BRCA2 alteration is important in clear cell carcinoma of the ovary.

BRCA2 has been shown to play a significant role in hereditary ovarian carcinoma. Several cases of clear cell carcinoma (CCC) of the ovary containing BRCA2 mutations have been identified. We hypothesize that sequence variants of the BRCA2 gene are common in CCC of the ovary. Multiple methods were utilized to detect BRCA2 genetic alterations in a cohort of 13 ovarian CCC. These included an LOH analysis for copy number, real-time and methylation-specific polymerase chain reaction (PCR) to probe for BRCA2 promoter methylation, in addition to protein truncation testing (PTT) gel screening for nonsense BRCA2 mutations, and finally direct gene sequencing to either confirm the nonsense mutations or to detect candidate missense mutations in the remaining tumor samples. Whenever a sequence variation was detected in a tumor sample, the corresponding region was sequenced from a blood sample to determine germline status. Seven BRCA2 sequence variations were identified in 6 of the 13 CCC (46%); three tumors contained an alteration in BRCA2 copy number. Only one subject carried a germline sequence variation that might alter BRCA2 function despite the fact that a family history of breast, ovarian or colon cancer was common in this population. The 5-year disease-specific survival probability for patients with a BRCA2 alteration is 87.5%, compared to only 40% for those patients without a BRCA2 alteration (p = 0.39). Alterations in BRCA2 gene sequence, copy number, or expression are extremely common in CCC and may contribute to a paradoxical better clinical outcome.

Tunneled central venous catheters in a gynecologic oncology service: operative and short-term complications.

PURPOSE: To determine the difference in the immediate complication rate between placement of long-term central venous catheters (LTCVCs) by the percutaneous versus jugular venous cutdown method. METHOD: Case lists were examined to determine the number of LTCVCs placed during the designated time period. Medical records, operative reports, and chest roentgenograms were examined to extract pertinent information. Immediate complications included complications occurring in the operating room until 30 days postoperatively. Complications included misplacement of the catheter requiring an adjustment or a repeat procedure, pneumothorax, hydrothorax, or hemothorax, operative site or tunnel infection, and line migration requiring removal. RESULTS: Five hundred and one patients had LTCVCs placed during the period of this study. This included 399 totally implantable venous access devices (TIVADs) and 102 free access venous access devices (FAVADs) with 163 placed percutaneously into subclavian veins and 338 placed by cutdown into jugular veins. There was a significant increased risk in the overall immediate complication rate for the percutaneous placement compared to venous cutdown (p < 0.001). Also, pneumothorax was more common with the percutaneous approach compared to the venous cutdown approach (p < 0.001). CONCLUSIONS: Immediate complications, especially pneumothorax, were more common when placing catheters by the percutaneous approach as compared to the venous cutdown approach.

E-cadherin is a novel transcriptional target of the KLF6 tumor suppressor.

The tumor suppressor KLF6 is a member of the Krüppel-like family of transcription factors, which has been implicated in the pathogenesis of several human carcinomas. Uncovering the transcriptional targets relevant for its tumorigenic properties, including cellular proliferation and invasion, will be essential to understanding possible mechanisms by which KLF6 and its antagonistic splice form, KLF6-SV1, regulate this development. To begin defining possible metastatic-related pathways, we analysed the effect of KLF6 dysregulation on a recognized suppressor of cellular invasion, E-cadherin. Targeted KLF6 reduction in an ovarian cancer cell line, SKOV-3, resulted in a 50% reduction of E-cadherin expression (P<0.01) and conversely, KLF6-SV1 silencing upregulated E-cadherin approximately fivefold (P<0.0001). These changes resulted from KLF6 directly transactivating the E-cadherin promoter as demonstrated by luciferase promoter assay and chromatin immunoprecipitation (ChIP). KLF6-mediated changes in E-cadherin levels were accompanied by downstream changes in both the subcellular localization of beta-catenin and c-myc expression levels. Moreover, and consistent with these experimental findings, patient-derived epithelial ovarian tumors with low KLF6 and high KLF6-SV1 expression ratios had significantly decreased E-cadherin expression (P<0.0001). These combined findings highlight the E-cadherin pathway as a novel and functionally important mediator by which changes in KLF6 and KLF6-SV1 can directly alter ovarian tumor invasion and metastasis.

