- Email: [email protected]
Prognostic implication and characterization of the blast cell population in the myelodysplastic syndrome
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PROGNOSTIC IMPLICATION AND C I I A R A C T E R I Z A T I O N OF THE BLAST CELL POPULATION IN THE MYELODYSPLASTIC SYNDROME* Jti,,\N-[A,TIIz~NNE G()AS(;UIIN.- JOHN M. BtNNIT'I .:i: CItRISI()PHt-~R C()x,~ HEX!RY ltAu[~t,t-.'~',]] G[It.I...XM MtF'1[]] and GtiOR(it s FI.,.XNI)RIN¢ +Universite de Rcnnes, ll6pital Sud. Rennes, France: :~Universit3 ~)f Rochestcr, Cancer ('enter, Medical Ontology Unit. Rochester, New York. U.S.A.: §Universit3 of Rochester Medical ('enter. I)ivision of Biostatistics. Rochester, New York, U.S.A. ; IlKing's ('ollcgc School of Medicine, l.ondon. t!.K. and qll6pital Necker, Paris. t.rance (Re('eMed 24 April 1991 ,.lcc~Tted 1 June 1991 )
Abstract -The bone marrow smears of 18 contirmed cases of kiDS were analyzed carefully fl)r the presence of "'hypcrgranular type Ill hlasts", defined as more than 20 tine azurophil primary granules per cells. The concordance was close to 80",f among 5 obse|vers. Thirty-nine percent (7 cases) were reclassified as RAI.-B-t rather than RAEB. The presence of these hypergranular blasts was not suggestive of increased differentiation but rather leukemic cells. The reassignment of cases altered the median survival for the various subcategories, providing a clearer separation with the introduction of type Ill blasts than without utilizing these cells which were ,,eparated from the pmmyeloeyte family.. ]-he introduction of this new blast cell dclinition in a larger series ot patients is recommended to confirm these preliminary observations. Key words: Myelodysplastic syndrome, I~last cells, prognostic factor
with 21-3{r~4 blasts. A study by Sanz et al. [3] has demonstrated a survival difference between patients having 5-10c:/- blasts from those with 11-2004 blasts. It becomes important, therefore, to more precisely separate promyelocytes, which are viewed as differentiating or more maturing cells, from blasts that have more than a moderate number of granules. In view of this we propose a definition of blast type I and blast type II, and introduce another blast cell termed "'blast type llI", and we have initiated a study based on these new morphologic characteristics in patients with MDS to demonstrate the difference between the promyelocytic population, both normal and so-called abnormal promyelocytes [4, 5] and the agranular (type 1). granular (type ll) and hypergranular (type lll) blast cell populations. In this paper we have examined the prevalence of type Ill blasts in 18 patients with MDS and have detailed the concordance of observers as well as the impact of counting these cells a m o n g type I and type II blasts on survival and leukemic progression.
INTRODU('TION THe-: "French-American-British" (FAB) group's classification of the myelodysplastic syndrome (MDS) provides a definition of blast cells [1, 2]. Type I blasts are defined by the absence of azurophil granules or A u e r rods and type 11 blasts have identical features but contain "'a few primary (azurophil) granules". The FAB group did not define the upper limits of how many granules could be present. Potentially, this could result in ambiguity in distinguishing myeloblasts from promyelocytes and might explain the variability in the percentage of MDS subclasses reported in the literature. The percentage of blasts may be the single most important prognostic factor both in terms of overall survival as well as leukemic transformation. The FAB classification recognizes ~hree groups of patients according to the percentage of blasts: cases with less than 5 ~ blasts, cases with 5-20c~ blasts and patients Supported by grants from Association pour la recherche sur le Cancer: ARC. France, Fondation Langlois, France, grants CA-11083 and CAd 1198 from the National Cancer Institute, NIII. U.S.A. Correspondence to: Dr J. E. Goasguen, Laboratoire d'Hematologic, H6pital Sud. 16 Boulevard de Bulgarie, 35056 Rennes Cedex, France.
MATERIALS AND METItODS Patient,s
Eighteen patients, 10 males and 8 females (sex ratio M/F: 1 25) with a median age of 71 vr (45-g0) with MDS 1159
J.-E. GOASGU[:N et al.
