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D Kelsen

Publications and source records attributed to D Kelsen.

At least 19 recordsLinked to original sources
PubMed2001

Phase II study of the cyclin-dependent kinase inhibitor flavopiridol administered to patients with advanced gastric carcinoma.

PURPOSE: Flavopiridol is the first cyclin-dependent kinase inhibitor to enter clinical trials. Activity in gastric cancer xenografts and in a patient with gastric cancer on the phase I trial led to this phase II study of flavopiridol in patients with metastatic gastric cancer. PATIENTS AND METHODS: Sixteen patients were entered onto the study, and 14 were assessable for response. Flavopiridol was administered initially at a dose of 50 mg/m(2)/d by continuous infusion for 72 hours every 2 weeks. Assessment of plasma pharmacokinetics was performed in all patients. Peripheral mononuclear cells were collected throughout the 72-hour infusion for determinants of apoptosis. RESULTS: There were no major objective responses (exact confidence interval 0% to 23%). One patient achieved a minor response in his liver metastases, though the primary progressed. Other patients exhibited histologic and radiographic evidence of tumor necrosis. Common toxicities included fatigue in 93% of patients (grade 3 or 4 in 27%) and diarrhea in 73% of patients (grade 3 or 4 in 20%). Five patients (33%) developed venous thromboses at the central catheter tip. The studies performed on peripheral mononuclear cells indicated no induction of apoptosis. CONCLUSION: Flavopiridol administered as a single agent for 72 hours every 14 days is inactive in the treatment of gastric cancer. The drug also induced an unexpected higher incidence of vascular thrombosis and fatigue than was anticipated from the phase I trials. Future development of flavopiridol will depend on other doses and schedules in combination with chemotherapy.

Adenocarcinoma↗
PubMed2001

Phase I study of topoisomerase I inhibitor exatecan mesylate (DX-8951f) given as weekly 24-hour infusions three of every four weeks.

Exatecan mesylate (DX-8951f) is a topoisomerase I inhibitor that has increased solubility and antitumor activity compared with other topoisomerase I inhibitors. The purpose of this study was to establish a safe dose of DX-8951f given as a weekly 24-h infusion 3 of every 4 weeks. DX-8951f was administered as a 24-h continuous infusion in escalating doses. Twenty-seven patients were treated with 81 courses of the drug. Dose-limiting toxicities included neutropenia, thrombocytopenia, and inability to administer all three doses in the first cycle. In minimally pretreated patients, a dose of 0.8 mg/m(2) was tolerable. In patients who were heavily pretreated, a slightly lower dose, 0.53 mg/m(2), was tolerated without any severe toxicities. Nonhematological toxicities were mild and consisted of mild diarrhea, asthenia, mild nausea, and constipation. Pharmacokinetic parameters could be well described with a one-compartment model in most patients, although the application of the one-compartment model probably resulted in an underestimated elimination half-life. In conclusion, the recommended Phase II dose for DX-8951f administered as a weekly 24-h infusion on a 3-of-4 week schedule is 0.8 mg/m(2) in minimally pretreated patients and 0.53 mg/m(2) in patients who are heavily pretreated.

Aged↗
PubMed1998

Phase I clinical and pharmacologic study of weekly cisplatin combined with weekly irinotecan in patients with advanced solid tumors.

PURPOSE: In vitro synergy between cisplatin and irinotecan (CPT-11) has been reported. We designed a combination schedule of these agents to maximize the potential for synergistic interaction. PATIENTS AND METHODS: To maximize the opportunity for synergy, we divided the cisplatin into four consecutive weekly treatments, followed by a 2-week rest. Each dose of cisplatin was immediately followed by a dose of irinotecan. The dose of cisplatin was fixed at 30 mg/m2/wk. The initial irinotecan dose was 50 mg/m2/wk and this was escalated by 30% increments in successive cohorts of three to six patients to establish the maximum-tolerated dose (MTD). Pharmacokinetics of irinotecan and its metabolites, SN-38 and SN-38 glucuronide (SN-38G), were analyzed. RESULTS: Of 35 patients with solid tumors enrolled onto this trial, 30 were assessable for toxicity and response. The MTD for this regimen was 30 mg/m2/wk of cisplatin plus 50 mg/m2/wk of irinotecan in previously treated patients and 30 mg/m2/wk of cisplatin plus 65 mg/m2/wk of irinotecan in chemotherapy-naive patients. Neutropenia was the dose-limiting toxicity (DLT) encountered in this trial. Diarrhea was infrequent and rarely dose-limiting. Seven of 30 assessable patients achieved a partial response. No alteration in irinotecan, SN-38, or SN-38G pharmacokinetics resulted from the administration of cisplatin with irinotecan. CONCLUSION: The administration of cisplatin and irinotecan on this weekly schedule provides a practical and well-tolerated regimen that has the potential to maximize any clinical synergy between the two agents. Evidence of substantial clinical activity was seen in this phase I study.

