Disseminating universal genetic testing to a diverse, indigent patient population at a county hospital gynecologic oncology clinic.

OBJECTIVE: The universal genetic testing initiative (UGTI) is a quality improvement effort to increase rates of guideline-based genetic counseling (GC) and genetic testing (GT) of patients with potentially hereditary cancers. The UGTI was disseminated to a county hospital gynecologic oncology clinic that serves a diverse, indigent patient population. METHODS: Using the Model for Improvement quality improvement framework, interventions including integrated GC, clinic tracking, assisted GC referrals, and provider education were tested over 26 months. A retrospective data review included patients with high-grade, non-mucinous epithelial ovarian, fallopian tube, and primary peritoneal cancers (HGOC) and endometrial cancers (EC) diagnosed between 9/1/12-8/31/16. Statistical analyses were performed to describe the population and to evaluate rates of recommendation and use of immunohistochemistry tumor testing (IHC), GC, and GT. RESULTS: A cohort of 241 patients (57 HGOC, 184 EC) were included. At the conclusion of the study 84.2% of HGOC patients were referred for GC, 89.6% (43/48) completed GC, and 90.7% (39/43) completed GT. Of EC patients, 81.0% were recommended to have IHC and 62.4% (93/149) completed IHC. Patients with HGOC diagnosed during dissemination of UGTI were significantly more likely to receive a recommendation for GC (p = 0.02) and to complete GT (p = 0.03) than those diagnosed before UGTI. Patients with EC were significantly more likely to complete IHC if diagnosed after UGTI than those diagnosed prior to dissemination (p < 0.001). CONCLUSIONS: The UGTI can be adapted to increase use of guideline-based cancer genetics services in a diverse, indigent, gynecologic cancer patient population.

ISG15 Promotes ERK1 ISGylation, CD8+ T Cell Activation and Suppresses Ovarian Cancer Progression.

Increased number of tumor-infiltrating CD8+ lymphocytes is associated with improved survival in patients with advanced stage high grade serous ovarian cancer (HGSOC) but the underlying molecular mechanism has not been thoroughly explored. Using transcriptome profiling of microdissected HGSOC tissue with high and low CD8+ lymphocyte count and subsequent validation studies, we demonstrated that significantly increased ISG15 (Interferon-stimulated gene 15) expression in HGSOC was associated with high CD8+ lymphocyte count and with the improvement in median overall survival in both univariate and multivariate analyses. Further functional studies showed that endogenous and exogenous ISG15 suppressed ovarian cancer progression through ISGylation of ERK in HGSOC, and activation of NK cells and CD8+ T lymphocytes. These data suggest that the development of treatment strategies based on up-regulating ISG15 in ovarian cancer cells or increased circulating ISG15 in ovarian cancer patients is warranted.

2013 HIPAA Changes Provide Opportunities and Challenges for Researchers: Perspectives from a Cancer Center.

In 2013, the U.S. Department of Health and Human Services modified the Health Insurance Portability and Accountability Act Privacy Rule to "strengthen privacy and security protections" while "improving workability and effectiveness to increase flexibility for and decrease burden on regulated entities." In this article, we attempt to translate these generalized goals into the real-world implications of these changes. Under the new rules, researchers can obtain participants' permission to use their protected health information for more research activities with a single, upfront authorization (thereby reducing paperwork for participants, researchers, and institutional review boards) while providing potential participants with more information upon which to base their decisions about participation. The combined authorizations can be used in clinical trials and their optional substudies and in stand-alone biospecimen-banking research that includes authorization to permit future research use. We also suggest best practices for taking advantage of the flexibility offered by the new rules while maintaining strong privacy protections for human subjects.

Is conflict of interest becoming a challenge for institution-based institutional review boards?

Expansion of business relationships between academic institutions and their leaders and industry have become a reality, whereas media attention regarding conflict of interest (COI) at academic institutions has raised concerns about possible erosion of public trust. The Institutional Review Board (IRB) should collaborate with institutional COI committees to ensure that research with human subjects is in compliance with various applicable federal regulations. The IRB and COI committee should take additional independent action as necessary under their separate mandates to protect the welfare, safety, and rights of human subjects and to include limits on protocols affected by significant financial interests of the institution or its decision makers. If unable to review research due to an intrainstitutional conflict, the local IRB should consider transferring the study review and oversight to an external unaffiliated institutional or central IRB. A process for involvement of an executive institutional IRB is proposed.

