New Staging System Viable for Myeloma Treated With Novel Therapies

Researchers from Japan believe they have identified a novel staging system based on hemoglobin and plasmacytoma that may help to stratify patients with multiple myeloma who are treated with novel therapeutics, according to their results published recently in European Journal of Haematology.

“Our study suggested that a new staging system consisting of anemia and plasmacytoma, both of which are simply determined in the routine clinical examination, is more useful than international staging system in the era of novel agents,” wrote Hirono Iriuchishima, MD, of the department of medicine and clinical science at Gunma University, Japan, and colleagues.

The international staging system (ISS) is a widely accepted prognostic staging system for patients with multiple myeloma. However, according to the study, this system was “suboptimal” in Asian patients, and was established prior to 2002 with data that did not take into account novel therapeutics.

Therefore, in this analysis, Iriuchishima and colleagues sought to examine if the ISS staging system had value in patients treated with novel therapeutics and to discover possible new prognostic factors that could help to stratify patients.

The researchers analyzed data from 178 patients with newly diagnosed multiple myeloma between 1993 and 2012. Patients had received either conventional chemotherapy (n = 79) or chemotherapy with novel therapeutics (n = 99). The majority of conventional chemotherapy regimens were melphalan/prednisone, vincristine/doxorubicin/dexamethasone, or high-dose dexamethasone. Novel therapeutics included thalidomide, bortezomib, and lenalidomide.

Looking at only those patients treated with conventional chemotherapy, overall survival was significantly different depending on the distinct stages of ISS (stage I, 8.09 years; stage II, 3.79 years; stage III, 1.32 years). In contrast, no significant difference in overall survival by ISS stage was seen for patients treated with chemotherapy and a novel agent (stage I, 5.44 years; stage II, 8.13 years; stage III, 5.68 years).

Next the researchers performed an analysis to identify possible prognostic factors that existed in patients treated with novel therapeutics. Only anemia, with a hemoglobin of less than 10 g/dL, and plasmacytoma were significantly associated with a reduced overall survival among these patients. ISS stage was not identified as an independent prognostic factor.

Using an alternative staging system, the researchers classified patients as stage I (hemoglobin 10 g/dL or greater and absence of plasmacytoma), stage II (anyone who is not stage I or stage III), and stage III (hemoglobin 10 g/dL or less and presence of plasmacytoma). Patients treated with novel therapeutics had significantly different overall survival when stratified using this new system (stage I, 8.13 years; stage II, 5.95 years, and stage III, 2.45 years).

“The questions of why ISS has lost its impact on overall survival in multiple myeloma patients treated with the novel agents remains unanswered,” the researchers wrote. “Further prospective studies are necessary to confirm our results and to help guide rational risk-adapted therapy.”