Long-term exposure to circulating platinum is associated with late effects of treatment in testicular cancer survivors.

BACKGROUND: The success of cisplatin-based (Platinol, Bristol-Myers Squibb Company, New York, NY, USA) chemotherapy for testicular cancer comes at the price of long-term and late effects related to healthy tissue damage. We assessed and modelled serum platinum (Pt) decay after chemotherapy and determined relationships between long-term circulating Pt levels and known late effects. PATIENTS AND METHODS: In 99 testicular cancer survivors, treated with cisplatin-based chemotherapy, serum and 24-h urine samples were collected during follow-up (1-13 years after treatment). To build a population pharmacokinetic model, measured Pt data were simultaneously analysed, together with cisplatin dose, age, weight and height using the NONMEM software. Based on this model, area under the curve between 1 and 3 years after treatment (Pt AUC1-3 years) was calculated for each patient. Predicted long-term Pt exposure was related to renal function and to late effects of treatment assessed median 9 (3-15) years after chemotherapy. RESULTS: Decay of Pt was best described by a two-compartment model. Mean terminal T1/2 was 3.7 (range 2.5-5.2) years. Pt AUC1-3 years correlated with cumulative cisplatin dose, and creatinine clearance before and 1 year after treatment. Patients with paraesthesia had higher Pt AUC1-3 years (30.9 versus 27.0 µg/l month) compared with those without paraesthesia (P = 0.021). Patients with hypogonadism, elevated LDL-cholesterol levels or hypertension also had higher Pt AUC1-3 years. CONCLUSIONS: Renal function before and after cisplatin treatment is an important determinant of long-term Pt exposure. Known long-term effects of testicular cancer treatment, such as paraesthesia, hypogonadism, hypercholesterolaemia and hypertension, are associated with long-term circulating Pt exposure.

Shared-care survivorship program for testicular cancer patients: safe and feasible.

BACKGROUND: Testicular cancer survivors are at risk for cardiovascular disease, often preceded by early development of cardiovascular risk factors due to chemotherapeutic treatment. Therefore, close collaboration between oncologists and primary care physicians (PCPs) is needed during follow-up to monitor and manage cardiovascular risk factors. We designed a shared-care survivorship program, in which testicular cancer patients visit both their oncologist and their PCP. The objective of this study was to test the safety and feasibility of shared-care follow-up after treatment for metastatic testicular cancer. PATIENTS AND METHODS: The study was designed as an observational cohort study with a stopping rule to check for the safety of follow-up. Safety boundaries were defined for failures in the detection of signals indicating cancer recurrence. Secondary outcomes were the proportion of carried out cardiovascular risk assessments, psychosocial status and patient preferences measured with an evaluation questionnaire. RESULTS: One hundred and sixty-two patients were enrolled (69% of eligible testicular cancer patients). Almost all (99%, n = 150) PCPs of the enrolled patients agreed to participate in the study. In total, 364 primary care visits took place. No failures occurred in the detection of relapsed testicular cancer. Four follow-up visits were considered as failures because of organizational issues, without activation of the stopping rule. Eventually, the safe boundary was crossed indicating that this shared-care model is a safe alternative for follow-up after testicular cancer. Patients were satisfied with the knowledge level of PCPs. PCPs were willing to further extend their role in follow-up care after cancer. CONCLUSIONS: Shared-care follow-up is safe and feasible in this patient population. Patients benefit from personalized care, partly close to their home. Within shared care, PCPs can have an important role in cardiovascular risk management and psychosocial survivorship issues.