Adult↗
PubMed1998

UCN-01 suppresses thymidylate synthase gene expression and enhances 5-fluorouracil-induced apoptosis in a sequence-dependent manner.

UCN-01, a protein kinase C/cyclin-dependent kinase inhibitor, suppressed thymidylate synthase (TS) protein expression in a dose-dependent manner with near complete suppression at 1 microM after a 24-h exposure in human gastric cancer cell line SK-GT5. Other protein kinase C/cyclin-dependent kinase inhibitors, including flavopiridol and safingol, had a similar effect on TS protein expression, but to a lesser degree. Moreover, UCN-01 repressed the induction of TS after 5-fluorouracil (FU) exposure by 90-95% and significantly enhanced the induction of apoptosis by FU from 4-8% with either FU or UCN-01 alone to 46+/-1% (P < 0.005 versus either single drug, reverse sequence, or the combination) when UCN-01 was given after FU. The effect of UCN-01 on TS was associated with a dose-dependent suppression of the E2F-1 protein, a transcriptional activator of TS. Northern blot analysis revealed that TS mRNA levels decreased gradually as the concentration of UCN-01 increased, but that E2F-1 mRNA levels remained relatively unchanged. UCN-01 may provide a novel way to enhance cellular sensitivity toward FU by means of suppressing TS expression mediated mainly by down-regulation of E2F-1.

Alkaloids↗
PubMed1997

High frequency of simultaneous loss of p16 and p16beta gene expression in squamous cell carcinoma of the esophagus but not in adenocarcinoma of the esophagus or stomach.

Quantitative reverse transcription PCR (RT-PCR) was used to measure gene expressions (relative mRNA levels) of p16 and the alternate transcript pl6beta in esophageal and gastric tumors. p16 gene expression was undetectable in 13 of 25 esophageal squamous cell carcinomas. In 11 of these tumors, pl6beta was simultaneously missing whereas two of the pl6-deficient tumors still expressed p16beta. Among 34 esophageal adenocarcinomas and 11 gastric adenocarcinomas, only one tumor lacked p16 expression and all tumors expressed p16beta. p16 sequences were not detectable by PCR in genomic DNA from tumors lacking both p16 and p16beta mRNA, suggesting that the simultaneous loss of both gene expressions resulted from homozygous genomic deletion of the p16 gene. However, DNA from tumors that lacked p16 mRNA but expressed pl6beta did contain the p16 gene, consistent with loss of p16 expression in these tumors by transcriptional suppression. No point mutations in p16 cDNA were detected among 12 that were sequenced, but one p16 cDNA from a squamous cell carcinoma had a 19-base deletion, possibly indicating a splice-site mutation. Among those tumors that expressed p16 mRNA, the gene expression values of both p16 and pl6beta varied over a wide range. In some cases, p16 expression was detectable but low, suggesting that down-regulation of p16 expression may be used in some cases to achieve the funtional equivalent of gene deletion or transcriptional silencing. These results demonstrate that p16 expression patterns differ based on tumor histology and origin. Homozygous deletion of p16 appears to be common in esophageal squamous cell carcinomas but in adenocarcinomas, both gene deletion and transcriptional silencing of p16 were infrequent.

Adenocarcinoma↗
PubMed1997

Multimodality therapy for adenocarcinoma of the esophagus.