Association between nonrandom X-chromosome inactivation and BRCA1 mutation in germline DNA of patients with ovarian cancer.

BACKGROUND: Most human female cells contain two X chromosomes, only one of which is active. The process of X-chromosome inactivation, which occurs early in development, is usually random, producing tissues with equal mixtures of cells having active X chromosomes of either maternal or paternal origin. However, nonrandom inactivation may occur in a subset of females. If a tumor suppressor gene were located on the X chromosome and if females with a germline mutation in one copy of that suppressor gene experienced nonrandom X-chromosome inactivation, then some or all of the tissues of such women might lack the wild-type suppressor gene function. This scenario could represent a previously unrecognized mechanism for development of hereditary cancers. We investigated whether such a mechanism might contribute to the development of hereditary ovarian cancers. METHODS: Patterns of X-chromosome inactivation were determined by means of polymerase chain reaction amplification of the CAG-nucleotide repeat of the androgen receptor (AR) gene after methylation-sensitive restriction endonuclease digestion of blood mononuclear cell DNA from patients with invasive (n = 213) or borderline (n = 44) ovarian cancer and control subjects without a personal or family history of cancer (n = 50). BRCA1 gene status was determined by means of single-strand conformational polymorphism analysis and DNA sequencing. All statistical tests were two-sided. RESULTS AND CONCLUSIONS: Among individuals informative for the AR locus, nonrandom X-chromosome inactivation was found in the DNA of 53% of those with invasive cancer versus 28% of those with borderline cancer (P = .005) and 33% of healthy control subjects (P = .016). Nonrandom X-chromosome inactivation can be a heritable trait. Nine of 11 AR-informative carriers of germline BRCA1 mutations demonstrated nonrandom X-chromosome inactivation (.0002 < P < .008, for simultaneous occurrence of both). IMPLICATIONS: Nonrandom X-chromosome inactivation may be a predisposing factor for the development of invasive, but not borderline, ovarian cancer.

Ovarian cancer genomic instability correlates with p53 frameshift mutations.

We hypothesize that genomic instability plays an important role in causing specific types of p53 mutations in ovarian cancer. To test this hypothesis, 78 tumors were analyzed for p53 mutations with SSCP analysis of the entire open reading frame. At the same time, alterations in 10 microsatellite loci including di-, tri-, and tetranucleotide repeats were evaluated. Fourteen (26%) of all mutations were insertion/deletion mutations. All insertion/deletion mutations were associated with one of the following features: runs of purines or pyrimidines, repeats of short sequences, or palindromes. There was a strong association of generalized microsatellite instability with p53 in contrast to tumors with other types of mutations or wild-type p53 (P = 0.007). These characteristic p53 mutations appear to be caused by generalized genomic instability rather than to be the direct cause of genomic instability. These findings suggest the existence of additional novel DNA repair genes important to the carcinogenic process.

Application of the National Cancer Institute international criteria for determination of microsatellite instability in ovarian cancer.

