Strong expression of vascular permeability factor (vascular endothelial growth factor) and its receptors in ovarian borderline and malignant neoplasms.

Angiogenesis is a critical factor in the growth, progression, and metastatic spread of solid tumors. Furthermore, angiogenesis has been correlated with prognosis in patients with ovarian cancer. The pathogenesis of the angiogenic events in ovarian cancer, however, are not well defined. Vascular permeability factor/vascular endothelial growth factor (VPF/VEGF) is a multifunctional cytokine that has been shown to be an important regulator of tumor angiogenesis. The purpose of the present study was to define the expression of VPF/VEGF and its receptors flt-1 and KDR in ovarian tumors. Four specimens of normal ovarian cortex and 41 specimens of benign (4), borderline (8), and malignant (29) ovarian tumors were studied by in situ hybridization, and in some cases by immunohistochemical analysis. VPF/VEGF protein was also determined by an immunofluorometric assay in cyst fluids obtained from 11 patients, including 7 benign, 2 borderline, and 2 malignant tumors. VPF/VEGF mRNA and protein were expressed by the neoplastic cells in all of the malignant tumors evaluated, with the majority of tumors (28 of 29) showing strong expression of mRNA. Serous borderline tumors had variable VPF/VEGF mRNA expression, with two of six cases showing focal strong expression and four showing low-level expression. No definite expression of VPF/VEGF was seen in two cases of mucinous borderline tumors. No strong expression of VPF/VEGF mRNA was observed in normal ovarian cortex, including surface epithelium, or benign tumors. Substantially higher VPF protein concentrations were detected in cyst fluids of the two malignant (60, 440 pM) and two borderline tumors (210, 590 pM) than in the seven benign serous cysts (mean, 10 +/- 3 pM). In addition, microvascular endothelial cells strongly expressed mRNA of the VPF/VEGF receptors flt-1 and KDR and immunostained for VPF/VEGF protein in the majority of malignant and borderline tumors examined. These findings suggest that VPF/VEGF plays an important role in the angiogenesis associated with ovarian neoplasms.

Qualifiers of atypical squamous cells of undetermined significance help in patient management.

According to the recommendations of the Bethesda System, the diagnosis of atypical squamous cells of undetermined significance (ASCUS) should be further qualified, when possible, as to whether a reactive or a squamous intraepithelial lesion (SIL) is favored. To determine the utility of this recently proposed terminology, we undertook this study to correlate the diagnosis of ASCUS (with or without qualifiers) with results obtained from examination of biopsy specimens. All patients were identified for the study who had a coloposcopically obtained cervical biopsy specimen or endocervical curettage specimen recorded in the surgical pathology files at Beth Israel Hospital, Boston, Massachusetts, from April 1994 through September 1994 and had either prior or concurrent Pap smear(s) reported as ASCUS, ASCUS-favor reactive, ASCUS-favor SIL, or SIL-low grade (SIL-LG). Patients with a cytologic diagnosis of SIL-LG served as a reference group. A total of 435 patients with 485 Pap smears were included. The prevalence rates of biopsy-proven SIL in patients with a cytologic diagnosis of ASCUS-favor reactive, ASCUS, ASCUS-favor SIL, and SIL-LG were 10, 28, 36, and 55%, respectively. The difference between cases diagnosed as ASCUS (with or without qualifiers) and SIL-LG, with respect to the presence of SIL at examination of the biopsy specimen, was statistically significant (P < 0.001 for all correlations). Cases diagnosed as ASCUS-favor reactive had a significantly lower rate of biopsy-proven SIL compared with those diagnosed as ASCUS and ASCUS-favor SIL (P < 0.01 for both correlations). A significant proportion of biopsy specimens with Pap smear diagnosis of ASCUS-favor SIL had SIL-high grade (15%). In contrast, an underlying SIL-high grade is much less likely in patients with ASCUS (unqualified) (3%) or when a reactive process is favored (3%). It seems justified to manage patients with ASCUS-favor SIL in a manner similar to those with SIL-LG. A conservative management seems appropriate for patients with ASCUS and ASCUS-favor reactive.

ThinPrep processing of endoscopic brushing specimens.

To evaluate ThinPrep (Cytyc, Marlborough, MA) processing of endoscopic brushing specimens for cytologic examination, ThinPrep slides and direct smears of 29 gastrointestinal (GI) and 22 bronchial brushings were compared. Clinicians prepared the direct smears. The brush was then immersed in CytoLyt (Cytyc) and one ThinPrep slide made. All cases had corresponding biopsies. Smears and ThinPrep slides were screened and reviewed independently. Screening time per case was recorded. All slides were evaluated for cellularity, quality, cellular preservation, and quantity of diagnostic cells. A diagnosis was rendered for each case. Cytologic and histologic diagnoses were correlated. Follow up was obtained for cases with discrepant histologic and cytologic diagnosis. Twenty-three brushings were from esophagus, 5 stomach, 1 duodenum, and 22 lung. An average of 3.6 direct smears (range 2-6) was made for each case. Average screening time per case was 12 minutes for GI direct smear, 15 minutes bronchial direct smear, 4 minutes GI ThinPrep slide, and 9 minutes bronchial ThinPrep slide. ThinPrep slides were superior to direct smears in cellularity, quantity of diagnostic cells, and quality of slides. ThinPrep slides and direct smears showed comparable cellular preservation. The sensitivity of detecting malignancy by biopsy, direct smears, and ThinPrep slides was 81%, 75%, and 75%, respectively. One false-positive diagnosis was made on cytology with both direct smear and ThinPrep slide, a case with radiation atypia. In conclusion, ThinPrep slides are at least comparable to direct smears in cytologic examination of brushings. However, false-positive diagnosis is a possible potential pitfall.