1160
TABLE 1. CRITERIA FOR TIlE t,VAI.UA'FION r)F BI.AST ('EI.I.S IN M D S
Cell features
Type I
Type II
Type Ill
Promyelocytes
Position nucleus Chromatin Nucleolus Golgi zone Granules Basophilic cytoplasm
Central Fine 1-2
Central Fine 1--2 -,:~211 +++
Central Fine 1--2 --:-20 +++
Peripheral Coarse 1 (large) Present Numerous +
I) +++
previously classified as refractory anemia (RA) or refractory anemia with excess of blasts (RAEB) in one institution (JG) were investigated for a new evaluation of blast cells. Bone marrow smears from these patients were circulated among the investigators who performed a myelogram on all cases using the cytologic definitions described in Table 1. It is important to note that these patients were selected because the senior author had observed at least occasional type llI blasts as defined below in contrast to other series. No selection was made with regard to outcome, however. Morphologic characterization: The cells were defined as follows and summarized in Table 1 Blasts. A type I blast is a typical agranular blast cell without azurophilic granules in the cytoplasm (Fig. 3); a type II blast is a cell with less than twenty primary cytoplasmic azurophilic granules, basophilic cytoplasm, absence of golgi zone, uncondensed chromatin with one or more nucleoli (Fig. 2); a type III blast is defined as above but with more than twenty azurophilic granules in the cytoplasm (Figs 1 and 3). Promyelocytes. Typical promyelocytes were defined as large cells that contain a prominent golgi zone, eccentric nucleus, prominent nucleoli and numerous azurophilic granules. When the azurophilic granules were clumped in some area of the cytoplasm and had heterogeneous size. promyelocytes were classified as abnormal. Myelocytes. When the cytoplasm was not basophilic, the cell was called a classical myelocyte, even if some azurophilic granules are still present. It is sometimes difficult to make a distinction between an abnormal promyelocyte, a late promyelocyte and a myelocyte. Therefore, for the present study all promyelocytes and mature granulocytes were called "maturing cells". Classification. Based on a study published by Sanz et al. [3] which demonstrated a survival difference within RAEB subclassification by separating two groups, the former containing less than 10% blasts (5-10%), and the latter containing 11-20% blasts, we also have incorporated this limit into our study. Patients were classified as including or not type III blasts and separated into RA (blast type I + II <5%), RAEB I (blast type I + II or I + II + Ill > 5 % but <10%), RAEB II (blast type I + II or I + II + I I I >10% but <20%), and RAEB-t (blast type I + II or I + II + I I I >20% but <30%). Method All of the slides were counted using these criteria by five of the authors. Five hundred cells were counted in each case on continuous fields, excluding lymphocytes, plasma cells and monocytes. Results were compared by statistical
analysis and survival curves established by the KaplanMeier method. Survival curves were compared using a standard non-parametric test [6]. The reproducibility of this cytological characterization was also tested among the observers. RESULTS The eighteen cases were firstly classified as R A or R A E B according to the n u m b e r of type I and type II blasts calculated as the mean of the counts of all the observers (called original diagnosis in Table 3). The introduction of type 111 blasts and separation between R A E B 1 and R A E B 11 provides new results (Table 2) and a different distribution of subclasses (Table 3). Reproducibility of the classification in R A , R A E B I, R A E B II, R A E B - t was tested with and without inclusion of type III blasts. The c o n c o r d a n c e was defined as total a g r e e m e n t on the subclassification between original diagnosis and those p r o p o s e d by each observer. T h e c o n c o r d a n c e a m o n g the five observers was 70% at the original diagnosis and 77% at the revised diagnosis (with type III blasts). Based on the original F A B criteria for type I and I I blasts, 7 patients were classified as R A E B I and 10 as R A E B II. Utilizing the type III blast the following alterations occurred: 4 cases r e m a i n e d as R A E B I (one shifting from R A ) ; 4 patients a d v a n c e d to R A E B II; 7 patients m o v e d from R A E B II to R A E B - t . Survival data Survival data were calculated in two different ways. Based on the traditional F A B classification (Table 3), referred to as 'original diagnosis' we c o m p a r e d (Fig. 4) groups I - I V (11 patients) with g r o u p V (7 patients). The estimated median survival time for group V is 7 m o n t h s (standard deviation = 3.9 months) c o m p a r e d to 15 m o n t h s (standard deviation = 2.2 m o n t h s ) , p value = 0.06, using the Mantel-Cox test. The data were reanalyzed based on the introduction of type III blasts into the classification (Table 3, revised diagnosis). T h e revised curves are displayed in Fig. 5. T h e r e are now 3 separate curves
Fill. 1. Hypergranular blast cell (type III) with more than 20 azurophil granules in the cytoplasm.
,, ~.