Plasmacytoid dendritic cells promote immunosuppression in ovarian cancer via ICOS costimulation of Foxp3(+) T-regulatory cells.

Epithelial ovarian cancer (EOC) is the fifth most common cause of cancer death among women. Despite its immunogenicity, effective antitumor responses are limited, due, in part, to the presence of forkhead box protein 3-positive (Foxp3(+)) T regulatory (Treg) cells in the tumor microenvironment. However, the mechanisms that regulate the accumulation and the suppressive function of these Foxp3(+) Treg cells are poorly understood. Here, we found that the majority of Foxp3(+) Treg cells accumulating in the tumor microenvironment of EOCs belong to the subset of Foxp3(+) Treg cells expressing inducible costimulator (ICOS). The expansion and the suppressive function of these cells were strictly dependent on ICOS-L costimulation provided by tumor plasmacytoid dendritic cells (pDC). Accordingly, ICOS(+) Foxp3(+) Treg cells were found to localize in close vicinity of tumor pDCs, and their number directly correlated with the numbers of pDCs in the tumors. Furthermore, pDCs and ICOS(+) Foxp3(+) Treg cells were found to be strong predictors for disease progression in patients with ovarian cancer, with ICOS(+) Treg cell subset being a stronger predictor than total Foxp3(+) Treg cells. These findings suggest an essential role for pDCs and ICOS-L in immunosuppression mediated by ICOS(+) Foxp3(+) Treg cells, leading to tumor progression in ovarian cancer.

MODELING DEPENDENT GENE EXPRESSION.

In this paper we propose a Bayesian approach for inference about dependence of high throughput gene expression. Our goals are to use prior knowledge about pathways to anchor inference about dependence among genes; to account for this dependence while making inferences about differences in mean expression across phenotypes; and to explore differences in the dependence itself across phenotypes. Useful features of the proposed approach are a model-based parsimonious representation of expression as an ordinal outcome, a novel and flexible representation of prior information on the nature of dependencies, and the use of a coherent probability model over both the structure and strength of the dependencies of interest. We evaluate our approach through simulations and in the analysis of data on expression of genes in the Complement and Coagulation Cascade pathway in ovarian cancer.

Nearly 30 Years of Treatment for Recurrent Granulosa Cell Tumor of the Ovary: A Case Report and Review of the Literature.

A 30-year-old woman was diagnosed with a stage IA granulosa cell tumor (GCT) of the ovary in 1979. Following removal of the adnexal mass and complete surgical staging, she remained disease-free for 12 years. In 1991 she underwent a resection of a retroperitoneal mass, confirmed to be a recurrent GCT. Despite adjuvant radiation treatment at the time of recurrence, the patient presented five years later with abdominal pain, and was found to have a second recurrence. Over the next 10 years the patient had multiple recurrences and progressive disease despite surgical resection, cytotoxic, hormonal and targeted chemotherapy treatments. In conclusion, there is no standard management for recurrent GCT of the ovary. We review this patient's treatment in the context of the current literature.

Differential expression of CD3zeta message and protein in tumor infiltrating lymphocytes from solid tumor specimens and malignant ascites from patients with ovarian carcinoma.

The expression of the CD3zeta subunit was investigated in fresh (uncultured) tumor-infiltrating lymphocytes (TILs) isolated from either solid tumor (ST) specimens or ascites (ASC) from patients with epithelial ovarian carcinoma (EOC). Western blot analysis of CD3zeta immunoprecipitates using anti-CD3zeta rabbit serum revealed that in 6 out of 6 patients with EOC, the CD3zeta protein was absent from ST-TILs. Immunoprecipitation with anti-phosphotyrosine monoclonal antibody (anti-PY20) from ST-TILs from one patient revealed bands co-migrating with the phosphorylated CD3zeta. CD3zeta protein was found to be expressed in only 1 out of 7 ST-TILs from patients with EOC. ASC-TILs were available in 5 of these patients and immunoprecipitation/Western blotting experiments using anti-CD3zeta rabbit serum revealed that CD3zeta protein was expressed in all 5. In addition, CD3zeta protein was expressed in 3 additional ASC-TIL specimens for which ST-TILs were not available. Therefore, the CD3zeta protein was expressed in ASC-TIL isolated from 8 out of 8 patients with EOC. CD3zeta protein was also expressed on peripheral blood mononuclear cells (PBMCs) from patients with EOC and from normal donors. RT-PCR studies of fresh ST-TIL specimens, using CD3zeta-specific primers, revealed that CD3zeta transcripts were absent from 13 out of 21 patients with EOC, down-regulated in 4 patients and present at levels comparable to those found in PBMCs in 4 other patients. In contrast, CD3delta transcripts were present at comparable levels in all specimens. Treatment with recombinant interleukin-2 (rIL-2) (600 IU/ml) restored the expression of CD3zeta protein and transcripts in cultured ST-TILs, whereas fresh ST-TILs did not express CD3zeta, in contrast to fresh ASC-TILs. These results demonstrate differential expression of CD3zeta in ST-TILs versus ASC-TILs in patients with EOC. CD3zeta transcripts and protein were found to be absent from most ST-TILs from patients with EOC, whereas they were expressed in ASC-TILs and PBMCs from such patients.

