Early tandem high-dose ifosfamide, carboplatin, etoposide therapy with stem cell rescue for small-cell lung cancer: brief report on the results of a phase-I/II trial

Standard versus Dose-Intensified Chemotherapy with Sequential Reinfusion of Hematopoietic Progenitor Cells in Small Cell Lung Cancer Patients with Favorable Prognosis

PURPOSE

The combination of ifosfamide, carboplatin, and etoposide (ICE) is highly effective in treating small cell lung cancer (SCLC). Myelosuppression resulting in leukopenia and thrombocytopenia is the dose-limiting toxicity.

PATIENTS AND METHODS

This phase 3 study assessed 2-year survival improvement with dose intensification of ICE chemotherapy (ICT) in patients with good-prognosis SCLC. Patients received up to six cycles of ICT with filgrastim-supported sequential reinfusion of peripheral blood progenitor cells every 14 days, or standard ICE (SCT) every 28 days.

RESULTS

Eighty-three patients were randomized to ICT (n = 42) or SCT (n = 41). Median survival was significantly improved with ICT (30.3 mo) versus SCT (18.5 mo; p = 0.001); 2-year survival was 55% for ICT and 39% for SCT (p = 0.151). Time to progression (TTP) was significantly improved, with 15 months for ICT versus 11.1 months for SCT (p = 0.0001). Overall response rates were 100 and 88% for ICT and SCT, respectively (p = 0.0258). SCT was associated with significantly less grade 3 and 4 leukopenia at day 8 (p < 0.0001), less thrombocytopenia at day 14 (p < 0.0001), and more favorable platelet nadir (p < 0.0001). The need for platelet and red blood cell transfusions significantly increased in the ICT group (p < 0.0001). Nonhematologic adverse events in both groups were comparable and mostly grade 1 or 2.

CONCLUSION

Patients receiving ICT with filgrastim achieved significant increases in median survival and TTP despite an increased need for transfusions.

Combined Chemoradiotherapy in Small Cell Lung Cancer

Combined chemoradiotherapy is the established standard of care for limited stage small cell lung cancer; it provides cure in 15% to 25% of patients. Early concurrent therapy imparts a 5% long-term survival benefit compared with sequential therapy. Hyperfractionated delivery of radiotherapy may provide a small incremental benefit when compared with standard fractionation. Radiotherapy dose escalation and reduced radiotherapy volumes are feasible; however, survival benefit has not been confirmed. Cisplatin and etoposide remain the preferred chemotherapy agents. New chemotherapeutic agents and novel treatment approaches are under intense investigation.

Use of calcimimetics in uremic patients with secondary hyperparathyroidism: review

Recognition of the role of the extracellular calcium sensing receptor (CaR) in mineral metabolism has greatly improved our understanding of calcium homeostasis. The activation of this receptor by small changes in extracellular ionized calcium (ec(Ca2+)) regulates PTH, calcitonin secretion, urinary calcium excretion, and ultimately, bone turnover. The cloning of this CaR and the discovery of mutations making the receptor less or more sensitive to calcium allowed a better understanding of several hereditary disorders characterized either by hyperparathyroidism or hypoparathyroidism. This CaR became an ideal target for the development of compounds, the calcimimetics, able to amplify the sensitivity of the CaR to ec(Ca2+) suppressing PTH levels with a resultant fall in blood Ca2+. The first clinical studies with first-generation calcimimetic agents have demonstrated their efficacy lowering plasma intact PTH concentration in uremic patients with secondary hyperparathyroidism. However, the low bioavailability of these first calcimimetics predicts a difficult clinical utilization. The second-generation calcimimetic AMG-073, with a better pharmacokinetic profile, appears to be effective and safe for the treatment of secondary hyperparathyroidism, producing suppression of PTH levels with a simultaneous reduction in serum phosphorus levels and the calcium X phosphorus product. The advantage of controlling PTH secretion without the complications related to hypercalcemia, hyperphosphatemia, and increased calcium X phosphorus product is very promising.