.~:
FIG. 2. Typical myeloblast (type If) with only some granules.
q
f
FIG. 3. Hypergranular (type III) and agranular (type I) blasts associated with other dysplastic mature cells from a RAEB-t. 1161
1163
The blast cell population TABLE 2. PERCENTAGE OF CELLS COUNTED BY 5 OF TIlE CO-AUTHORS (500 CELLS COUNT) ON CONSECUTIVE FIELDS IN ALL 18 CASES OF M D S . TtlE CASES IIAVE BEEN REARRANGED IN ORDER OF PROGRESSIVE INCREASE IN BLAST CEt.L PERCENTAGE Blast subtype No.
Age
1
II
III
MA
1 2 3 4 5 6 7 16 8 9 15 10 11 12 13 14 17 18
61 50 66 80 56 76 80 45 78 75 59 75 56 51 76 70 74 72
2 I 4 1 5 2 6 3 8 10 10 14 6 6 7 8 14 10
2 5 2 5 3 6 4 7 7 2 3 3 10 6 7 9 5 3
3 4 3 3 6 3 2 7 4 5 5 3 8 11 6 11 7 16
Median =
71
6
5
5.5
F,R*
Survival
Outcome
LT
73 59 55 78 73 64 57 77 70 67 40 39 66 59 66 38 57 30
20 31 36 13 13 25 31 6 11 16 42 41 10 18 14 34 17 41
37 60 15 11 30 24 14 12 6 16 2 7 12 15 4 2 18 2
D A D D D A D D D D D I) D D D D D D
AML2 --AML2 AML2 ---AML2 AML2 AML2 AML2 AML2 AML2 AML2 AML2 ..AML2 AML2
61.5
22
13
M A , m a t u r e granulocytes; E R . erythroid precursors; I,T, leukemic t r a n s f o r m a t i o n : D, d e a d : A, alive.
TABLE 3. |NCIDENCE OF TYPE 111 BI.ASI S AND MODIFICATIONS OF "1It1( ORIGINAl,. CLASSIFI('AIION BY M D S SUBTYPES: R A E B I = BLASTS :>5c'/c AND "< l()c/c; R A E B II = BLASTS > l i C k AND <:20c7c; R A E B - t = BLASTS >20r~ AND < 3 0 ~ Diagnosis Survival m e d i a n No.
Blast I + II
1
4
2 3 4
Subtypes I + II + Ill
Original
Revised
Group
7
RA
I
37
37
I
6 6 6
10 9 9
i I i
I I I
60 15 11
28
!I
5 6 7 16
8 8 ll) 10
14 11 12 17
I I I I
I II II II
30 24 14 12
8 9 15
15 11 13
19 13 18
II II lI
II II II
6 16 2
10 11 12 13 14 17 18
17 16 12 14 17 19 13
20 24 23 20 28 26 29
II II II II II II II
RAEB-t RAEB-t RAEB-t RAEB-t RAEB-t RAEB-t RAEB-t
7 12 15 4 "~ 18 2
III
II
IV
V
1164
J.-E. (.;oAst;t 1.0
:~
0.8
I)IS('USSION 0.6
:i
0
~
04
~
02
I '
I
I
--
I
Group 1-4
J
I
I Group 5 I
O0
,b
2o
3'o 4'o Months
50
60
t:l(;. 4. Kaplan-Meier survival curves for RA + RAEB vs RAEB-t.
( R A E B I, R A E B II, RAEB-t). The median survivals are 15 months (SD: 13 m), 14 months (SD: 3 m) and 7 months (SD: 4 m) respectively. The p value for using the Mantel-Cox test is 0.10. The resorting or reclassification with the type III blast cells improves the median survival of R A E B l from 24 to 31 months and R A E B It from 8.4 to 15.0 months.
1.0
i
~08
t
i i
0
I
o
I .....................
el. ~
et al.
A n examination of the percentage of promyelocytes and other maturing granulocytes for correlation with survival revealed no consistent pattern.
c,")
~ 06
t.~
0.4
"5 E
I I
(.O 0 . 2
I I_
i, .......................
Group 1
Group 2
I
I I
I
00 ' 10
RAEB-! ' 20
30
4'0
' 50
6'0
Months
FK;. 5. Kaplan-Meier survival curves for group 1 (RAEB I), group 2 (RAEB II and RAEB-t) aftcr inclusion of hypcrgranular blast (type III).
