{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,9]],"date-time":"2026-05-09T13:35:13Z","timestamp":1778333713012,"version":"3.51.4"},"reference-count":0,"publisher":"S. Karger AG","license":[{"start":{"date-parts":[[2009,2,17]],"date-time":"2009-02-17T00:00:00Z","timestamp":1234828800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/karger.com\/pages\/terms-and-conditions"},{"start":{"date-parts":[[2009,2,17]],"date-time":"2009-02-17T00:00:00Z","timestamp":1234828800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/karger.com\/pages\/terms-and-conditions"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Acta Haematol"],"abstract":"<jats:p>Patients with monoclonal gammopathy of undetermined significance (MGUS) have a serum monoclonal component (M-component), but no evidence of multiple myeloma, macroglobulinaemia, amyloidosis or other plasma cell proliferative disease. A long-term follow-up study (median 11.5 years) has been carried out in 263 cases of MGUS, 159 males (60.5%) and 104 females (39.5%), aged 40-89 years (median 66.5 years). The actuarial probability for malignant transformation was 6.1, 15.4 and 31.3% at 5, 10 and 20 years, respectively. At the final evaluation, 157 patients (59.7%), 119 (45.3%) of whom with no increase and 38 (14.4%) with an increase in serum M-component, died of causes unrelated to MGUS and without development of any plasma cell proliferative disease; 47 patients (17.9%) were still alive without increase in M-component; 11 patients (4.1 %) were still alive and at follow-up presented values of serum M-component &gt; 30 g\/l without any evidence of plasma cell proliferative or lymphoproliferative disease; 48 patients (18.3%) developed multiple myeloma (35 cases, 13.1%), solitary plasmacytoma of the bone (2 cases, 0.8%), macroglobulinaemia (4 cases, 1.6%), malignant lymphoma (3 cases, 1.2%), amyloidosis (2 cases, 0.8%), chronic lymphocytic leukaemia (1 case, 0.4%), and plasma cell leukaemia (1 case, 0.4%). The patients developing multiple myeloma, solitary plasmacytoma, macroglobulinaemia and plasma cell leukaemia had an increase in serum M-component, whereas no increase was found in malignant lymphoma, amyloidosis and chronic lymphocytic leukaemia. These findings and the data in the literature suggest that MGUS could be considered a preneoplastic condition; since no clinical and laboratory features are able to identify in advance the patients at high risk of disease progression, each patient must be followed up indefinitely.<\/jats:p>","DOI":"10.1159\/000203676","type":"journal-article","created":{"date-parts":[[2009,2,18]],"date-time":"2009-02-18T15:14:43Z","timestamp":1234970083000},"page":"174-179","source":"Crossref","is-referenced-by-count":47,"title":["The Natural History of Monoclonal Gammopathy of Undetermined Significance"],"prefix":"10.1159","author":[{"given":"Paolo","family":"Pasqualetti","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vittorio","family":"Festuccia","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Antonio","family":"Collacciani","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Raffaele","family":"Casale","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"127","published-online":{"date-parts":[[2009,2,17]]},"container-title":["Acta Haematologica"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.karger.com\/Article\/Pdf\/203676","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/karger.com\/article-pdf\/doi\/10.1159\/000203676","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T11:36:06Z","timestamp":1777462566000},"score":1,"resource":{"primary":{"URL":"https:\/\/karger.com\/article\/doi\/10.1159\/000203676"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2009,2,17]]},"references-count":0,"URL":"https:\/\/doi.org\/10.1159\/000203676","archive":["Portico"],"relation":{},"ISSN":["0001-5792","1421-9662"],"issn-type":[{"value":"0001-5792","type":"print"},{"value":"1421-9662","type":"electronic"}],"subject":[],"published":{"date-parts":[[2009,2,17]]}}}