Estrogen receptor expression is a common feature of ovarian borderline tumors.

PURPOSE: The presence of estrogen receptor (ER) and its therapeutic significance in ovarian borderline tumors (OBT) have not been established. We recently observed a response to tamoxifen therapy given empirically to a patient with unresectable, recurrent serous borderline tumor (SBT). In view of this observation the present study was undertaken to assess ER expression in 51 cases of OBT. MATERIALS AND METHODS: ER expression was determined retrospectively, using an immunohistochemical method on formalin-fixed, paraffin-embedded specimens, from 35 cases of SBTs, 6 cases of mucinous mullerian (MMBT), and 10 cases of mucinous intestinal borderline tumors (MIBT). ER was considered positive if > 5% of tumor epithelial cell nuclei were immunostained. Both SBTs and mucinous borderline tumors (MBTs) were included to determine the influence of histologic type on ER expression. RESULTS: The patients ranged in age from 25 to 77 years (median 43 years for SBTs, 36 years for MMBTs, and 37 years for MIBTs). The stage distribution for the SBTs was stage I in 27 patients (77%), stage II in 4 patients (11.5%), and stage III in 4 patients (11.5%). All patients with MBTs were stage I. ER expression was observed in the majority of cases and correlated with histologic type: 94% (33/35) of SBTs and 100% (6/6) of MMBTs were ER positive compared to 0% (0/10) of MIBTs (P < 0.01). In the SBT category the presence of ER did not correlate significantly with stage or age. In addition, ER was positive in all four SBT implants (including one involved lymph node) and two recurrent SBTs analyzed. CONCLUSION: ER expression is a common feature of SBT and MMBT, but not MIBT. The relevance of ER expression in the pathogenesis and treatment of OBTs requires further investigation.

Histocytological study of squamous atypia on Pap smears.

UNLABELLED: The significance of squamous atypia on Pap smears is currently unclear and its management is controversial. We undertook this study to determine whether cytological parameters on Pap smears with a diagnosis of squamous atypia could be useful in predicting the presence of a squamous intraepithelial lesion (SIL). METHODS: For a 3-mo period, all patients who had a colposcopically directed biopsy and or endocervical curettage (ECC) with a simultaneous or a previous Pap smear showing squamous atypia were identified. All biopsies were reviewed and all cytological smears were evaluated for the following cytological parameters: inflammation, parakeratosis, atypical parakeratosis, number of atypical cells, nuclear size, chromatin pattern (fine, coarse, or hyperchromatic), as well as presence of metaplasia, nuclear membrane irregularity, multinucleation, and nuclear halo in the atypical cells. RESULTS: a total of 97 patients were eligible for the study. The average interval between the Pap smear and colposcopy was 96 days (range, 0 to 364 days). Thirty patients (31%) had SIL on biopsy or ECC, of which 17 (18%) were SIL, low grade, and 13 (13%) were SIL, high grade. Of the 67 that showed no SIL on histology, 24 had inflammatory reactive changes, five had squamous metaplasia with atypia, one had parakeratosis, and 37 had essentially normal biopsies. Most of the cytological features, except coarse chromatin, were equally predictive of SIL with approximately 30% of the patients with any particular feature showing SIL on histology. However, 46% (17/37) of those that had coarse chromatin showed SIL on histology (P < 0.02). Based on this study, squamous atypia on Pap smears appears a marker of an underlying SIL in a considerable number of cases, and coarse chromatin seems most helpful in predicting the presence of SIL.

Large loop excision of the transformation zone in patients with exocervical squamous intraepithelial lesions.

This study was undertaken to determine factors influencing the success of loop excisions. One hundred twenty-seven women with exocervical intraepithelial lesions underwent large loop excision of the transformation zone (LLETZ); 102 returned for evaluation at 3 months. The pretreatment biopsies were low grade squamous intraepithelial lesions (LGSIL) in 37 cases and high grade squamous intraepithelial lesions (HGSIL) in 90. For the 37 women with LGSIL, the LLETZ specimen revealed no residual SIL in 13 (35%), LGSIL in 16 (43%), and HGSIL in 8 (22%). For the 90 women with HGSIL on pretreatment biopsy, 17 (19%) had no SIL, 10 (11%) had LGSIL, and 63 (70%) had HGSIL. Of the 102 women who returned for reevaluation, colposcopy was satisfactory in 89. There were 9 failures and all of these occurred in women with HGSIL in the LLETZ specimen. In the 17 women with involved margins there were 6 failures (35%); in the 85 women with uninvolved margins there were 3 failures (4%) (p = 0.005). The success of loop excisions is influenced by the grade of intraepithelial neoplasia and status of the margins of the LLETZ specimen.