Recently, the National Cancer Institute (NCI) established criteria for determination of microsatellite instability (MSI) in colorectal tumors. Although the best panel of markers for ovarian tumors is not known, we evaluated epithelial ovarian cancers for MSI based on the NCI recommendations. One hundred and nine ovarian tumors were analyzed for MSI by gel analysis of paired germ-line and tumor DNA. PCR amplification was performed using the panel of five microsatellite markers recommended by the NCI (BAT25, BAT26, D5S346, D2S123, and D17S250) and nine additional markers picked based on their genomic location (NME1, D10S197, D11S904, D13S175, DXS981, DXS6800, DXS6807, AR, and D3S1611). Tumors were characterized on the basis of: high-frequency MSI (MSI-H) if two or more of the five NCI markers showed instability or there was instability at 30% or more of all markers tested; or low-frequency MSI (MSI-L) if only one of the five NCI markers showed instability or <30% of all of the markers. All of the other tumors were considered microsatellite stable. On the basis of the NCI markers, 12 (11%) tumors demonstrated MSI-H, and 8 (7%) additional tumors had MSI-L. When all of the 14 markers were considered together, 13 (12%) tumors demonstrated MSI-H (based on 30% or more unstable loci), and 26 (24%) tumors had MSI-L. A single tumor identified to have MSI-H based upon all of the markers tested would have been classified as MSI-L based upon the NCI markers alone. Inclusion of an additional dinucleotide marker (NME1) to the NCI panel allowed detection of all of the tumors with MSI-H using only six markers. MSI-H occurs in approximately 12% of invasive ovarian tumors. For optimal detection of microsatellite instability in ovarian cancer, an additional marker (NME1) may be required, along with the five recommended by the NCI.

Genomic instability in ovarian cancer: a reassessment using an arbitrarily primed polymerase chain reaction.

Traditional polymerase chain reaction (PCR) amplification of multiple microsatellite markers to detect microsatellite instability (MI) is labor intensive and may be marker dependent. An arbitrarily primed polymerase chain reaction (AP-PCR) is a modification of PCR that generates a genomic DNA fingerprint using a single, arbitrarily chosen primer which is useful in the detection of somatic genetic alterations. We hypothesize that AP-PCR of an AluI DNA restriction digest, which we term Alu/AP-PCR, identifies genomic instability as well. In order to test this hypothesis, we correlated Alu/AP-PCR fingerprints with analyses of traditional PCR amplified microsatellite markers using paired germline and tumor DNA samples obtained from 68 patients with ovarian cancer. The microsatellite markers tested included dinucleotide, trinucleotide, and tetranucleotide repeats. We found that MI is more common in ovarian cancer than previously thought. We estimate a minimum incidence of MI at 37% based on the 10 traditional markers we tested, to an incidence of 53% based upon our Alu/AP-PCR analysis. All cases of MI were associated with an abnormal Alu/AP-PCR banding pattern. Both MI, detected by polymorphic markers (P=0.03), and an abnormal Alu/AP-PCR pattern (P=0.01) were significantly associated with the occurrence of a second primary malignancy in the same patient. In addition, abnormal Alu/AP-PCR patterns were associated with higher grade lesions (P=0.02), and family history of cancer (P=0.009). These findings suggest: (1) MI may play an important role in ovarian carcinogenesis, and (2) Alu/AP-PCR is a novel technique for identification of genomic instability.

An abundance of p53 null mutations in ovarian carcinoma.

Ovarian cancers from 64 midwestern US women were screened for p53 dysfunction both by immunohistochemical staining (IHCS) and single strand conformation polymorphism (SSCP) analysis of the entire open reading frame (ORF). Forty SSCP abnormalities in 39 tumors included nine deletion, one insertion, two splice junction, two nonsense, one silent and 25 missense mutations were confirmed by direct genomic sequencing. Eight of the insertion/deletion defects may have occurred due to slippage during the course of DNA replication. This observation suggests that genomic instability may play an important role in ovarian carcinogenesis. Fifteen percent of the mutations encountered were located outside exons 5-9 and four of these were null. The sensitivity of IHCS was 96% for missense mutations but only 14% for null mutations. This contrasted with 100% sensitivity of the SSCP screening methodology. The 21% overall incidence of null mutations in the present study far exceeds the reported 6.8% incidence in the world literature (P=0.0003). Explanations for this difference include: (1) our complete analysis of the entire ORF of the p53 gene; (2) the tendency of others to rely upon IHCS to screen tumors prior to mutation analysis; and (3) environmental or endogenous genetic influences.

