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The emergence of drug-resistant tumors during treatment remains one of the major obstacles in cancer chemotherapy. Overexpression of P-glycoprotein encoded by the multidrug resistance 1 (MDR1) gene or multidrug resistance-associated protein (MRP) (or both) and decreased expression of DNA topoisomerase II are responsible for expression of the multidrug resistance (MDR) phenotype. The expression of P-glycoprotein is also often observed in untreated cancers showing spontaneous MDR, such as renal cell carcinoma. Regarding cisplatin resistance, decreased cisplatin accumulation, an increase in cisplatin detoxification by glutathione-related enzymes or metallothionein (or both), and increased repair of DNA damage are all considered to play an important role. The combination of reversal agents targeting such drug resistance markers may be a way to improve the outcome of chemotherapy. Regarding the presently available reversal agents, however, clinically relevant chemosensitizing doses cannot be given to humans without inducing significant toxicity. The development of new agents that reverse drug resistance without causing significant toxicity and their clinical application based on the mechanisms regulating drug sensitivity may therefore be a potentially effective new treatment strategy for genitourinary carcinomas.

Partial nephrectomy using a microwave tissue coagulator can be safe and successful without renal pedicle clamping. However, the insertion line of the microwave electrode must be carefully determined for resection to be curative and safe, just as when making the cut line for conventional partial nephrectomy or tumor enucleation.

BACKGROUND We investigated whether a new marker of bone turnover, pyridinoline cross‐linked carboxyterminal telopeptide of type I collagen (ICTP), could be useful in the assessment of bone metastasis and in monitoring of the response to treatment in patients with prostate cancer with bone metastasis. METHODS In all, 58 patients with prostate cancer (25 with bone metastasis and 33 without bone metastasis) and 52 patients with benign prostate hypertrophy who were treated between June 1994–August 1997 were included in this study. All patients were newly diagnosed. RESULTS Serum ICTP levels in patients with prostate cancer with bone metastasis were significantly higher than those in patients with prostate cancer without bone metastasis (P < 0.0001) or with benign prostate hypertrophy (P < 0.0001). No significant differences were observed in serum ICTP levels between patients with prostate cancer without bone metastasis and those with benign prostate hypertrophy. Serum ICTP levels correlated significantly with Soloway's grading system for bone scans. Serum ICTP levels in patients with bone metastasis showed a significant downward trend in response to hormonal treatment. CONCLUSIONS The determination of serum ICTP levels is useful in the assessment of bone metastasis and in monitoring the response of bone metastasis to treatment to prostate cancer. Prostate 39:1–7, 1999. © 1999 Wiley‐Liss, Inc.