A phase II study of GM-CSF and rIFN-gamma1b plus carboplatin for the treatment of recurrent, platinum-sensitive ovarian, fallopian tube and primary peritoneal cancer.

OBJECTIVE: To evaluate the efficacy and toxicity of carboplatin, granulocyte-macrophage colony-stimulating factor (GM-CSF) and recombinant interferon gamma 1b (rIFN-gamma1b) in women with recurrent, platinum-sensitive ovarian, fallopian tube and primary peritoneal cancer. METHODS: In this phase II study, patients with recurrent, platinum-sensitive ovarian, fallopian tube or primary peritoneal cancer were treated with subcutaneous GM-CSF and rIFN-gamma1b before and after intravenous carboplatin until disease progression or unacceptable toxicity. All patients had measurable disease and a chemotherapy-free interval >6 months. Response was determined using RECIST criteria and CA 125 levels. RESULTS: Between 2003 and 2007, 59 patients received a median of 6 cycles of therapy (range, 1 to 13 cycles). Median age at enrollment was 61 years (range, 35 to 79 years). Median time to progression prior to enrollment was 11 months (range, 6 to 58 months). Of 54 patients evaluable for response, 9 (17%) had a complete response, 21 (39%) had a partial response, and 24 (44%) had progressive disease. The overall response rate was 56% (95% CI: 41% to 69%). With a median follow-up of 6.4 months, median time to progression was 6 months. Myeloid derived cells and platelets increased on day 9 of each chemotherapy cycle. The most common adverse effects were bone marrow suppression, carboplatin hypersensitivity, and fatigue. Responders reported improved quality of life. CONCLUSION: This pre and post-carboplatin cytokine regimen resulted in a reasonable response and a hematologic profile that could invite further evaluation of its components in the treatment of patients with ovarian cancer.

14-3-3 zeta protein secreted by tumor associated monocytes/macrophages from ascites of epithelial ovarian cancer patients.

Tumor associated monocytes/macrophages (MO/MA) are known contributors to the immune-inflammatory cell environment of advanced epithelial ovarian carcinoma (EOC). The secreted proteome of ascitic MO/MA was examined as an aid to the discovery of novel proteins in EOC that are likely to have biological relevance in the inflammatory pathways of EOC. Ascitic fluid MO/MA were isolated from EOC patients, grown short-term in serum-free media. MO/MA supernatants were analyzed for secreted proteins by HPLC fractionation followed by LC-tandem mass spectrometric analysis. The 14-3-3 zeta adaptor protein was identified in supernatants of three of three EOC patients but not in supernatants of buffy coat monocytes isolated from normal donors or the established monocyte cell line THP1. Moreover, 14-3-3 zeta was identified in ascitic fluids in eight of eight chemotherapy-naïve patients by both immunoblot and mass spectrometric analysis. Immunofluorescent staining for 14-3-3 zeta demonstrated expression of the protein on ascitic and peritumoral macrophages in EOC patients. 14-3-3 zeta was also expressed on endothelial cells in the peritumoral stroma and partially on tumor cells. Uptake of 14-3-3 zeta was observed in EOC cell lines co-cultured with the recombinant protein expressed in E. coli. It is demonstrated for the first time that the important adaptor protein 14-3-3 zeta is common to the secretome of ascitic MO/MA and the ascites of advanced EOC patients.

Placental-site trophoblastic tumors: a case of resistant pulmonary metastasis.

