Tetrathiomolybdate-associated copper depletion decreases circulating endothelial progenitor cells in women with breast cancer at high risk of relapse.

BACKGROUND: Bone marrow-derived endothelial progenitor cells (EPCs) are critical for metastatic progression. This study explores the effect of tetrathiomolybdate (TM), an anti-angiogenic copper chelator, on EPCs in patients at high risk for breast cancer recurrence. PATIENTS AND METHODS: This phase 2 study enrolled breast cancer patients with stage 3 and stage 4 without evidence of disease (NED), and stage 2 if triple-negative. TM 100 mg orally was administered to maintain ceruloplasmin <17 mg/dl for 2 years or until relapse. The primary end point was change in EPCs. RESULTS: Forty patients (28 stage 2/3, 12 stage 4 NED) were enrolled. Seventy-five percent patients achieved the copper depletion target by 1 month. Ninety-one percent of triple-negative patients copper-depleted compared with 41% luminal subtypes. In copper-depleted patients only, there was a significant reduction in EPCs/ml by 27 (P = 0.04). Six patients relapsed while on study, of which only one patient had EPCs maintained below baseline. The 10-month relapse-free survival was 85.0% (95% CI 74.6%-96.8%). Only grade 3/4 toxicity was hematologic: neutropenia (3.1% of cycles), febrile neutropenia (0.2%), and anemia (0.2%). CONCLUSIONS: TM is safe and appears to maintain EPCs below baseline in copper-depleted patients. TM may promote tumor dormancy and ultimately prevent relapse.

Positron emission tomography for the evaluation of patients with colorectal cancer.

Approximately 40% of patients treated with curative intent for colorectal carcinoma eventually recur. In about one third of these patients, the lesion is localized and potentially resectable. Typically, the recurrence is characterized by findings on diagnostic imaging studies and may be accompanied by a rise in the serum carcinoembryonic antigen (CEA) levels. In a few patients, however, the asymptomatic rise in CEA is not accompanied by diagnostic findings on computed tomography (CT). We report a case herein, of a patient with rising CEA, noted 1 year after completion of adjuvant chemotherapy for node-positive colorectal cancer. CT and laparoscopic exploration were nondiagnostic. In order to further evaluate the rise in CEA, positron emission tomography (PET) was performed. PET revealed an area of increased uptake in the right lobe of the liver. Resection of the metastatic liver lesion resulted in a subsequent drop in the CEA levels.

A phase I/II trial of 5-fluorouracil and etoposide in metastatic colorectal carcinoma.

Twenty-two patients with metastatic colorectal carcinoma were treated in a Phase I-II study of combination therapy with 5-fluorouracil (5-FU) and etoposide (VP-16). Treatment consisted of weekly intravenous VP-16, 100-120 mg/M2, followed by 5-FU, 400-480 mg/M2, in 28-day cycles. Myelosuppression was the dose-limiting toxicity with a mean nadir leukocyte count of 3,600/mm3 and a mean nadir thrombocyte count of 101,000/mm3. There were no episodes of sepsis or bleeding. The tolerable dose for this regimen is VP-16, 110 mg/M2, and 5-FU, 440 mg/M2, weekly. A total of 63 cycles of chemotherapy were given. Although 10 patients had stabilization of disease, no partial or complete responses were documented. We conclude that there is no clinical support for the in vitro synergy observed with this combination. Further trials of this combination using this schedule in colorectal carcinoma are not indicated.