Since 1982 several studies on prognosis features and scoring systems have demonstrated the clinical importance of blast cell identitication and its implication on survival duration in MDS [3. 7, l(J]. The aim of the present study was to evaluate a new blast characterization in order to appreciate the dysgranulopoiesis which affects the primary azurophilic granules and its impact on survival. Dysgranulopoiesis is a well-known feature of MDS. Persistance of basophilia and the early development of azurophil granules makes the distinction between myeloblast (type II) and promyelocyte difficult [3.4, 7-9]. In this study we have defined a leukemic cell on the basis of features identical to myeloblasts previously described but with more granules. By applying the criteria of type 1. 11 and III blasts to a series of 18 cases of MDS we have identitied approximately 17c~ of cases whose outcome is worse than other cases of R A E B I with the diagnosis changing to R A E B 11 by the introduction of type III blasts. Moreover. some cases, previously diagnosed as RAEB II are reclassitied as RAEB-(. The shift from the "'progranulocyte'" category is equivalent to a median of 5.5 additional blasts/'cases. The highest percentage of type I11 blasts (11'7,~, 11(;, 16<)~ respectively) occurred in R A E B II. in view of the high risk of leukemic transformation particularly and strikingly FAB M2 in these cases, the granular blasts are not suggestive of increasing differentiation, but rather granule-positive blasts, i.e. leukemic cells. This serves to emphasize thai! some patients with RAEB will have a bad outconle, particularly when the blast percentage exceeds 10%. For those patients who tire reclassified as RAEB-t, and are under the 50yr, the introduction of combination chemotherapy, possibly with recombinant GM-('SF or GCSF might achieve a higher percentage of remissions with resulting improved survival. The survival curve of Mf)S patients has already been related to the number of type 1 blasts [3]. We recently demonstrated [1()] thal type I and lypc II blasts are a major criteria for subclasses and prognosis supports the importance identilication and the potential value of including type 111 blasts. The failure to demonstrate significance at a p value of 0 . 0 5 or less may relate to the relatively small number of cases. ('ertainlv the trend suggests that there m a y ,*'ell be a difference if larger numbers of cases were reviewed.
The blast cell population REFERENCES 1. Bennett J. M.. Catovsky D., Daniel M. T.. Flandrin G., Galton D. A. G., Gralnick tl. R. & Sultan C. (1982) Proposals for the classification of the mvelodysplastic syndromes. Br. J. ttaemat. 51, 189. 2. Bennett J. M.. Catovsky D.. Daniel M. T.. Flandrin G., Galton I). A. G., Gralnick H. R. & Sultan ('. (1985) Proposed revised criteria for the classific~,tion of the acute myeloid leukemia: a report of the FrenchAmerican-British group. Ann. Int. Med. 106, 626. 3. Sanz G. F., Sanz M. A., Vallespi T., Canizo (7.. Torrabedella M., Garcia S., lrriguible D. & San Miguel J. (1989) Two regression models and a scoring system for predicting survival and phmning treatment in mveIodysplastic syndromes. A multivariate analysis of prognostic factors in 370 patients. Blood 74, 3(.)5. 4. Breton-Gorit, s J., ltoussav D. & Dreyfus B. (1975) Partial myeloperoxidase d'eliciency in a case of preleukemia. I. Studies of line structure and peroxidase synthesis of promyelocytes. Br. J. ttaemat. 30, 273. 5. Scoazec J. Y., Imbert M.. Crofts M.. Jouaull t1..
6. 7.
8.
9.
10.
1165
Juneja S. K., Vernant J. P. & Sultan C. (1985) Myelodysplastic syndrome or acute myeloid leukemia'? A study of 28 cases presenting with borderline features. ('ancer 55, 2390. Cox D. R. & Oakes D. (1984) Analysis ~{ Surt,it,al Data. Chapman and Flail, London, U . K Greenberg P. L. (1983) The smoldering myeloid leukemic states: clinical and biologic features. Blood 61, 1035. Groupe Francais de Morphologie Hematologique (1987) French registry of acute leukemia and mveIodysplastic syndromes. Cancer 60, 1385. Dreyfus B.. Sultan C.. Rochant H., Salmon C., Mannoni P.. ('artron J. P., Boivin P. & Galand C. (1969) Anomalies of blood group antigens and cr.vthrocytes enzymes in two types of chronic relractorv anaemia. Br. J. ttaemat. 16, 303. (ioasgucn J. E., Garand R., Bizet M., Bremond J. I,.. Gardais J., Callat M. P.. Accard F. & Caperon J. (1990) Prognostic factors of myelodysplastic syndromes. A simplified 3D scoring system. I,eukemia Re~. 3, 255.