Background A 52-year-old woman whose last known pregnancy was 12 years before presentation was diagnosed with mixed trophoblastic tumor that included placental-site trophoblastic tumor, epithelioid trophoblastic tumor, and focal choriocarcinoma. There was no clear evidence of metastatic disease on initial evaluation. Investigations Histopathology, laboratory tests, immunohistochemistry, chest X-ray, CT scan of the chest, abdomen, and pelvis, fine-needle aspiration biopsy, PET-CT scan.Diagnosis Metastatic chemoresistant placental-site trophoblastic tumor positive for EGFR, VEGF receptor, and platelet-derived growth factor receptor. Management Abdominal hysterectomy, bilateral salpingo-oophorectomy, pelvic radiation, etoposide, methotrexate, actinomycin D/cyclophosphamide and vincristine chemotherapy, left thoracotomy with wedge resection, taxol, etoposide, cisplatin therapy, right thoracotomy with wedge resection.

Migration deficit in monocyte-macrophages in human ovarian cancer.

PURPOSE: To examine the migration responses of monocyte/macrophages (MO/MA) expressing complementary receptors to chemokines produced in the tumor environment of epithelial ovarian cancer (EOC). METHODS: We examined the expression of the chemokine receptors, CCR1, CCR5, and CXCR4, on EOC associated ascitic and blood MO/MA; their response to complementary chemokines in a MO/MA migration assay and the F-actin content in an actin polymerization assay. A validated cDNA microarray assay was then utilized to examine alterations in pathway genes that can be identified with cell migration. RESULTS: Ascitic and EOC blood MO/MA express CCR1, CCR5 and CXCR4, but differently. Cell surface expression levels for CCR1 and CCR5 were higher in ascites than that of normal blood in contrast to CXCR4 levels in ascitic MO/MA which were lower. EOC associated ascitic or blood MO/MA failed to migrate in response to the CC ligand RANTES and to the CXCR4 reactive chemokine, SDF1 (CXCL12). Ascitic and most EOC blood MO/MA also behaved differently from normal blood MO in the polymerization/depolymerization assay. A cDNA gene analysis of purified ascitic MO/MA demonstrated that a number of genes involved with chemokine production, focal adhesion, actin cytoskeletal function and leukocyte transendothelial migration were down-regulated in the ascitic MO/MA when compared to normal blood MO. Moreover, PBMC cDNA from EOC patients' blood also showed gene profiles similar to that of ascitic MO/MA. CONCLUSIONS: Defective migration and polymerization/depolymerization activity of MO/MA from EOC patients and a significant down-regulation of critical pathway genes suggest that other mechanisms might be involved in the accumulation of systemically derived MO at the tumor site of EOC patients.

Phase II study of intraperitoneal recombinant interleukin-12 (rhIL-12) in patients with peritoneal carcinomatosis (residual disease < 1 cm) associated with ovarian cancer or primary peritoneal carcinoma.

BACKGROUND: Pharmacokinetic advantages of intraperitoneal (IP) rhIL-12, tumor response to IP delivery of other cytokines as well as its potential anti-angiogenic effect provided the rationale for further evaluation of IPrhIL-12 in patients with persistent ovarian or peritoneal carcinoma. METHODS: A phase 2 multi-institutional trial (NCI Study #2251) of IP rIL-12 (300 nanogram/Kg weekly) was conducted in patients with ovarian carcinoma or primary peritoneal carcinoma. Patients treated with primary therapy for ovarian cancer who had no extraabdominal/parenchymal disease or bulky peritoneal disease were eligible. Four to 8 weeks from last chemotherapy, eligible patients underwent a laparotomy/laparoscopy. Patients with residual disease < or = 1 cm were registered for the treatment phase 2-5 weeks post surgery. The effect of IP rIL-12 on the expression of TNFalpha , INFalpha , IL-10, IP-10, IL-8, FGF, VEGF was also studied. RESULTS: Thirty-four patients were registered for the first screening phase of the study. Median age was 56.6 years (range: 31-71); 12 completed the second phase and were evaluable for response/toxicity. Performance scores of IL-12 treated patients were 0 (11 pts) and 1 (1 pt). There were no treatment related deaths, peritonitis or significant catheter related complications. Toxicities included grade 4 neutropenia (1), grade 3 fatigue (4), headache (2), myalgia (2), non-neutropenic fever (1), drug fever (1), back pain (1), and dizziness (1). The best response observed was SD. Two patients had SD and 9 had PD, and 1 was evaluable for toxicity only. Peritoneal fluid cytokine measurements demonstrated a > or = 3 fold relative increase post-rhIL-12: IFN-gamma, 5/5 pts; TNF-alpha , 1/5; IL-10, 4/5; IL-8, 5/5; and VEGF, 3/5. IP10 levels were increased in 5/5 patients. Cytokine response profiles suggest either NK or T-cell mediated effects of IP rhIL-12. Cytokine/chemokine results also suggest a pleiotropic response since proteins with potential for either anti-tumor (IFN-gamma , IP-10) or pro-tumor growth effects (VEGF, IL-8) were detected. CONCLUSION: IP IL-12 can safely be administered at this dose and schedule to patients after first line chemotherapy for ovarian/peritoneal carcinoma. The maximum response was stable disease. Future IP therapies with rhIL-12 will require better understanding and control of pleiotropic effects of IL-12.