Distant metastases in ovarian cancer: association with p53 mutations.

Distant metastases are unusual occurrences at presentation and during the progression of epithelial ovarian cancer. There are no good clinical predictors of this phenomenon. Because p53 dysfunction is common in ovarian cancer, we chose to investigate whether specific types of mutations predicted a predisposition to distant metastasis. We hypothesized that the complete absence of intact p53 protein as seen with p53 null mutations may be associated with an enhanced tendency to develop distant metastatic disease. The complete coding sequence of 130 tumor DNA samples was screened for p53 mutations by single-strand conformational polymorphism analysis. Abnormal single-strand conformational polymorphism findings were correlated with the specific DNA sequence abnormalities and outcome. Ninety-four (72%) tumors carried p53 mutations. Sixty-two were missense mutations, and 32 were null mutations (6 nonsense mutations, 23 frameshift mutations, and 3 splice-site mutations). Twenty-eight patients were found to have distant metastases (pericardium, brain, parenchymal liver, spleen, or lung) either at presentation or during the course of their treatment. Distant metastases were nearly 8-fold more common in patients whose tumors carried a null mutation (66%) than in those with either missense mutations (8%) or wild-type p53 (8%; P<0.001). When a null mutation was present, 25% of the tumors were associated with distant metastases at initial diagnosis. No individual with wild-type p53 or a missense mutation in the tumor presented with distant metastasis. Tumors with null mutations were more likely to be associated with lymph node metastasis (P = 0.003), advanced stage (stage III/IV; P<0.001) and high grade (grade II/III; P<0.001), at presentation. These tumors progressed with distant metastases more swiftly than did tumors with either missense mutations (mean, 1.18 versus 2.71 years; P = 0.04) or wild-type p53 (3.57 years; P = 0.015). In contrast to the popular dogma, distant metastases in ovarian cancer do not necessarily result from prolonged treatment of disease. They may be predicted to occur early in the disease course due to a specific molecular genetic abnormality: null mutation of the p53 tumor suppressor gene. These findings need to be carefully considered when choosing between regional versus systemic treatment modalities.

The p53 mutational spectrum associated with BRCA1 mutant ovarian cancer.

PURPOSE: Cancer-specific p53 mutational spectra have been identified. Data from murine models and human BRCA1-related hereditary breast cancers suggest that both unique and specific BRCA1-associated p53 mutations may be found in BRCA1-related ovarian cancers. EXPERIMENTAL DESIGN: The p53 mutational spectrum from ovarian cancers containing either somatic or germ-line BRCA1 mutations was compared with that of sporadic ovarian cancers defined as those diagnosed with a negative family history for breast/ovarian cancer in a three-generation pedigree. Tumor DNA was screened over exons 2-11 of the p53 gene by the PCR and single-strand confirmation polymorphism analysis of the amplimers. Cycle-based DNA sequencing from separate reactions was used to confirm p53 mutations. RESULTS: p53 gene mutations were detected in 42 of 86 sporadic ovarian cancers, compared with 13 of 15 cancers with somatic BRCA1 mutations (P = 0.007) and 16 of 20 cancers with germ-line BRCA1 mutations (P = 0.01). p53 null mutations were found in 31.4% of BRCA1 mutant cancers, compared with only 9.3% of the sporadic cancers (P = 0.002). The p53 mutational spectrum of germ-line BRCA1-related cancers was shifted toward transversions, frameshifts, and non-CpG transitions relative to the spectrum of sporadic ovarian cancers. Thirty-three unique ovarian cancer p53 mutations were sequenced. However, the specific p53 mutations in the BRCA1 mutant cancers were no more unique to this cohort than the p53 mutations of the sporadic cancers. CONCLUSIONS: Ovarian cancers containing somatic or germ-line BRCA1 mutations are uniformly accompanied by p53 dysfunction. This finding offers additional support to observations regarding the importance of p53/BRCA1 interactions in ovarian carcinogenesis.