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PROGNOSTIC IMPLICATION AND C I I A R A C T E R I Z A T I O N OF THE BLAST CELL POPULATION IN THE MYELODYSPLASTIC SYNDROME* Jti,,\N-[A,TIIz~NNE G()AS(;UIIN.- JOHN M. BtNNIT'I .:i: CItRISI()PHt-~R C()x,~ HEX!RY ltAu[~t,t-.'~',]] G[It.I...XM MtF'1[]] and GtiOR(it s FI.,.XNI)RIN¢ +Universite de Rcnnes, ll6pital Sud. Rennes, France: :~Universit3 ~)f Rochestcr, Cancer ('enter, Medical Ontology Unit. Rochester, New York. U.S.A.: §Universit3 of Rochester Medical ('enter. I)ivision of Biostatistics. Rochester, New York, U.S.A. ; IlKing's ('ollcgc School of Medicine, l.ondon. t!.K. and qll6pital Necker, Paris. t.rance (Re('eMed 24 April 1991 ,.lcc~Tted 1 June 1991 )
Abstract -The bone marrow smears of 18 contirmed cases of kiDS were analyzed carefully fl)r the presence of "'hypcrgranular type Ill hlasts", defined as more than 20 tine azurophil primary granules per cells. The concordance was close to 80",f among 5 obse|vers. Thirty-nine percent (7 cases) were reclassified as RAI.-B-t rather than RAEB. The presence of these hypergranular blasts was not suggestive of increased differentiation but rather leukemic cells. The reassignment of cases altered the median survival for the various subcategories, providing a clearer separation with the introduction of type Ill blasts than without utilizing these cells which were ,,eparated from the pmmyeloeyte family.. ]-he introduction of this new blast cell dclinition in a larger series ot patients is recommended to confirm these preliminary observations. Key words: Myelodysplastic syndrome, I~last cells, prognostic factor
with 21-3{r~4 blasts. A study by Sanz et al. [3] has demonstrated a survival difference between patients having 5-10c:/- blasts from those with 11-2004 blasts. It becomes important, therefore, to more precisely separate promyelocytes, which are viewed as differentiating or more maturing cells, from blasts that have more than a moderate number of granules. In view of this we propose a definition of blast type I and blast type II, and introduce another blast cell termed "'blast type llI", and we have initiated a study based on these new morphologic characteristics in patients with MDS to demonstrate the difference between the promyelocytic population, both normal and so-called abnormal promyelocytes [4, 5] and the agranular (type 1). granular (type ll) and hypergranular (type lll) blast cell populations. In this paper we have examined the prevalence of type Ill blasts in 18 patients with MDS and have detailed the concordance of observers as well as the impact of counting these cells a m o n g type I and type II blasts on survival and leukemic progression.
INTRODU('TION THe-: "French-American-British" (FAB) group's classification of the myelodysplastic syndrome (MDS) provides a definition of blast cells [1, 2]. Type I blasts are defined by the absence of azurophil granules or A u e r rods and type 11 blasts have identical features but contain "'a few primary (azurophil) granules". The FAB group did not define the upper limits of how many granules could be present. Potentially, this could result in ambiguity in distinguishing myeloblasts from promyelocytes and might explain the variability in the percentage of MDS subclasses reported in the literature. The percentage of blasts may be the single most important prognostic factor both in terms of overall survival as well as leukemic transformation. The FAB classification recognizes ~hree groups of patients according to the percentage of blasts: cases with less than 5 ~ blasts, cases with 5-20c~ blasts and patients Supported by grants from Association pour la recherche sur le Cancer: ARC. France, Fondation Langlois, France, grants CA-11083 and CAd 1198 from the National Cancer Institute, NIII. U.S.A. Correspondence to: Dr J. E. Goasguen, Laboratoire d'Hematologic, H6pital Sud. 16 Boulevard de Bulgarie, 35056 Rennes Cedex, France.
MATERIALS AND METItODS Patient,s
Eighteen patients, 10 males and 8 females (sex ratio M/F: 1 25) with a median age of 71 vr (45-g0) with MDS 1159
J.-E. GOASGU[:N et al.
