Monocytosis is an adverse prognostic factor for survival in younger patients with primary myelofibrosis.

We recently developed a modified Dupriez prognostic scoring system (PSS) that effectively discriminated between high-, intermediate-, and low-risk young patients (age < or =60 years) with primary myelofibrosis (PMF) based on the respective presence of none, one, or two or more of the following parameters: hemoglobin <10 g/dL, leukocyte count <4 or >30 x 10(9)L(-1), and platelet count <100 x 10(9)L(-1). The current study (n=129; median age, 52 years; 69 males) reveals, on multivariable analysis, that an absolute monocyte count of > or =1 x 10(9)L(-1) carries an independent predictive value (p=0.02), for an inferior survival, in addition to that provided by hemoglobin level (p=0.002), platelet count (0.02), and leukocyte count (p=0.16). The inclusion of the monocyte count as a fourth risk factor enabled the construction of a new and improved Mayo PSS; median survival was 173, 61, and 26 months in the absence of all four (low-risk), three (intermediate-risk), or two or less (high-risk) adverse features, respectively (p<0.0001). The independent prognostic value of monocytosis was validated in a separate database of 97 patients with PMF from another institution.

Risk of non-hematologic cancer in individuals with high-count monoclonal B-cell lymphocytosis.

It is unknown whether individuals with monoclonal B-cell lymphocytosis (MBL) are at risk for adverse outcomes associated with chronic lymphocytic leukemia (CLL), such as the risk of non-hematologic cancer. We identified all locally residing individuals diagnosed with high-count MBL at Mayo Clinic between 1999 and 2009 and compared their rates of non-hematologic cancer with that of patients with CLL and two control cohorts: general medicine patients and patients who underwent clinical evaluation with flow cytometry but who had no hematologic malignancy. After excluding individuals with prior cancers, there were 107 high-count MBL cases, 132 CLL cases, 589 clinic controls and 482 flow cytometry controls. With 4.6 years median follow-up, 14 (13%) individuals with high-count MBL, 21 (4%) clinic controls (comparison MBL P<0.0001), 18 (4%) flow controls (comparison MBL P=0.0001) and 16 (12%) CLL patients (comparison MBL P=0.82) developed non-hematologic cancer. On multivariable Cox regression analysis, individuals with high-count MBL had higher risk of non-hematologic cancer compared with flow controls (hazard ratio (HR)=2.36; P=0.04) and borderline higher risk compared with clinic controls (HR=2.00; P=0.07). Patients with high-count MBL appear to be at increased risk for non-hematologic cancer, further reinforcing that high-count MBL has a distinct clinical phenotype despite low risk of progression to CLL.

Infectious complications among individuals with clinical monoclonal B-cell lymphocytosis (MBL): a cohort study of newly diagnosed cases compared to controls.

Although the risk of progression from monoclonal B-cell lymphocytosis (MBL) to chronic lymphocytic leukemia (CLL) has been well characterized, it is unknown whether other common complications associated with CLL, such as increased risk of infection, occurs in individuals with MBL. We used the Mayo CLL database to identify cohorts of individuals with newly diagnosed MBL (n=154) or newly diagnosed CLL (n=174) who resided within 50 miles of Mayo Clinic. A cohort of 689 adult patients seen for a general medical examination who resided within 50 miles of Mayo clinic and who enrolled in a case-control study of non-Hodgkin lymphoma (NHL) was used as a comparison cohort. Hospitalization with infection was more common among individuals with MBL (25/154; 16.2%), and CLL (32/174; 18.4%) than controls (18/689; 2.6%). On pooled multivariable Cox proportional hazards analysis of all 1017 patients (controls, MBL and CLL), male sex (hazards ratio (HR)=2.3; P=0.002), major co-morbid health problems (HR=1.7, P=0.04), the presence of CLL (HR=3.2, P<0.001), treatment for progressive CLL (HR=2.4, P=0.001) and the presence of MBL (HR=3.0, P=0.001) were independently associated with risk of hospitalization for infection. These results suggest the risk of serious infection in clinical MBL is substantially greater than the risk of progression requiring treatment.