no reports of this condition in the endometrium. The authors describe the cases of four patients who complained of irregular uterine bleeding, lower abdominal pain, or both. Microscopic examination of the curetted endometria showed chronic inflammation in two patients, chronic inflammation and leiomyomas in one patient, and a well-differentiated adenosquamous adenocarcinoma with adenomyosis and leiomyomas in one patient. Light-microscopic examination of curetted sections from all four patients revealed isolated foci of extramedullary hematopoiesis composed of one or more lineages of blood cell precursors. Sufficient tissue was available from two patients to confirm hematopoietic differentiation through immunohistologic analysis, using antibodies to von Willebrand factor, ABH blood group antigens, CD34, and CD15.