1160
TABLE 1. CRITERIA FOR TIlE t,VAI.UA'FION r)F BI.AST ('EI.I.S IN M D S
Cell features
Type I
Type II
Type Ill
Promyelocytes
Position nucleus Chromatin Nucleolus Golgi zone Granules Basophilic cytoplasm
Central Fine 1-2
Central Fine 1--2 -,:~211 +++
Central Fine 1--2 --:-20 +++
Peripheral Coarse 1 (large) Present Numerous +
I) +++
previously classified as refractory anemia (RA) or refractory anemia with excess of blasts (RAEB) in one institution (JG) were investigated for a new evaluation of blast cells. Bone marrow smears from these patients were circulated among the investigators who performed a myelogram on all cases using the cytologic definitions described in Table 1. It is important to note that these patients were selected because the senior author had observed at least occasional type llI blasts as defined below in contrast to other series. No selection was made with regard to outcome, however. Morphologic characterization: The cells were defined as follows and summarized in Table 1 Blasts. A type I blast is a typical agranular blast cell without azurophilic granules in the cytoplasm (Fig. 3); a type II blast is a cell with less than twenty primary cytoplasmic azurophilic granules, basophilic cytoplasm, absence of golgi zone, uncondensed chromatin with one or more nucleoli (Fig. 2); a type III blast is defined as above but with more than twenty azurophilic granules in the cytoplasm (Figs 1 and 3). Promyelocytes. Typical promyelocytes were defined as large cells that contain a prominent golgi zone, eccentric nucleus, prominent nucleoli and numerous azurophilic granules. When the azurophilic granules were clumped in some area of the cytoplasm and had heterogeneous size. promyelocytes were classified as abnormal. Myelocytes. When the cytoplasm was not basophilic, the cell was called a classical myelocyte, even if some azurophilic granules are still present. It is sometimes difficult to make a distinction between an abnormal promyelocyte, a late promyelocyte and a myelocyte. Therefore, for the present study all promyelocytes and mature granulocytes were called "maturing cells". Classification. Based on a study published by Sanz et al. [3] which demonstrated a survival difference within RAEB subclassification by separating two groups, the former containing less than 10% blasts (5-10%), and the latter containing 11-20% blasts, we also have incorporated this limit into our study. Patients were classified as including or not type III blasts and separated into RA (blast type I + II <5%), RAEB I (blast type I + II or I + II + Ill > 5 % but <10%), RAEB II (blast type I + II or I + II + I I I >10% but <20%), and RAEB-t (blast type I + II or I + II + I I I >20% but <30%). Method All of the slides were counted using these criteria by five of the authors. Five hundred cells were counted in each case on continuous fields, excluding lymphocytes, plasma cells and monocytes. Results were compared by statistical
analysis and survival curves established by the KaplanMeier method. Survival curves were compared using a standard non-parametric test [6]. The reproducibility of this cytological characterization was also tested among the observers. RESULTS The eighteen cases were firstly classified as R A or R A E B according to the n u m b e r of type I and type II blasts calculated as the mean of the counts of all the observers (called original diagnosis in Table 3). The introduction of type 111 blasts and separation between R A E B 1 and R A E B 11 provides new results (Table 2) and a different distribution of subclasses (Table 3). Reproducibility of the classification in R A , R A E B I, R A E B II, R A E B - t was tested with and without inclusion of type III blasts. The c o n c o r d a n c e was defined as total a g r e e m e n t on the subclassification between original diagnosis and those p r o p o s e d by each observer. T h e c o n c o r d a n c e a m o n g the five observers was 70% at the original diagnosis and 77% at the revised diagnosis (with type III blasts). Based on the original F A B criteria for type I and I I blasts, 7 patients were classified as R A E B I and 10 as R A E B II. Utilizing the type III blast the following alterations occurred: 4 cases r e m a i n e d as R A E B I (one shifting from R A ) ; 4 patients a d v a n c e d to R A E B II; 7 patients m o v e d from R A E B II to R A E B - t . Survival data Survival data were calculated in two different ways. Based on the traditional F A B classification (Table 3), referred to as 'original diagnosis' we c o m p a r e d (Fig. 4) groups I - I V (11 patients) with g r o u p V (7 patients). The estimated median survival time for group V is 7 m o n t h s (standard deviation = 3.9 months) c o m p a r e d to 15 m o n t h s (standard deviation = 2.2 m o n t h s ) , p value = 0.06, using the Mantel-Cox test. The data were reanalyzed based on the introduction of type III blasts into the classification (Table 3, revised diagnosis). T h e revised curves are displayed in Fig. 5. T h e r e are now 3 separate curves
Fill. 1. Hypergranular blast cell (type III) with more than 20 azurophil granules in the cytoplasm.
,, ~.