Ovarian cancer BRCA1 mutation detection: Protein truncation test (PTT) outperforms single strand conformation polymorphism analysis (SSCP).

Recent studies have shown that the BRCA1 tumor suppressor gene plays a role in the development of both hereditary and sporadic ovarian cancer. Since several different mechanisms may give rise to tumor gene defects, a better understanding of these mechanisms may identify BRCA1 as an attractive therapeutic target in ovarian cancer. Sequencing this large gene is not practical on a population-wide basis. The optimal screening strategy is yet to be determined. The purpose of our study is to compare two common screening techniques: the protein truncation test (PTT) and single strand conformational polymorphism analysis (SSCP). Ninety-four patients with epithelial ovarian cancer and available snap-frozen tissue were screened for BRCA1 mutations by both PTT (five individual PCR reactions with complete translation of the product in the TNT System (Promega, Madison, WI)) and SSCP (41 individual PCR reactions covering the entire coding sequence). All abnormal results were confirmed by sequencing. A paired peripheral blood DNA sample was utilized to determine if the sequence abnormality was a germline mutation. Twenty-three mutations in BRCA1 were found in 22 patients (14 germline, eight somatic, one unknown) including four novel mutations: E489X, 3558delT, 3871delGTCT, del exon 7-10. Although the predictive value of a negative test was close for the two methods (PTT 99.1%, SSCP 99.8%), the comparison of positive predictive value overwhelmingly favored PTT (100.0%, vs. 26.4%, respectively). The specificity for PTT was 100.0% while the sensitivity was 82.6%. While for SSCP, the specificity was 99.0% and the sensitivity was only 60.9%. The concordance rate for the two screening tests was 88.9%. Only SSCP can detect missense mutations. PTT is a superior screening test for truncating BRCA1 mutations that are expected to be of clinical significance.

Cyclosporin A reverses chemoresistance in patients with gynecologic malignancies.

Multidrug resistance is a major obstacle in successful systemic therapy of gynecologic malignancies. The objectives of this study are to evaluate the activity of cyclosporin A used to overcome drug resistance in a variety of gynecologic malignancies. Forty women (29 with ovarian cancer, 7 with uterine cancer, 3 with cervical cancer, and 1 with choriocarcinoma) were treated with cyclosporin A, 4 mg/kg intravenously, 6 hours before and 18 hours after the specific chemotherapeutic agent, to which the tumor had developed drug resistance. All patients had shown resistance to the chemotherapy agent used in combination with cyclosporin A. All patients had been heavily pretreated (mean, 2.8 previous chemotherapy regimens). Overall, among 38 available patients with gynecologic malignancies, a 29% objective response rate was observed. Twenty-six (65%) of all patients received three or more cycles of cyclosporin A. There was a 25% response rate for patients with ovarian cancer patients and 50% for those with uterine cancer. There were no responses among the three patients with cervical cancer, and the patient with choriocarcinoma had a complete response. All patients were evaluable for toxicity. Leukopenia and nausea were the most common toxic reactions, but in most cases they were transient, and only three patients required a treatment delay. The most common grade 3 or 4 toxicity was thrombocytopenia, which was observed in 22% of the patients. Cyclosporin A is well tolerated and has significant potential for reversal of chemoresistance in heavily pretreated patients with ovarian and uterine malignancies.

Herman Beerman lecture. Mechanisms of steroid hormone action.