The incidence of adenocarcinoma of the esophagus is rapidly increasing in the Western world. In North America and western Europe, a marked shift in the epidemiologic profile of this disease has occurred. In the past, most patients with esophageal cancer were found to have epidermoid carcinoma. These patients frequently abused tobacco or alcohol, had multiple comorbid medical conditions, and were elderly. Over the last 10 to 15 years, a rapid increase in the number of patients having adenocarcinoma of the esophagus has been noted. In contrast, these patients are predominantly young white men from 35 to 55 years old who much less frequently smoke or drink, and many have few or no comorbid medical conditions, are fit, and are able to tolerate aggressive combined therapy. This article focuses on the adenocarcinoma subgroup of patients, although identical therapeutic approaches are being studied in appropriate patients with epidermoid carcinomas.

Adenocarcinoma↗
PubMed1997

A phase II trial of paclitaxel and cisplatin in patients with locally advanced metastatic esophageal cancer: a preliminary report.

We demonstrated in an earlier trial that paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) has substantial antineoplastic activity, with acceptable toxicity, in patients with advanced metastatic esophageal cancer. Preclinical and clinical data from studies in other tumors indicate substantial additive or even synergistic activity for paclitaxel/cisplatin combination chemotherapy. We encountered substantial toxicity with a cisplatin/paclitaxel/5-fluorouracil combination. To maximize paclitaxel dose, we initiated a phase II trial using cisplatin and paclitaxel alone. This report summarizes preliminary data from that trial. Paclitaxel 200 mg/m2 is given as a continuous, 24-hour infusion on day 1. On day 2, cisplatin 75 mg/m2 is given. Courses are repeated every 21 days. Dose adjustments are based on myelosuppression, neurotoxicity, and (for cisplatin) renal or auditory toxicity. All patients receive recombinant human granulocyte colony-stimulating factor to minimize the risk of neutropenic fever. The primary end point of the study is tumor regression. Secondary end points include duration of response and toxicity. Two groups of patients are being studied. Those with advanced metastatic disease receive chemotherapy alone as palliative treatment. The second group has locoregional disease that is potentially resectable. These patients receive combined-modality therapy involving induction paclitaxel/cisplatin chemotherapy followed by surgery. To date, 37 evaluable patients have been treated. Twenty had advanced metastatic disease and 17 were treated before planned surgery. Twenty-seven patients had adenocarcinoma and 10 had epidermoid carcinoma. Major objective responses were seen in 49% of all patients, with similar response rates for patients with metastatic and locoregional disease. The median duration of response for patients with metastases is 4+ months. Among 14 patients treated before surgery, one experienced a complete pathologic response, and the neoplasms of 43% were downstaged. Primary toxicity was neutropenia, which was tolerable. Surgical morbidity or mortality did not increase. Cisplatin plus paclitaxel is an active combination in the treatment of patients with advanced or locoregional esophageal cancer. Further studies with this combination both in metastatic and locally advanced disease are indicated.

Adult↗
PubMed1996

A phase I trial of a modified, dose intensive FAMTX regimen (high dose 5-fluorouracil+doxorubicin+high dose methotrexate+leucovorin) with oral uridine rescue.

BACKGROUND: Dose intensification of 5-fluorouracil (5-FU) is complicated by increased toxicity. 5-FU is a fluorine-substituted pyrimidine analog of uracil. In preclinical studies, administration of oral uridine (Ur) has been shown to allow for dose intensification of 5-FU with enhancement of its antitumor activity. Therefore, a Phase I trial was designed aimed at dose intensification of 5-FU as a component of a modified 5-FU-doxorubicin-methotrexate (FAMTX) regimen using oral Ur rescue. METHODS: Methotrexate (MTX) was administered to all patients at a fixed dose of 1.5 g/m2. MTX was followed 24 hours later by escalating doses of 5-FU starting at 800 mg/m2 with leucovorin rescue. Cycles of 5-FU and MTX were repeated every 15 days. Every other cycle, patients received doxorubicin. "Adria cycles") at a dose of 30 mg/m2. Oral Ur was administered at a dose of 8 gm/m2 every 6 hours for 12 doses. In the first phase of the study, patients received Ur only if they developed Grade 3 or 4 hematologic toxicity. In the second phase, all patients received Ur 24 hours after 5-FU on all cycles. RESULTS: Without Ur rescue, the maximum tolerated dose (MTD) of 5-FU was 900 mg/m2 on the Adria cycles and 1.1 gm/m2 on the non-Adria cycles. With Ur, the MTD of 5-FU increased to 1.2 gm/m2 on the Adria cycles and to 1.6 gm/m2 on the non-Adria cycles. CONCLUSIONS: In this modified FAMTX regimen, oral Ur administration allowed for dose-intensification of 5-FU, with a 33% increase in the MTD of 5-FU on the Adria cycles and a 45% increase in the MTD of 5-FU dose on the non-Adria cycles.

