Correspondence

Case 5-1998: Bone Marrow Blasts in Chronic Myelomonocytic Leukemia

N Engl J Med 1998; 338:1925-1926June 25, 1998

Article

To the Editor:

There is an error in Table 3 of Case 5-1998 (Feb. 12 issue),1 which concerns a 51-year-old man with myelodysplasia and a pulmonary infiltrate. The percentage of blasts in the bone marrow of patients with chronic myelomonocytic leukemia should be 1 to 30 percent rather than 20 percent or more. Chronic myelomonocytic leukemia is similar in most respects to all the other subtypes of the French–American–British classification of myelodysplastic syndromes except for the presence of monocytosis (>1000 monocytes per microliter).2,3 The outcome of this disease is related to the percentage of blasts in bone marrow.

John M. Bennett, M.D.
University of Rochester Cancer Center, Rochester, NY 14642

3 References

1. 1

   Case Records of the Massachusetts General Hospital (Case 5-1998). N Engl J Med 1998;338:453-461
   Full Text | Web of Science | Medline

2. 2

   Kouides PA, Bennett JM. Morphology and classification of myelodysplastic syndromes. Hematol Oncol Clin North Am 1992;6:485-499
   Web of Science | Medline

3. 3

   Storniolo AM, Moloney WC, Rosenthal DS, Cox C, Bennett JM. Chronic myelomonocytic leukemia. Leukemia 1990;11:766-770
   

Author/Editor Response

Dr. Hayes replies:

To the Editor: Dr. Bennett is correct. The original French–American–British criteria for chronic myelomonocytic leukemia included a value for bone marrow blasts ranging from 1 to 20 percent,1 and this value is the most widely cited in several publications, including a 1992 review coauthored by Dr. Bennett.2 The range that he refers to in his letter has been cited in other articles and appears to be the currently accepted standard.3-5 As Dr. Bennett points out, this value is an important part of the diagnosis of chronic myelomonocytic leukemia, since a higher percentage of bone marrow blasts is associated with a poorer prognosis.4,5

Although this point is not relevant to the case discussion, I appreciate Dr. Bennett's vigilance.

Gerard B. Hayes, M.D., M.P.H.
Saint Elizabeth's Medical Center, Boston, MA 02135

5 References

1. 1

   Bennett JM, Catovsky D, Daniel MT, et al. Proposals for the classification of the myelodysplastic syndromes. Br J Haematol 1982;51:189-199
   Web of Science | Medline

2. 2

   Kouides PA, Bennett JM. Morphology and classification of myelodysplastic syndromes. Hematol Oncol Clin North Am 1992;6:485-499
   Web of Science | Medline

3. 3

   Fenaux P, Jouet JP, Zandecki M, et al. Chronic and subacute myelomonocytic leukaemia in the adult: a report of 60 cases with special reference to prognostic factors. Br J Haematol 1987;65:101-106
   CrossRef | Web of Science | Medline

4. 4

   Storniolo AM, Moloney WC, Rosenthal DS, Cox C, Bennett JM. Chronic myelomonocytic leukemia. Leukemia 1990;4:766-770
   Web of Science | Medline

5. 5

   Sanz GF, Sanz MA, Vallespi T, et al. Two regression models and a scoring system for predicting survival and planning treatment in myelodysplastic syndromes: a multivariate analysis of prognostic factors in 370 patients. Blood 1989;74:395-408
   Web of Science | Medline