Rat urate oxidase produced by recombinant baculovirus expression: formation of peroxisome crystalloid core-like structures.

Urate oxidase (EC 1.7.3.3), which catalyzes the oxidation of uric acid to allantoin, is present in most mammals but absent in humans and hominoid primates. In rats and most other mammals that catabolize uric acid to allantoin, this enzyme is localized within the crystalloid cores of peroxisomes present in liver parenchymal cells. To determine whether urate oxidase forms these crystalloid cores or whether core-forming protein(s) exist in association with urate oxidase, a baculovirus expression vector system was used to overproduce the full-length rat urate oxidase in Spodoptera frugiperda cells. Urate oxidase was expressed to a level of approximately 30% of the total protein in this system. Immunoblot analysis demonstrated that the baculovirus-generated protein had electrophoretic and immunologic properties similar to those of urate oxidase expressed in rat liver. Immunofluorescence and electron microscopic examination revealed that the overexpressed recombinant urate oxidase is present in both the cytoplasm and the nucleus of infected insect cells as numerous 1- to 3-microns discrete particles. These insoluble protein aggregates, which were positively stained for urate oxidase by protein A-gold immunocytochemical approach, did not appear to be delimited by a single membrane. They revealed a crystalloid structure reminiscent of rat peroxisomal core consisting of bundles of tubules with an inner diameter of approximately 50 A. The recombinant urate oxidase particles, isolated by a single-step procedure, were composed entirely of 35-kDa urate oxidase subunit. These studies indicate that rat urate oxidase is capable of forming insoluble crystalloid core-like structures.

Amyloidosis in association with human immunodeficiency virus infection.

Amyloidosis has not been previously reported in association with human immunodeficiency virus (HIV) infection. An HIV-infected patient with hemophilia who developed nephrotic syndrome due to amyloidosis is described. Amyloid disease has been observed in monkeys with AIDS, and patients with AIDS have had elevated levels of amyloid A protein, findings that suggest a pathogenetic linkage between the two disorders. Amyloidosis should be considered in the differential diagnosis of HIV-associated nephropathy and the nephrotic syndrome in HIV-infected patients.

Reconstituted basement membrane promotes morphological and functional differentiation of primary human prostatic epithelial cells.

Prostatic epithelial cells undergo rapid proliferation and lose their ability to synthesize and secrete prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP) under standard tissue culture conditions. Herein, we compared the morphology, growth, secretory activity, and intermediate filament expression of human prostatic epithelial cells cultured on either standard tissue culture plastic or reconstituted basement membrane. Epithelial cells grown on plastic exhibited a 10-fold increase in proliferation and a higher percentage of cells in the S-phase of the cell cycle compared to cells cultured on basement membrane. However, cells grown on basement membrane secreted markedly higher levels of PSA and PAP. The basement membrane-induced enhancement of secretory activity was potentiated by dihydrotestosterone (DHT) and prostate stromal cell conditioned medium. Morphological studies showed that cells plated on basement membrane formed organoid-like clusters and maintained several aspects of differentiated epithelium including abundant secretory vesicles, microvilli, and desmosomes with associated cytoskeletal elements. Cultivation of epithelial cells on basement membrane components also suppressed the expression of vimentin, a mesenchymal intermediate filament polypeptide. However, cytokeratin expression was abnormal in cells grown on either surface. These results indicate that the differentiated properties of prostatic epithelial cells are promoted by cultivation on reconstituted basement membrane in the presence of DHT and stromal cell conditioned medium.

Markedly elevated maternal serum alpha-fetoprotein associated with a normal fetus and choriocarcinoma of the placenta.

Determination of maternal serum alpha-fetoprotein (MSAFP) has become an important screening test for a variety of fetal and maternal abnormalities. A 33-year-old multiparous white woman had a markedly elevated MSAFP level (140 multiples of the median). Extensive antepartum work-up for fetal anomalies, fetal-maternal transfusion, or maternal etiology revealed no explanation. The patient subsequently delivered a healthy male infant. Pathologic examination of the placenta demonstrated a small, discrete area of choriocarcinoma. Computed tomography showed a solitary pulmonary metastasis. Because the patient did not desire future pregnancies, a total abdominal hysterectomy was performed, followed by four courses of EMA-CO chemotherapy. Her serum hCG levels subsequently became undetectable. Choriocarcinoma of the placenta must be considered in the differential diagnosis of an otherwise unexplained elevated MSAFP level.