.~:
FIG. 2. Typical myeloblast (type If) with only some granules.
q
f
FIG. 3. Hypergranular (type III) and agranular (type I) blasts associated with other dysplastic mature cells from a RAEB-t. 1161
1163
The blast cell population TABLE 2. PERCENTAGE OF CELLS COUNTED BY 5 OF TIlE CO-AUTHORS (500 CELLS COUNT) ON CONSECUTIVE FIELDS IN ALL 18 CASES OF M D S . TtlE CASES IIAVE BEEN REARRANGED IN ORDER OF PROGRESSIVE INCREASE IN BLAST CEt.L PERCENTAGE Blast subtype No.
Age
1
II
III
MA
1 2 3 4 5 6 7 16 8 9 15 10 11 12 13 14 17 18
61 50 66 80 56 76 80 45 78 75 59 75 56 51 76 70 74 72
2 I 4 1 5 2 6 3 8 10 10 14 6 6 7 8 14 10
2 5 2 5 3 6 4 7 7 2 3 3 10 6 7 9 5 3
3 4 3 3 6 3 2 7 4 5 5 3 8 11 6 11 7 16
Median =
71
6
5
5.5
F,R*
Survival
Outcome
LT
73 59 55 78 73 64 57 77 70 67 40 39 66 59 66 38 57 30
20 31 36 13 13 25 31 6 11 16 42 41 10 18 14 34 17 41
37 60 15 11 30 24 14 12 6 16 2 7 12 15 4 2 18 2
D A D D D A D D D D D I) D D D D D D
AML2 --AML2 AML2 ---AML2 AML2 AML2 AML2 AML2 AML2 AML2 AML2 ..AML2 AML2
61.5
22
13
M A , m a t u r e granulocytes; E R . erythroid precursors; I,T, leukemic t r a n s f o r m a t i o n : D, d e a d : A, alive.
TABLE 3. |NCIDENCE OF TYPE 111 BI.ASI S AND MODIFICATIONS OF "1It1( ORIGINAl,. CLASSIFI('AIION BY M D S SUBTYPES: R A E B I = BLASTS :>5c'/c AND "< l()c/c; R A E B II = BLASTS > l i C k AND <:20c7c; R A E B - t = BLASTS >20r~ AND < 3 0 ~ Diagnosis Survival m e d i a n No.
Blast I + II
1
4
2 3 4
Subtypes I + II + Ill
Original
Revised
Group
7
RA
I
37
37
I
6 6 6
10 9 9
i I i
I I I
60 15 11
28
!I
5 6 7 16
8 8 ll) 10
14 11 12 17
I I I I
I II II II
30 24 14 12
8 9 15
15 11 13
19 13 18
II II lI
II II II
6 16 2
10 11 12 13 14 17 18
17 16 12 14 17 19 13
20 24 23 20 28 26 29
II II II II II II II
RAEB-t RAEB-t RAEB-t RAEB-t RAEB-t RAEB-t RAEB-t
7 12 15 4 "~ 18 2
III
II
IV
V
1164
J.-E. (.;oAst;t 1.0
:~
0.8
I)IS('USSION 0.6
:i
0
~
04
~
02
I '
I
I
--
I
Group 1-4
J
I
I Group 5 I
O0
,b
2o
3'o 4'o Months
50
60
t:l(;. 4. Kaplan-Meier survival curves for RA + RAEB vs RAEB-t.
( R A E B I, R A E B II, RAEB-t). The median survivals are 15 months (SD: 13 m), 14 months (SD: 3 m) and 7 months (SD: 4 m) respectively. The p value for using the Mantel-Cox test is 0.10. The resorting or reclassification with the type III blast cells improves the median survival of R A E B l from 24 to 31 months and R A E B It from 8.4 to 15.0 months.
1.0
i
~08
t
i i
0
I
o
I .....................
el. ~
et al.
A n examination of the percentage of promyelocytes and other maturing granulocytes for correlation with survival revealed no consistent pattern.
c,")
~ 06
t.~
0.4
"5 E
I I
(.O 0 . 2
I I_
i, .......................
Group 1
Group 2
I
I I
I
00 ' 10
RAEB-! ' 20
30
4'0
' 50
6'0
Months
FK;. 5. Kaplan-Meier survival curves for group 1 (RAEB I), group 2 (RAEB II and RAEB-t) aftcr inclusion of hypcrgranular blast (type III).