Administration, Oral↗
PubMed1996

Neoadjuvant therapy for upper gastrointestinal tract cancers.

Esophageal, gastric, and pancreatic cancers frequently present with extensive local regional disease, which can be difficult to resect or to definitively control with radiation therapy given as a single modality. In addition, these patients are at high risk for the development of distant metastasis. Neoadjuvant chemotherapy is a promising experimental approach for the use of combined modality treatments that involve a systemic component. The theoretical background for the use of chemotherapy followed by an operation or chemotherapy plus radiation in these tumors has been extensively described. For esophageal cancer, many phase II trials have demonstrated tolerance to systemic chemotherapy; chemotherapy plus radiation prior to operation has more toxicity. Definitive phase III studies testing the hypothesis that this approach is superior to operation alone have recently been performed in the United States and Europe. These data are currently being analyzed. For the use of combined modality therapy of chemoradiation, random assignment trials have demonstrated an improvement in cure rate for patients with squamous cell carcinomas of the esophagus. Preliminary data suggest a similar outcome for adenocarcinoma, but the number of patients who have been studied is smaller. Newer phase III studies involve the use of new systemic agents that have demonstrated activity in metastatic disease (such as paclitaxel) or the use of higher doses of radiation therapy. For gastric cancer, a substantial number of phase II trials have again demonstrated tolerance to preoperative chemotherapy with no increase in operative morbidity or mortality. Small-scale phase III trials have been performed that suggest an improvement in outcome. Definitive studies are in the planning stage. Finally, for pancreatic carcinoma, in which local control is an even more difficult issue, a major stumbling block remains the development of newer systemic therapies that have activity in this disease. The recent identification of gemcitabine as having modest activity as a single agent and its potential use with radiation therapy is being explored in the neoadjuvant setting.

Antineoplastic Agents↗
PubMed1996

Neoadjuvant therapy of high-risk gastric cancer: a phase II trial of preoperative FAMTX and postoperative intraperitoneal fluorouracil-cisplatin plus intravenous fluorouracil.

PURPOSE AND METHODS: We identified patients with gastric cancer at high risk for recurrence before therapy using endoscopic ultrasonography (EUS). Neoadjuvant therapy using the fluorouracil, doxorubicin, and metrotrexate (FAMTX) regimen was given for three courses before planned laparotomy with the intention to perform curative resection. Postoperatively, intraperitoneal (IP) cisplatin and fluorouracil (FU) and intravenous (i.v.) FU were administered to patients undergoing resection. RESULTS: Fifty-six assessable patients were treated. Preoperative FAMTX therapy was tolerable, with the major toxicity being neutropenic fever. One treatment-related death was seen. Eighty-nine percent of patients underwent surgical exploration and 61% had potentially curative resections. There were two postoperative deaths. Comparison of pathologic tumor (pT) stage with EUS-predicted tumor stage showed apparent downstaging in 51% of patients. Postoperative IP chemotherapy was delivered to 75% of eligible patients. Toxicity was acceptable. There was no increase in operative morbidity or mortality compared with concurrent nonstudy patients undergoing a similar operative procedure and not receiving preoperative therapy. With a median follow-up time of 29 months, the median survival duration was 15.3 months. For patients who underwent potentially curative resections, the median survival duration was 31 months. Peritoneal failure was seen in 16% of patients. CONCLUSION: Chemotherapy with the FAMTX regimen is tolerable in patients with locally advanced gastric cancer, without an increase in operative morbidity or mortality. IP therapy can be successfully delivered to most resected patients. The intraabdominal failure pattern appears to be decreased compared with expected. This approach is an appropriate investigational arm to pursue in future studies.

