Juvenile Myelomonocytic Leukemia in Turkey: A Retrospective Analysis of Sixty-five Patients.
OBJECTIVE
This study aimed to define the status of juvenile myelomonocytic leukemia (JMML) patients in Turkey in terms of time of diagnosis, clinical characteristics, mutational studies, clinical course, and treatment strategies.


METHODS
Data including clinical and laboratory characteristics and treatment strategies of JMML patients were collected retrospectively from pediatric hematology-oncology centers in Turkey.


RESULTS
Sixty-five children with JMML diagnosed between 2002 and 2016 in 18 institutions throughout Turkey were enrolled in the study. The median age at diagnosis was 17 months (min-max: 2-117 months). Splenomegaly was present in 92% of patients at the time of diagnosis. The median white blood cell, monocyte, and platelet counts were 32.9x109/L, 5.4x109/L, and 58.3x109/L, respectively. Monosomy 7 was present in 18% of patients. JMML mutational analysis was performed in 32 of 65 patients (49%) and PTPN11 was the most common mutation. Hematopoietic stem cell transplantation (HSCT) could only be performed in 28 patients (44%), the majority being after the year 2012. The most frequent reason for not performing HSCT was the inability to find a suitable donor. The median time from diagnosis to HSCT was 9 months (min-max: 2-63 months). The 5-year cumulative survival rate was 33% and median estimated survival time was 30±17.4 months (95% CI: 0-64.1) for all patients. Survival time was significantly better in the HSCT group (log-rank p=0.019). Older age at diagnosis (>2 years), platelet count of less than 40x109/L, and PTPN11 mutation were the factors significantly associated with shorter survival time.