PIP: The molecular biology of steroid hormone action is reviewed. Topics discussed include the chick oviduct system as a model for exploring the effects of steroid hormones, the nature of steroid hormone receptors, the nuclear uptake of receptor-hormone complexes, nuclear retention of the receptor-hormone complex, the initiation of RNA synthesis by steroid hormones, the synthesis, modification, and export of messenger RNA, and translation of mRNA. It has been possible to induce ovalbumin mRNA synthesis in vitro by combining purified steroid hormone-receptor complexes with RNA polymerase, interphase chromosomes, and necessary substrates. A similar effect is observed in vivo with progesterone treatment. It is suggested that steroid hormone receptors act directly on the cell's genetic apparatus to promote gene expression.^ieng

The glutathione S-transferase M1 genotype in ovarian cancer.

Glutathione S-transferase mu-1 (GSTM1) is a polymorphic member of the mu class gene family of the glutathione S-transferases. Individuals who are GSTM1 null have increased susceptibility to lung and colon cancer. We hypothesized that: (a) GSTM1 null individuals might also be at increased risk for development of ovarian cancer; and (b) the GSTM1 genotype would influence response to chemotherapy. One hundred and forty-six individuals with invasive epithelial ovarian cancer were genotyped using a three-primer PCR reaction specific for the GSTM1 gene and an internal control glutathione S-transferase mu-4 (GSTM4). The products were analyzed on agarose gels. Healthy individuals without a family history of ovarian, breast, or colon cancer served as unmatched controls (n = 80). The results show that age at diagnosis, histological type, and stage of ovarian cancer were all independent of GSTM1 genotype. The frequency of the GSTM1 null genotype in the ovarian cancer cohort was similar to that in the control population, 51% versus 58%, P > 0.05. Likewise, median survival for individuals with advanced stage ovarian cancer was independent of GSTM1 genotype. We concluded that the GSTM1 null genotype does not increase ovarian cancer risk. These findings suggest that GSTM1 does not play a significant role in detoxifying environmental factors that influence ovarian carcinogenesis and does not play an important role in the resistance of ovarian cancer to chemotherapy.

The influence of the p53 codon 72 polymorphism on ovarian carcinogenesis and prognosis.

The frequency of dysfunction of the p53 tumor suppressor gene in cancer has made the concept of gene replacement therapy with wild-type p53 an attractive strategy. Codon 72 of the p53 gene is highly polymorphic with a reported arginine/proline allelotype frequency of 0.65/0.35 for Caucasians and a reversal of this ratio in African-Americans. Ovarian cancer is more common and less aggressive in Caucasians. The arginine and proline alleles have different biochemical properties. Thus, we have hypothesized that these alleles may also have different biologic properties that could make one superior to the other for gene replacement therapy. To test this hypothesis in vivo, we investigated the prevalence of each allelotype in a population of 190 Midwestern American women with ovarian cancer and 52 healthy controls without a family history of cancer. We have found that: (1) the heterozygous arginine/proline allelotype is more common in probands with borderline cancers than in probands with invasive cancers (P = .0001) or healthy controls (P = .005); (2) despite a survival advantage (P = .006), probands homozygous for the arginine allele developed ovarian cancer at an earlier age (P = .01); (3) the frequency of tumor p53 mutations was independent of the germline p53 allelotype, but (4) when a loss of heterozygosity occurred in probands with invasive disease, the proline allele was lost preferentially (P = .002), and (5) any tumor which retained a proline allele was more prone to mutation (P = .04) than a tumor without a proline allele. Our results suggest that variation in the p53 codon 72 allelotype is an example of an intermediate risk polymorphism which interacts with epigenetic factors to play a role in ovarian carcinogenesis and may differentially influence cellular DNA repair and apoptotic pathways. These findings may have important ramifications in the choice of wild-type p53 genotype for gene replacement therapy of ovarian cancer.

The use of laminarias for osmotic dilation of the cervix in gynecological brachytherapy applications.

