Chronic myelocytic leukemia (CML) can occasionally occur after long-term chemotherapy for solid tumors; solid tumors secondary to chemotherapy and biotherapy for CML have also been reported. However, concurrence of these two phenomena in an untreated patient has seldom been reported. Herein, we describe the case of a female patient in her early 60 s who was transferred to the liver surgery department after the discovery of a large liver mass and elevated plasma alpha-fetoprotein levels. She was initially diagnosed with liver cancer. Blood tests indicated an increased platelet count (2464 × 109/L). Chromosomal examination from a bone marrow biopsy indicated the presence of the t(9;22) translocation, and subsequent fluorescence in situ hybridization and PCR were positive for the BCR-ABL rearrangement. A diagnosis of CML was made. The patient received hydroxyurea and imatinib to treat CML and underwent subsequent platelet-lowering therapy and a liver biopsy, which suggested moderately poorly differentiated adenocarcinoma or potentially hepatic metastatic carcinoma. However, the patient refused further pathological examination or screening for the site of the primary tumor. She died 6.5 months after discharge. The exact relationship between the two tumors remains unclear, and more patients need to be evaluated.
Chronic myelocytic leukemia (CML) can occasionally occur after long-term chemotherapy for solid tumors; solid tumors secondary to chemotherapy and biotherapy for CML have also been reported. However, concurrence of these two phenomena in an untreated patient has seldom been reported. Herein, we describe the case of a female patient in her early 60 s who was transferred to the liver surgery department after the discovery of a large liver mass and elevated plasma alpha-fetoprotein levels. She was initially diagnosed with liver cancer. Blood tests indicated an increased platelet count (2464 × 109/L). Chromosomal examination from a bone marrow biopsy indicated the presence of the t(9;22) translocation, and subsequent fluorescence in situ hybridization and PCR were positive for the BCR-ABL rearrangement. A diagnosis of CML was made. The patient received hydroxyurea and imatinib to treat CML and underwent subsequent platelet-lowering therapy and a liver biopsy, which suggested moderately poorly differentiated adenocarcinoma or potentially hepatic metastatic carcinoma. However, the patient refused further pathological examination or screening for the site of the primary tumor. She died 6.5 months after discharge. The exact relationship between the two tumors remains unclear, and more patients need to be evaluated.
Chronic myeloid leukemia (CML) is a myeloproliferative disease caused by the
reciprocal translocation of chromosomes 9 and 22, which leads to a chimeric gene
product known as BCR-ABL.
The Bcr-Abl fusion protein possesses constitutively activated Abl tyrosine
kinase activity and activates downstream signaling pathways including Ras/MAPK,
JAK/STAT, and PI3K/AKT, which are responsible for the pathogenesis of CML.
Clinically, CML is considered a triphasic disease, with an initial chronic
phase, an intermediate accelerated phase, and a final, fatal blastic phase.
CML patients are usually characterized by extreme leukocytosis, myelocyte
bulge, basophilia, and eosinophilia in peripheral blood.
Some CML patients can have mild to moderate thrombocytosis, and there are
even individual reports of platelet counts in CML patients reaching over
10000 × 109/L.Concurrent CML and solid tumors have been infrequently reported in four conditions.
The first condition is myeloid sarcoma, commonly known as extramedullary acute
myeloid leukemia and granulocytic sarcoma or chloroma, a tumor composed of myeloid
cells occurring at an extramedullary site.
The most common sites of involvement for these include the small intestine,
bone, skin, and lymph nodes. They can occur in different clinical settings such as
in acute myeloid leukemia (AML) patients as a localized tissue mass, as blast crisis
in CML patients, in leukemic transformation in myelodysplastic syndrome, before AML
onset, and as an isolated neoplasm without evidence of AML.
The second condition is cases of secondary solid tumors reported after CML
treatment including hepatocellular carcinoma (HCC), pulmonary carcinoid, and thyroid
adenocarcinoma.[8-10] The
underlying mechanisms of these cases are unclear but may be related to
chemotherapy-induced DNA damage, multiple genetic alterations, and increasing host
susceptibility to oncogenic viruses due to immunosuppression.
The third condition involves the formation of secondary CML after treatment
for solid tumors, which has been reported in non-small cell lung cancer, thyroid
carcinoma, breast cancer, and gastric adenocarcinoma.[11-13] To date, evidence is lacking
regarding the frequency of therapy-related CML as a complication of cytotoxic
therapy. The fourth condition is that CML can occur after organ transplant, with
more than 30 cases of CML associated with organ transplants having been reported to
date, most of which developed after kidney transplants.[14,15] The development of CML in
this situation may be associated with the post-organ transplant immunosuppressed
state. However, it remains controversial whether the incidence of CML in such
patients is truly higher than that of the general population owing to the limited
number of reported cases.In this case report, we report concurrent liver cancer with CML and extreme
thrombocytosis in an untreated elderly woman.