Adenocarcinoma↗
PubMed1995

Phase I radioimmunotherapy trial with iodine-131-CC49 in metastatic colon carcinoma.

UNLABELLED: CC49 is a murine monoclonal antibody (MAb) that reacts against the TAG-72 antigen. We carried out a Phase I study with escalating doses of 131I-CC49 in patients with advanced colorectal cancer expressing the TAG-72 antigen to determine the dose-limiting toxicity and therapeutic efficacy, if any, of the radioimmunoconjugate. METHODS: Twenty-four patients with TAG-72- expressing colorectal cancer were treated with escalating doses of 131I-CC49 starting at 15 mCi/m2 and going up to 90 mCi/m2 of 131I labeled to 20 mg MAb CC49. Patients were selected if TAG-72 was expressed in > or = 50% of cells in previously resected tumor and at least one metastasis was demonstratable on standard imaging such as CT. All patients had failed conventional chemotherapy and had not received prior radiotherapy or murine MAb. Patients were under radiation isolation precautions until whole-body radioactivity decreased to < or = 5 mR/hr at 1 m. Whole-body scintigrams were obtained prior to discharge and 1 and 2 wk after infusion in all patients. SPECT imaging was carried out at least once in all patients. RESULTS: All patients had excellent targeting of radioactivity to known tumor sites. There was no nonhematologic toxicity. Hematologic toxicity was more pronounced in those patients who had received extensive prior chemotherapy. There were no major responses. All patients developed an immune response (HAMA) within 4 wk of therapy. CONCLUSION: Radioimmunotherapy with 131I-CC49 is safe and there is significant therapeutic efficacy in this Phase I trial at the doses studied. There is excellent targeting of radioactivity to antigen-positive tumors. Dose-limiting toxicity is hematopoietic, with the maximum tolerated dose in this group of heavily pretreated patients being 75 mCi/m2.

Abdominal Neoplasms↗
PubMed1994

A phase I trial of intrahepatic verapamil and doxorubicin. Regional therapy to overcome multidrug resistance.

BACKGROUND: Verapamil can modulate multidrug resistance in vitro, but only at levels that are not tolerable when administered systemically. Regional strategies of drug administration may permit the delivery of high concentrations of a drug to specific areas with lower systemic levels. Colorectal cancers typically express the multidrug resistance phenotype. METHODS: A Phase I trial was performed to determine the maximum tolerable dose (MTD) and dose limiting toxicities of verapamil by hepatic artery infusion, together with doxorubicin, to patients with hepatic metastases of colorectal cancer. Fourteen patients with metastatic colorectal cancer received a 14-hour intrahepatic infusion of verapamil. Six hours after the start of the infusion, a fixed dose of doxorubicin (50 mg/m2) was given, also via the hepatic artery, over a 30-minute period. Patients were followed by cardiac telemetry but were not in an intensive care setting, and no invasive monitoring was used. All patients had received prior intrahepatic chemotherapy. RESULTS: The MTD of intrahepatic verapamil on this schedule in this patient population was 1.2 mg/kg/hour. Hypotension was the dose limiting toxicity. No major objective responses were noted in this heavily pretreated patient population. A dose of 1.0 mg/kg/hour is recommended for Phase II trials. CONCLUSIONS: Based on estimations of normal hepatic artery blood flow, the estimated concentration of verapamil delivered to the hepatic tumors at 1.0 mg/kg/hour is 3.6 micrograms/ml (7.3 microM), which is comparable to concentrations at which an in vitro reversal of MDR is seen. This study demonstrates that the systemic toxicities of an MDR reversal agent can be overcome by regional drug delivery, establishing this approach as an important model system for further study of MDR modulation.

Adenocarcinoma↗
PubMed1994

A phase II trial of alpha-interferon and 5-fluorouracil in patients with advanced carcinoid and islet cell tumors.