Comparative analysis of peritoneum and tumor eicosanoids and pathways in advanced ovarian cancer.

PURPOSE: To describe the eicosanoid profile and differentially expressed eicosanoid and arachidonic acid pathway genes in tissues from patients with advanced epithelial ovarian cancer (EOC). EXPERIMENTAL DESIGN: We first employed electrospray tandem mass spectrometry to determine tissue-specific concentrations of the eicosanoids prostaglandin E2 (PGE2), the hydroxyeicosatetraenoic acids (12-HETE and 5-HETE), and leukotriene (LTB4), selected for tumor growth potential, and two other bioactive lipids (15-HETE and 13-HODE) with tumor cell proliferation interference potential. The cellular location of eicosanoid activity was identified by immunofluorescence antibody costaining and confocal microscopy. Differential analysis of eicosanoid and arachidonic pathway genes was done using a previously validated cDNA microarray platform. Tissues used included EOC tumor, tumor-free malignant peritoneum (MP), and benign peritoneum (BP) from patients with benign pelvic disease. RESULTS: (a) Eicosanoid products were detected in tumor, MP, and BP specimens. PGE2 levels were significantly elevated in tumors in an overall comparison with MP or BP (P < 0.001). Combined levels of PGE2, 12-HETE, 5-HETE, and LTB4 increased progressively from low to high concentrations in BP, MP, and tumors (P = 0.012). Neither 15-HETE nor 13-HODE showed a significant opposite trend toward levels found in BP. (b) Tissue specimens representing common EOC histotypes showed strong coexpressions of cyclooxygenases (COX-1) and prostaglandin E synthases (PGES-1) on tumor cells, whereas intratumoral or peritumoral MO/MA coexpressed COX-1 and COX-2 and PGES-1 and PGES-2, respectively. (c) cDNA microarray analysis of MP, BP, and tumor showed that a number of eicosanoid and arachidonic acid pathway genes were differentially expressed in MP and BP compared with tumor, except for CYP2J2, which was increased in tumors. CONCLUSIONS: Elevated levels of eicosanoid metabolites in tumors and differential expression of eicosanoid and arachidonic acid pathway genes in the peritoneum support the involvement of bioactive lipids in the inflammatory tumor environment of EOC.

Clinical trial endpoints in ovarian cancer: report of an FDA/ASCO/AACR Public Workshop.

OBJECTIVE: The unique characteristics of cancer, particularly issues involving the use of surrogate endpoints in clinical trials, present special challenges in the development of cancer drugs. In response, the U.S. Food and Drug Administration (FDA) has partnered with the American Society of Clinical Oncology, the American Association for Cancer Research, and the American Society of Hematology to conduct public workshops evaluating potential endpoints for drug approvals for the most common tumor types. METHODS: A workshop evaluating potential endpoints in ovarian cancer drug research was held in Bethesda, Maryland, in April 2006. Invited experts presented research findings and discussed endpoints in trials of drugs for treatment of Stage III and IV ovarian cancer. RESULTS: The panel responded to specific questions from FDA, discussing use of progression-free survival as a surrogate for overall survival and use of CA-125 levels as an indicator of response. Panel members also addressed endpoints in first-line therapy, second-line and subsequent therapy, and maintenance therapy. CONCLUSION: Expert commentary provided by panel members will inform FDA's draft guidance on clinical endpoints for cancer drug approvals and will be discussed at meetings of the FDA's Oncologic Drugs Advisory Committee. FDA intends to develop a set of principles that can be used to define efficacy standards for drugs used to treat ovarian and other cancers.

Hyaluronic acid-paclitaxel: antitumor efficacy against CD44(+) human ovarian carcinoma xenografts.