CONCLUSIONS
Although there has recently been improvement in terms of definitive diagnosis and HSCT in JMML patients, the overall results are not satisfactory and it is necessary to put more effort into this issue in Turkey.
Dokuz Eylül University Faculty of Medicine, Department of Pediatric Hematology, İzmir, Turkey.
Özlem
Ö
Tüfekçi
Gazi University Faculty of Medicine, Department of Pediatric Hematology, Ankara, Turkey.
Ülker
Ü
Koçak
Gazi University Faculty of Medicine, Department of Pediatric Hematology, Ankara, Turkey.
Zühre
Z
Kaya
Gazi University Faculty of Medicine, Department of Pediatric Hematology, Ankara, Turkey.
İdil
İ
Yenicesu
Ondokuz Mayıs University Faculty of Medicine, Department of Pediatric Hematology, Samsun, Turkey.
Canan
C
Albayrak
Ondokuz Mayıs University Faculty of Medicine, Department of Pediatric Hematology, Samsun, Turkey.
Davut
D
Albayrak
Dokuz Eylül University Faculty of Medicine, Department of Pediatric Hematology, İzmir, Turkey.
Şebnem
Ş
Yılmaz Bengoa
Erciyes University Faculty of Medicine, Department of Pediatric Hematology and Oncology, Kayseri, Turkey.
Türkan
T
Patıroğlu
Erciyes University Faculty of Medicine, Department of Pediatric Hematology and Oncology, Kayseri, Turkey.
Musa
M
Karakükçü
Erciyes University Faculty of Medicine, Department of Pediatric Hematology and Oncology, Kayseri, Turkey.
Ekrem
E
Ünal
Ankara University Faculty of Medicine, Department of Pediatric Hematology and Oncology, Ankara, Turkey.
Elif
E
Ünal İnce
Ankara University Faculty of Medicine, Department of Pediatric Hematology and Oncology, Ankara, Turkey.
Talia
T
İleri
Ankara University Faculty of Medicine, Department of Pediatric Hematology and Oncology, Ankara, Turkey.
Mehmet
M
Ertem
İstanbul University Cerrahpaşa Faculty of Medicine, Department of Pediatric Hematology and Oncology, İstanbul, Turkey.
Tiraje
T
Celkan
İstanbul University Cerrahpaşa Faculty of Medicine, Department of Pediatric Hematology and Oncology, İstanbul, Turkey.
Gül Nihal
GN
Özdemir
Kocaeli University Faculty of Medicine, Department of Pediatric Hematology, Kocaeli, Turkey.
Nazan
N
Sarper
Ankara Children's Hematology and Oncology Training and Research Hospital, Ankara, Turkey.
Dilek
D
Kaçar
Ankara Children's Hematology and Oncology Training and Research Hospital, Ankara, Turkey.
Neşe
N
Yaralı
Ankara Children's Hematology and Oncology Training and Research Hospital, Ankara, Turkey.
Namık Yaşar
NY
Özbek
Akdeniz University Faculty of Medicine, Department of Pediatric Hematology and Oncology, Antalya, Turkey.
Alphan
A
Küpesiz
Dr. Behçet Uz Children Training and Research Hospital, Clinic of Pediatric Hematology and Oncology, İzmir, Turkey.
Tuba
T
Karapınar
Dr. Behçet Uz Children Training and Research Hospital, Clinic of Pediatric Hematology and Oncology, İzmir, Turkey.
Canan
C
Vergin
Necmettin Erbakan University Meram Faculty of Medicine, Department of Pediatric Hematology, Konya, Turkey.
Ümran
Ü
Çalışkan
Necmettin Erbakan University Meram Faculty of Medicine, Department of Pediatric Hematology, Konya, Turkey.
Hüseyin
H
Tokgöz
Uludağ University Faculty of Medicine, Department of Pediatric Hematology, Bursa, Turkey.
Melike
M
Sezgin Evim
Uludağ University Faculty of Medicine, Department of Pediatric Hematology, Bursa, Turkey.
Birol
B
Baytan
Uludağ University Faculty of Medicine, Department of Pediatric Hematology, Bursa, Turkey.
Adalet Meral
AM
Güneş
Ege University Faculty of Medicine, Department of Pediatric Hematology, İzmir, Turkey.
Deniz
D
Yılmaz Karapınar
Şişli Hamidiye Etfal Training and Research Hospital, Clinic of Pediatric Hematology and Oncology, İstanbul, Turkey.
Serap
S
Karaman
Bahçeşehir University Faculty of Medicine, Department of Pediatric Hematology and Oncology, İstanbul, Turkey.
Vedat
V
Uygun
Bahçeşehir University Faculty of Medicine, Department of Pediatric Hematology and Oncology, İstanbul, Turkey.
Gülsun
G
Karasu
Bahçeşehir University Faculty of Medicine, Department of Pediatric Hematology and Oncology, İstanbul, Turkey.
Mehmet Akif
MA
Yeşilipek
Marmara University Faculty of Medicine, Department of Pediatric Hematology and Oncology, İstanbul, Turkey.
Ahmet
A
Koç
Karadeniz Technical University Faculty of Medicine, Department of Pediatric Hematology and Oncology, Trabzon, Turkey.
Erol
E
Erduran
Tepecik Training and Research Hospital, Clinic of Pediatric Hematology and Oncology, İzmir, Turkey.
Berna
B
Atabay
Tepecik Training and Research Hospital, Clinic of Pediatric Hematology and Oncology, İzmir, Turkey.
Haldun
H
Öniz
Dokuz Eylül University Faculty of Medicine, Department of Pediatric Hematology, İzmir, Turkey.
Hale
H
Ören
D001706:Biopsy; D002675:Child, Preschool; D003131:Combined Modality Therapy; D005260:Female; D005820:Genetic Testing; D006801:Humans; D007223:Infant; D054429:Leukemia, Myelomonocytic, Juvenile / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology / Q000628:therapy; D008297:Male; D062486:Public Health Surveillance; D012189:Retrospective Studies; D016019:Survival Analysis; D063189:Symptom Assessment; D014421:Turkey / Q000453:epidemiology
Hematopoietic stem cell transplantation; Juvenile myelomonocytic leukemia Turkey.