International Staging System predicts prognosis of Chinese patients with multiple myeloma across different calendar periods with application of novel agents

The applicability of the International Staging System (ISS) for Chinese patients with multiple myeloma (MM) has not been demonstrated, especially with respect to treatments with novel agents. Newly diagnosed MM patients at Taipei Veterans General Hospital were enrolled between 1996 and 2007. Data regarding clinical features, laboratory tests, and outcome at last follow-up were collected. A total of 389 MM patients (71% male) were enrolled, with median age of 71 years. At diagnosis, 72.7% had Durie–Salmon (DS) stage III disease, 56.2% had ISS stage III disease, and 34% had serum creatinine ≧2.0 mg/dL. Compared with patients diagnosed in the first calendar period 1996–2001, the patients of the second calendar period 2002–2007 were older and more of these patients had received novel agents, especially thalidomide. The median overall survival period was 20.5 months, with a significant increase of patients in the second calendar period (15.3 and 28.2 months, respectively; P = 0.002), especially for those with ISS stages I and II. In the Cox proportion model, elevated serum β₂ microglobulin at diagnosis (≧3.5 mg/L), old age (≧65 years), and impaired renal function were found to be independently associated with poor survival. Over the entire period, the ISS was found to be effective in providing an accurate prognosis with respect to different ages and calendar periods. This is the first study to show the applicability of ISS for Chinese patients with MM, especially for those who had received thalidomide.