Case report
An female patient in her early 60s was transferred to our hospital with complaints of
upper abdominal pain accompanied by anorexia for 4 months. Doctors at a local
hospital found a large mass in the patient’s right hepatic lobe by magnetic
resonance imaging (MRI) and elevated plasma alpha-fetoprotein (AFP) levels
(216.5 ng/mL). She was initially diagnosed with liver cancer and admitted to our
liver surgery department. The patient had a 5-year history of hepatitis B (HBV)
infection but had never been treated; she also had a 5-year history of hypertension
and was treated with indapamide tablets. The patient neither smoked tobacco nor
consumed alcohol. There was no notable family medical history, such as cancer.
Physical examination upon admission showed no jaundice, ascites, pedal edema, or
spider nevi, and the liver and spleen were not involved below the costal margin.
There was no obvious enlargement of superficial lymph nodes, and the remaining
physical examination findings were unremarkable. Laboratory tests at admission
(Table 1) showed a
hemoglobin level of 111 g/L, white blood cell count of 7.01 × 109/L, and
platelet count of 2464 × 109/L. Liver function results showed serum
alanine aminotransferase levels of 55 U/L, serum aspartate aminotransferase levels
of 82 U/L, and globulin levels of 69 g/L. HBV-DNA levels were
2.11 × 107 IU/mL, and AFP levels were 308.8 ng/mL. Abdominal color
Doppler ultrasonography showed a large hypoechoic area of approximately 9.5 × 5.7 cm
in the right lobe of the liver, which was irregular in shape, had an unclear
boundary, an uneven internal echo, and the distal part of the right hepatic vein was
not clearly displayed as it was compressed by the mass (Figure 1a). Abdominal contrast-enhanced
computed tomography (CT) scans showed a slightly low-density lesion in the right
lobe of the liver with a maximum diameter of approximately 9.1 × 5.5 cm, slightly
uneven enhancement, and delayed enhancement (Figure 1b, c). The hilar and retroperitoneal
lymph nodes were increased and enlarged. These imaging and biochemical examination
results suggested a neoplastic lesion in the liver, specifically, HCC.
Table 1.
The main laboratory test results at admission.
Patient’s values
Normal range
White blood cells
7.01 × 109/L
3.50–9.50 × 109/L
Neutrophils
3.28 × 109/L
1.80–6.30 × 109/L
Red blood cells
3.71 × 1012/L
3.80–5.10 × 1012/L
Hemoglobin
111 g/L
115–150 g/L
Platelet count
2464 × 109/L
125–350 × 109/L
Aspartate transferase
82 U/L
0–32 U/L
Alanine transaminase
55 U/L
0–33 U/L
Total bilirubin
8.9 μmol/L
3.4–20.5 μmol/L
Lactate dehydrogenase
387 U/L
135–214 U/L
Total protein
92.4 g/L
64–83 g/L
Globulin
64.4 g/L
20–35 g/L
Creatinine
67 μmol/L
45–84 μmol/L
Alpha-fetoprotein
308.8 ng/mL
0–7 ng/mL
Carcinoembryonic antigen
4.69 ng/mL
0–5 ng/mL
Carbohydrate antigen 19-9
0.6 U/mL
0–34 U/mL
Erythrocyte sedimentation rate
95 mm/H
0–22 mm/H
Anti-nuclear antibody
1:320
–
Urine protein
++
–
Hepatitis B virus DNA
2.11 × 107 IU/mL
–
Prothrombin Time
17.3 s
11.5–14.5
Activated partial thromboplastin time
46.8 s
29–42 s
Figure 1.
Imaging features of the liver tumor in the patient. Abdominal color Doppler
ultrasonography (a) showed a large hypoechoic area in the right lobe of the
liver that was irregular in shape, had unclear boundaries, an uneven
internal echo, and the distal part of the right hepatic vein was compressed.
Abdominal contrast-enhanced computed tomography and (b) showed a
9.1 × 5.5-cm slightly low-density lesion in the right lobe of the liver that
had slightly uneven enhancement and delayed enhancement.
The main laboratory test results at admission.Imaging features of the liver tumor in the patient. Abdominal color Doppler
ultrasonography (a) showed a large hypoechoic area in the right lobe of the
liver that was irregular in shape, had unclear boundaries, an uneven
internal echo, and the distal part of the right hepatic vein was compressed.
Abdominal contrast-enhanced computed tomography and (b) showed a
9.1 × 5.5-cm slightly low-density lesion in the right lobe of the liver that
had slightly uneven enhancement and delayed enhancement.The patient was transferred to our hematology department, and further biochemical
examination results showed that the erythrocyte sedimentation rate was 95 mm/H,
beta-2 microglobulin concentration was 4.62 mg/L, and anti-nuclear antibody was
1:320. No M protein was found in the monoclonal gamma globulin disease test. Bone
marrow aspiration and biopsy were performed to examine bone marrow, and the results
showed a hypercellular marrow with marked granulocytic and megakaryocytic
hyperplasia (Figure 2a, b).