Since 1982 several studies on prognosis features and scoring systems have demonstrated the clinical importance of blast cell identitication and its implication on survival duration in MDS [3. 7, l(J]. The aim of the present study was to evaluate a new blast characterization in order to appreciate the dysgranulopoiesis which affects the primary azurophilic granules and its impact on survival. Dysgranulopoiesis is a well-known feature of MDS. Persistance of basophilia and the early development of azurophil granules makes the distinction between myeloblast (type II) and promyelocyte difficult [3.4, 7-9]. In this study we have defined a leukemic cell on the basis of features identical to myeloblasts previously described but with more granules. By applying the criteria of type 1. 11 and III blasts to a series of 18 cases of MDS we have identitied approximately 17c~ of cases whose outcome is worse than other cases of R A E B I with the diagnosis changing to R A E B 11 by the introduction of type III blasts. Moreover. some cases, previously diagnosed as RAEB II are reclassitied as RAEB-(. The shift from the "'progranulocyte'" category is equivalent to a median of 5.5 additional blasts/'cases. The highest percentage of type I11 blasts (11'7,~, 11(;, 16<)~ respectively) occurred in R A E B II. in view of the high risk of leukemic transformation particularly and strikingly FAB M2 in these cases, the granular blasts are not suggestive of increasing differentiation, but rather granule-positive blasts, i.e. leukemic cells. This serves to emphasize thai! some patients with RAEB will have a bad outconle, particularly when the blast percentage exceeds 10%. For those patients who tire reclassified as RAEB-t, and are under the 50yr, the introduction of combination chemotherapy, possibly with recombinant GM-('SF or GCSF might achieve a higher percentage of remissions with resulting improved survival. The survival curve of Mf)S patients has already been related to the number of type 1 blasts [3]. We recently demonstrated [1()] thal type I and lypc II blasts are a major criteria for subclasses and prognosis supports the importance identilication and the potential value of including type 111 blasts. The failure to demonstrate significance at a p value of 0 . 0 5 or less may relate to the relatively small number of cases. ('ertainlv the trend suggests that there m a y ,*'ell be a difference if larger numbers of cases were reviewed.
The blast cell population REFERENCES 1. Bennett J. M.. Catovsky D., Daniel M. T.. Flandrin G., Galton D. A. G., Gralnick tl. R. & Sultan C. (1982) Proposals for the classification of the mvelodysplastic syndromes. Br. J. ttaemat. 51, 189. 2. Bennett J. M.. Catovsky D.. Daniel M. T.. Flandrin G., Galton I). A. G., Gralnick H. R. & Sultan ('. (1985) Proposed revised criteria for the classific~,tion of the acute myeloid leukemia: a report of the FrenchAmerican-British group. Ann. Int. Med. 106, 626. 3. Sanz G. F., Sanz M. A., Vallespi T., Canizo (7.. Torrabedella M., Garcia S., lrriguible D. & San Miguel J. (1989) Two regression models and a scoring system for predicting survival and phmning treatment in mveIodysplastic syndromes. A multivariate analysis of prognostic factors in 370 patients. Blood 74, 3(.)5. 4. Breton-Gorit, s J., ltoussav D. & Dreyfus B. (1975) Partial myeloperoxidase d'eliciency in a case of preleukemia. I. Studies of line structure and peroxidase synthesis of promyelocytes. Br. J. ttaemat. 30, 273. 5. Scoazec J. Y., Imbert M.. Crofts M.. Jouaull t1..
6. 7.
8.
9.
10.
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Juneja S. K., Vernant J. P. & Sultan C. (1985) Myelodysplastic syndrome or acute myeloid leukemia'? A study of 28 cases presenting with borderline features. ('ancer 55, 2390. Cox D. R. & Oakes D. (1984) Analysis ~{ Surt,it,al Data. Chapman and Flail, London, U . K Greenberg P. L. (1983) The smoldering myeloid leukemic states: clinical and biologic features. Blood 61, 1035. Groupe Francais de Morphologie Hematologique (1987) French registry of acute leukemia and mveIodysplastic syndromes. Cancer 60, 1385. Dreyfus B.. Sultan C.. Rochant H., Salmon C., Mannoni P.. ('artron J. P., Boivin P. & Galand C. (1969) Anomalies of blood group antigens and cr.vthrocytes enzymes in two types of chronic relractorv anaemia. Br. J. ttaemat. 16, 303. (ioasgucn J. E., Garand R., Bizet M., Bremond J. I,.. Gardais J., Callat M. P.. Accard F. & Caperon J. (1990) Prognostic factors of myelodysplastic syndromes. A simplified 3D scoring system. I,eukemia Re~. 3, 255.