Numerous human tumor types, including ovarian cancer, display a significant expression of the CD44 family of cell surface proteoglycans. To develop tumor-targeted drugs, we have initially evaluated whether the CD44 ligand hyaluronic acid (HA) could serve as a backbone for paclitaxel (TXL) prodrugs. HA-TXL was prepared by modification of previous techniques. The in vitro cytotoxicity of HA-TXL against the CD44(+) human ovarian carcinoma cell lines SKOV-3ip and NMP-1 could be significantly blocked by preincubation with a molar excess of free HA. Female nude mice bearing intraperitoneal implants of NMP-1 cells were treated intraperitoneally with a single sub-maximum tolerated dose dose of HA-TXL or with multiple-dose regimens of paclitaxel (Taxol; Mead Johnson, Princeton, NJ) to determine the effects of these regimens on host survival and intraperitoneal tumor burden, with the latter being assessed by magnetic resonance imaging. NMP-1 xenografts were highly resistant to Taxol regimens, as host survival was only nominally improved compared to controls (T//C approximately 120), whereas single-dose HA-TXL treatment significantly improved survival in this model (T//C approximately 140; P = .004). In both NMP-1 and SKOV-3ip models, MR images of abdomens of HA-TXL-treated mice obtained shortly before controls required humane sacrifice revealed markedly reduced tumor burdens compared to control mice. This study is among the first to demonstrate that HA-based prodrugs administered locoregionally have antitumor activity in vivo.

Expression of CD40 and growth-inhibitory activity of CD40 ligand in ovarian cancer cell lines.

OBJECTIVE: Soluble recombinant human CD40 ligand trimer (rhuCD40Lt) has shown antitumor activity in preclinical and clinical studies. We evaluated the effect of rhuCD40Lt on epithelial ovarian carcinoma (EOC) cell lines. METHODS: Expression of the receptor, CD40, was determined by reverse transcriptase-polymerase chain reaction and flow cytometry, and antiproliferative effects of rhuCD40Lt, either alone or in combination with recombinant interferon-gamma (rIFN-gamma), were examined in 8 EOC lines. RESULTS: Expression of CD40 was elevated in 5 out of 8 EOC cell lines examined by flow cytometry, and the presence of CD40 transcripts was detected by RT-PCR in all 8 cell lines. CD40 expression was increased by rIFN-gamma, but treatment with rhuCD40Lt decreased CD40 expression in 4 of the 5 lines that had shown elevated CD40 expression. rhuCD40Lt had a growth-inhibitory effect on 2774 cells, which also exhibited the highest level of CD40 expression. Growth-inhibitory effect of rhuCD40Lt was additive with rIFN-gamma on 2774, NMP-1, a cisplatin-resistant subline of OVCAR3, and HEY cell lines. The number of apoptotic tumor cells was increased following treatment with rhuCD40Lt. CONCLUSIONS: CD40 is expressed on EOC cell lines, and expression was found at the transcript level in all of the EOC lines examined. rIFN-gamma enhances CD40 expression, though a decrease in CD40 expression was observed following treatment with rhuCD40Lt. Growth-inhibitory activity of rhuCD40Lt on EOC lines that express CD40 could be enhanced when rhuCD40Lt treatment was combined with rIFN-gamma. These results suggest that future studies of the combination of rhuCD40Lt and rIFN-gamma might warrant consideration.

Guidelines for data and safety monitoring for clinical trials not requiring traditional data monitoring committees.

This is a commissioned report by a writing committee formed by the Society for Clinical Trials. The committee was formed with the objectives of 1) reviewing data monitoring guidelines for confirmatory (phase III) trials published by the National Institutes of Health, US Food and Drug Administration, Veterans Administration, and the International Conference on Harmonisation and 2) proposing corresponding guidelines for exploratory clinical trials (ie, most phase I and phase II trials and others not requiring a fully independent data monitoring committee). These trials typically involve fewer subjects and are of shorter duration than phase III trials. Nevertheless there are safety concerns, especially because these are often the first human trials for a new intervention. Recommendations are given for appropriate elements of a data monitoring plan, decision criteria for institution of a data monitoring committee (DMC), and critical elements for a DMC to consider in exploratory trials. Review and approval of data monitoring plans are suggested to fall under Institutional Review Board purview. Forming a committee with all the characteristics of a traditional phase III trial monitoring committee may be warranted for a small fraction of exploratory trials. Such a panel could consist of both trial investigators and outside members. The paper concludes with examples of data and safety monitoring practice from the University of Wisconsin Comprehensive Cancer Center and the AIDS Clinical Trials Groups.