PURPOSE: Osmotic dilators (laminarias) have been used for gradual nontraumatic dilation of the cervical canal for various intrauterine procedures; however, this technique has not been well accepted in gynecological brachytherapy. The purpose of this study was to evaluate the efficacy of osmotic cervical dilation for brachytherapy in gynecologic cancer patients, without the use of general/regional anesthesia, and to assess patient tolerance, complications, and outcome. METHODS AND MATERIALS: Thirteen brachytherapy procedures were performed in 6 patients with clinical Stages I and II endometrial (5) and Stage IB cervical cancer (1), who were unable to tolerate general/regional anesthesia because of severe medical problems. An osmotic dilator (synthetic laminaria) was inserted into the cervical os 10-12 h before each brachytherapy procedure and removed just before the procedure. Standard Fletcher-Suit-Delclos tandem insertions with vaginal colpostats or cylinders were then performed. Degree of cervical dilation, patient discomfort, procedure time, intra- and postoperative complications were recorded, and local control and survival were assessed. Median follow-up was 31 months (range: 8-35 months). RESULTS: The diameter of the dilated cervical os after laminaria removal was adequate (> or = 5 mm) for tandem insertion, and no additional mechanical dilation was required in all but one procedure (1 of 13). All procedures were performed without general/regional anesthesia. The mean duration of the procedures was 44 min (range, 20-60 min). Discomfort was minimal in all cases. There were no intra- or postoperative complications. All patients maintained local control until death (1 of metastatic disease, 2 of intercurrent disease) or last follow-up (2 with no evidence of disease, 1 alive with metastatic disease). CONCLUSION: This preliminary study suggests that osmotic cervical dilation with a synthetic laminaria is a useful technique to facilitate intrauterine tandem insertion in patients who cannot tolerate general/regional anesthesia. This technique may reduce treatment-associated morbidity, shorten procedure time, and allow the delivery of adequate radiation therapy in this uncommon but challenging patient population.

Tumor perfusion studies using fast magnetic resonance imaging technique in advanced cervical cancer: a new noninvasive predictive assay.

PURPOSE: This study investigated sequential changes in tumor blood supply using magnetic resonance (MR) perfusion imaging and assessed their significance in the prediction of outcome of patients with advanced cervical cancer. The purpose of this project was to devise a simple, noninvasive method to predict early signs of treatment failure in advanced cervical cancer treated with conventional radiation therapy. METHODS AND MATERIALS: Sixty-eight MR perfusion studies were performed prospectively in 17 patients with squamous carcinomas (14) and adenocarcinomas (3) of the cervix, Stages bulky IB (1), IIB (5), IIIA (1), IIIB (8), and IVA (1), and recurrent (1). Four sequential studies were obtained in each patient: immediately before radiation therapy (pretherapy), after a dose of 20-22 Gy/ approximately 2 weeks (early therapy), after a dose of 40-45 Gy/ approximately 4-5 weeks (midtherapy), and 4-6 weeks after completion of therapy (follow-up). Perfusion imaging of the tumor was obtained at 3-s intervals in the sagittal plane. A bolus of 0.1 mmol/kg of MR contrast material (gadoteridol) was injected intravenously 30 s after beginning image acquisition at a rate of 9 ml/s using a power injector. Time/signal-intensity curves to reflect the onset, slope, and relative signal intensity (rSI) of contrast enhancement in the tumor region were generated. Median follow-up was 8 months (range 3-18 months). RESULTS: Tumors with a higher tissue perfusion (rSI > or = 2.8) in the pretherapy and early therapy (20-22 Gy) studies had a lower incidence of local recurrence than those with a rSI of < 2.8, but this was not statistically significant (13% vs. 67%; p = 0.05). An increase in tumor perfusion early during therapy (20-22 Gy), particularly to an rSI of > or = 2.8, was the strongest predictor of local recurrence (0% vs. 78%; p = 0.002). However, pelvic examination during early therapy (20-22 Gy) commonly showed no appreciable tumor regression. The slope of the time/signal-intensity curve obtained before and during radiation therapy also correlated with local recurrence. Follow-up perfusion studies did not provide information to predict recurrence. CONCLUSION: These preliminary results suggest that two simple MR perfusion studies before and early in therapy can offer important information on treatment outcome within the first 2 weeks of radiation therapy before response is evident by clinical examination. High tumor perfusion before therapy and increasing or persistent high perfusion early during the course of therapy appear to be favorable signs. High perfusion suggests a high blood and oxygen supply to the tumor. The increase in tumor perfusion seen in some patients early during radiation therapy suggests improved oxygenation of previously hypoxic cells following early cell kill. Radiation therapy is more effective in eradicating these tumors, resulting in improved local control. Our technique may be helpful in identifying early-while more aggressive therapy can still be implemented-those patients who respond poorly to conventional radiation therapy.

