M A Dimopoulos1, E Kastritis2, E Michalis3, C Tsatalas4, M Michael5, A Pouli6, Z Kartasis7, S Delimpasi8, D Gika2, A Zomas9, M Roussou2, K Konstantopoulos10, A Parcharidou11, K Zervas12, E Terpos2. 1. Department of Clinical Therapeutics, University of Athens School of Medicine, Athens. Electronic address: mdimop@med.uoa.gr. 2. Department of Clinical Therapeutics, University of Athens School of Medicine, Athens. 3. Department of Hematology, 'G. Gennimatas' Hospital, Athens. 4. Department of Haematology, Democritus University of Thrace Medical School, Alexandroupolis, Greece. 5. Department of Haematology, Nicosia General Hospital, Nicosia, Cyprus. 6. Department of Hematology, 'Saint Savvas' Anticancer Hospital, Athens. 7. Department of Hematology, Chalkis General Hospital, Chalkis. 8. Department of Hematology, 'Evangelismos' Hospital, Athens. 9. Fourth Department of Internal Medicine, 'Attikon' University Hospital, Athens. 10. First Department of Medicine, University of Athens School of Medicine, Athens. 11. Third Department of Internal Medicine, Red Cross Hospital 'Korgialenio Benakio', Athens. 12. Department of Hematology, 'Theagenion' Cancer Center, Thessaloniki, Greece.
Abstract
BACKGROUND: The International Staging System (ISS) is the most widely used staging system for patients with multiple myeloma (MM). However, serum β2-microglobulin increases in renal impairment (RI) and there have been concerns that ISS-3 stage may include 'up-staged' MM patients in whom elevated β2-microglobulin reflects the degree of renal dysfunction rather than tumor load. PATIENTS AND METHODS: In order to assess the impact of RI on the prognostic value of ISS, we analyzed 1516 patients with symptomatic MM and the degree of RI was classified according to the Kidney Disease Outcomes Quality Initiative-Chronic Kidney Disease (CKD) criteria. RESULTS: Forty-eight percent patients had stages 3-5 CKD while 29% of patients had ISS-1, 38% had ISS-2 and 33% ISS-3. The frequency and severity of RI were more common in ISS-3 patients. RI was associated with inferior survival in univariate but not in multivariate analysis. When analyzed separately, ISS-1 and ISS-2 patients with RI had inferior survival in univariate but not in multivariate analysis. In ISS-3 MM patients, RI had no prognostic impact either in univariate or multivariate analysis. Results were similar, when we analyzed only patients with Bence-Jones >200 mg/day. CONCLUSIONS: ISS remains unaffected by the degree of RI, even in patients with ISS-3, which includes most patients with renal dysfunction.
BACKGROUND: The International Staging System (ISS) is the most widely used staging system for patients with multiple myeloma (MM). However, serum β2-microglobulin increases in renal impairment (RI) and there have been concerns that ISS-3 stage may include 'up-staged' MM patients in whom elevated β2-microglobulin reflects the degree of renal dysfunction rather than tumor load. PATIENTS AND METHODS: In order to assess the impact of RI on the prognostic value of ISS, we analyzed 1516 patients with symptomatic MM and the degree of RI was classified according to the Kidney Disease Outcomes Quality Initiative-Chronic Kidney Disease (CKD) criteria. RESULTS: Forty-eight percent patients had stages 3-5 CKD while 29% of patients had ISS-1, 38% had ISS-2 and 33% ISS-3. The frequency and severity of RI were more common in ISS-3 patients. RI was associated with inferior survival in univariate but not in multivariate analysis. When analyzed separately, ISS-1 and ISS-2patients with RI had inferior survival in univariate but not in multivariate analysis. In ISS-3 MM patients, RI had no prognostic impact either in univariate or multivariate analysis. Results were similar, when we analyzed only patients with Bence-Jones >200 mg/day. CONCLUSIONS: ISS remains unaffected by the degree of RI, even in patients with ISS-3, which includes most patients with renal dysfunction.