BACKGROUND: 5-Fluorouracil (5-FU) has shown modest single-agent activity in patients with carcinoid or islet cell tumors. Alpha interferon (alpha-IFN) has also shown modest single agent activity in these diseases, although biologic responses have been far more prevalent than have objective tumor regressions. The combination of alpha-IFN and 5-FU has demonstrated enhanced activity in several gastrointestinal malignancies. METHODS: Twenty-one patients with advanced neuro-endocrine tumors (14 with carcinoid tumors, 7 with islet cell carcinomas) were treated with alpha-IFN and 5-FU in a Phase II study. 5-Fluorouracil was administered by intravenous bolus injection at an initial dose of 400 mg/m2/day for 5 consecutive days. After a 1-week break, 5-FU then was administered weekly by intravenous bolus at a dose of 750 mg/m2. Alpha interferon administration was begun on Day 1 of 5-FU at a daily dose of 3 x 10(6) U subcutaneously and continued for the duration of the trial. RESULTS: Of the 14 carcinoid patients with carcinoid tumors, 1 experienced a partial response (7%; 95% confidence interval [CI] 0-20%) that lasted for 6 months. Eight of the patients with carcinoid tumors achieved stable disease for a median of 6 months (range, 2-10 months). One of the patients with islet cell tumors (14%; 95% CI 0-39%) achieved a partial response that persisted after 8 months; 4 patients with islet cell tumors had stable disease for a median of 13 months (range, 4-27+ months). Even at this relatively low dose of alpha-IFN, 14 of 21 patients required a dose reduction in the alpha-IFN (13 for fatigue, 1 for ataxia). Three patients experienced myelosuppression of greater than Grade 3, and three patients had diarrhea of greater than Grade 3. One patient experienced dose-limiting hand-foot syndrome. CONCLUSIONS: These results suggest that the combination of 5-FU and alpha-IFN does not have any clear superiority over the individual agents alone; 5-FU appears to reduce patient tolerance of alpha-IFN when given on a daily schedule. Further investigations are needed to identify active agents in the treatment of neuroendocrine malignancies.

Adenoma, Islet Cell↗
PubMed1994

Preoperative 5-fluorouracil, low-dose leucovorin, and concurrent radiation therapy for rectal cancer.

BACKGROUND: A Phase I trial was performed to determine the maximum tolerated dose of concurrent preoperative radiation therapy (5040 cGy) and 2 cycles (bolus daily times 5) of 5-fluorouracil (5-FU) and low-dose leucovorin (LV) (20 mg/m2), followed by surgery and 10 cycles of postoperative 5-FU/LV in patients with primary or recurrent rectal cancer. METHODS: Twenty-four patients were entered into the study. Preoperatively, the initial dose of 5-FU was 325 mg/m2. 5-FU was escalated 50 mg/m2, while the dose of LV and radiation therapy remained constant. Chemotherapy and radiation began concurrently on day 1. The postoperative chemotherapy was not dose escalated; 5-FU, 425 mg/m2, and LV, 20 mg/m2. The median follow-up was 10 months (range, 4-19 months). RESULTS: The resectability rate with negative margins in the 23 patients who underwent surgery was 100%. One patient refused surgery. The pathologic complete response rate was 13% (3 of 23). An additional four patients had negative nodes and a microscopic foci of tumor in the bowel wall. Therefore, the total clinical complete response rate was 30% (7 of 23). The maximum tolerated dose of 5-FU for the preoperative combined modality segment was 375 mg/m2; therefore, the recommended Phase II dose level is 325 mg/m2. The incidence of Grade 3+ toxicity for the 22 patients treated at the recommended 5-FU dose level (325 mg/m2) during the preoperative combined modality segment was as follows: diarrhea, 14%; erythema, 5%; hematologic, 10%; and total, 18%. The median nadir counts were leukocyte count, 3.7 (range, 1.5-5.9); hemoglobin count, 12.2 (range, 10.2-14.3); and platelet count (times 1000), 165 (range, 92-237). CONCLUSIONS: With this regimen, the recommended doses of chemotherapy in the combined modality segment are slightly higher than those recommended in arm 2 of the Intergroup postoperative adjuvant rectal trial 0114. This regimen will serve both as the preoperative arm of the Intergroup randomized trial of preoperative versus postoperative combined modality therapy for resectable rectal cancer (INT R9401) as well as the basis for the combined modality segment of NSABP RO-3.

Adenocarcinoma↗