Drug resistance in ovarian cancer: from the laboratory to the clinic.

OBJECTIVE: To provide a review of the basic mechanisms of drug resistance in ovarian cancer and novel strategies to modulate drug resistance for the general obstetrician-gynecologist. DATA SOURCES: Relevant articles published through December 1996 were identified using the MEDLINE data base. Additional sources were found by cross-referencing. METHODS OF STUDY SELECTION: Publications identified by the search were reviewed and evaluated critically for their relevance to drug resistance in ovarian cancer. TABULATION, INTEGRATION, AND RESULTS: Each reference was reviewed for its contribution to the knowledge regarding mechanisms of chemotherapy resistance in ovarian cancer or strategies to modulate resistance. CONCLUSION: Ovarian cancer patients have high response rates to initial chemotherapy after cytoreductive surgery. However, most will develop resistance to chemotherapy during the course of their treatment. There are multiple mechanisms resulting in drug resistance. Strategies to modulate drug resistance include dose intensity, various pharmacologic agents, and gene therapy.

Computed tomography in endometrial carcinoma.

OBJECTIVE: To determine the value of computed tomography (CT) scans for preoperatively detecting extrauterine-nodal disease and postoperative recurrent disease in patients with endometrial cancer. METHODS: We reviewed records of 702 women with primary endometrial carcinoma that was diagnosed between 1979 and 1993. Preoperative CT findings were compared with pathologic findings to assess nodal disease. The yield of postoperative CT was reviewed in clinically suspicious and routine settings. RESULTS: Among 492 women eligible for analysis, 178 (36%) had a total 326 CT scans. Among 56 women who had preoperative CT scans and lymph node samplings, positive and negative predictive values for nodal involvement were 50% and 94%, respectively, and sensitivity and specificity were 57% and 92%, respectively. Preoperative CT findings altered treatment plans in only six patients (8%). Forty-five asymptomatic women had 73 routine CT scans, and recurrence was diagnosed by CT in only two (4.4%). Thirty-seven women had CT scans for suspicion of recurrence, which was confirmed in 17 (46%). Kaplan-Meyer analysis showed no survival advantage in women with subclinical recurrences diagnosed by CT scan. CONCLUSION: Routine preoperative CT scanning rarely alters treatment and is a poor predictor of nodal disease. Computed tomography in the postoperative period might be helpful for detection and follow-up of recurrent disease, but there was no difference in survival when subclinical recurrence was found by CT. Thus, CT scanning of any woman with endometrial cancer should be discouraged unless it is to evaluate symptoms.

Indiana pouch continent urinary reservoir in patients with previous pelvic irradiation.

Little information exists on the use of continent urinary reservoirs in patients with previous pelvic irradiation. We report the use of the Indiana pouch urinary reservoir in ten women with a history of pelvic irradiation for cervical cancer, of whom eight underwent a total pelvic exenteration for recurrent pelvic tumor and two had diversion for radiation-induced vesicovaginal fistula. All ten women achieved daytime continence, with a median time between catheterizations of 4.5 hours and a median pouch capacity of 500 mL. There was no evidence of leakage from the reservoir or significant ureteral reflux or obstruction on postoperative radiographic evaluation. No patient has required reoperation or had significant postoperative complications with the technique described.