Fluorescence in situ hybridization (FISH) analysis with the BCR-ABL
dual fusion probe was performed to detect the BCR and Abl loci. When 200 cells in
interphase were counted, approximately 20% of the cells expressed two fusion
signals, one red signal, and one green signal (Figure 3a), suggesting that the sample was
positive for the BCR-ABL fusion. Chromosome examination also indicated the existence
of the t(9;22) translocation (Figure 3b). Quantitative PCR for the BCR-ABL (p210) fusion transcript
showed that the copy number of the BCR-ABL transcript was 421,662, the ABL
transcript copy number was 384,566, with a ratio of BCR-ABL to ABL transcripts of
109.65%; thus, the international standardization (IS) value was 109.65%. A diagnosis
of chronic-phase CML was then made. The patient received hydroxyurea (1 g po tid)
and imatinib (0.4 g po qd) to treat CML and platelet-lowering therapy with
anagrelide (0.5 mg po bid), bayaspirin (100 mg po qd), and sodium bicarbonate (1 g
po tid). She also received anti-HBV therapy with entecavir (0.5 mg po qd). She
developed agranulocytosis on the seventh day of treatment with hydroxyurea (Figure 4a); thus, we reduced
the hydroxyurea dose and gradually stopped it. She was also treated with an
anti-infection and recombinant human granulocyte stimulating factor injection.
Subsequently, her hemoglobin and platelets gradually decreased (Figure 4b, c). After 14 days of hydroxyurea
treatment, the patient’s platelets returned to within the normal range
(317 × 109/L), and then 3 days later, continued to drop to
21 × 109/L and gradually returned to normal. The main therapeutic
drugs provided during the course of treatment are shown in Figure 4d. The second bone marrow aspiration
and biopsy results both suggested that the erythrocyte and granulocyte series of
bone marrow were suppressed (Figure 2c, d). Quantitative PCR for BCR-ABL showed that the copy number
of the BCR-ABL transcript was 79,692, the ABL transcript copy was 1,282,604, with a
ratio of BCR-ABL to ABL transcript of 6.21%; thus, the IS value was 2.36%. Flow
cytology of the bone marrow suggested an increased proportion of lymphocytes and no
abnormal expression of T lymphocytes, natural killer cells, or monoclonal B
lymphocytes. The proportion of myeloid primordial cells was significantly decreased,
and neutrophils and monocytes were mainly in the mature stage (complete results are
available in Additional file 1).
Figure 2.
Bone marrow aspiration and biopsy during hospitalization. Cytology of bone
marrow at admission (a) showed a large number of platelet aggregations on
bone marrow cytology slide. Megakaryocytes were easily found, and there were
16 granular megakaryocytes and four thromocytogenic megakaryocytes in 20
megakaryocytes. Excessive nuclear lobulation and abnormal nuclear
lobulations were also found. The bone marrow biopsy at admission (b)
suggested that megakaryocytes were clustered or scattered in different cell
sizes, with hypolobation (mononuclear) or multinucleation (two or more round
separated nuclei). The second bone marrow cytology (c) and biopsy (d) after
treatment both showed severely inhibited bone marrow proliferation,
megakaryocytes were easily seen, and hypolobations of megakaryocytes were
also observed.
Figure 3.
Bone marrow genetic testing results. A representative image of fluorescence
in situ hybridization (FISH) analysis with a BCR-ABL
dual fusion probe (a). The red probe represents ABL (chromosome 9), the
green probe BRC (chromosome 22), and the yellow area shows where the two
fluorophores are in close contact, indicating gene fusion and Chromosome
examination (b) indicated the reciprocal translocation of the long arm of
chromosome 22 and the long arm of chromosome 9; arrows indicate the regions
of chromosome translocation.
Figure 4.
Treatments and the response to treatments in this patient. The trends of
white blood cells (WBCs), hemoglobin, and platelets after admission, (a, b,
c respectively) and The abscissa represents the days after admission, and
the ordinates show the values of WBC (×109/L), hemoglobin (g/L),
and platelets (×109/L), respectively. The main drugs and
treatments during hospitalization (d).
rhG-CSF, recombinant human granulocyte-colony stimulating factor; rHuGM-CSF,
recombinant human granulocyte-macrophage colony-stimulating factor; rhIL-11,
recombinant human interleukin 11; CRCs, red blood cells suspension.
Bone marrow aspiration and biopsy during hospitalization. Cytology of bone
marrow at admission (a) showed a large number of platelet aggregations on
bone marrow cytology slide. Megakaryocytes were easily found, and there were
16 granular megakaryocytes and four thromocytogenic megakaryocytes in 20
megakaryocytes. Excessive nuclear lobulation and abnormal nuclear
lobulations were also found. The bone marrow biopsy at admission (b)
suggested that megakaryocytes were clustered or scattered in different cell
sizes, with hypolobation (mononuclear) or multinucleation (two or more round
separated nuclei). The second bone marrow cytology (c) and biopsy (d) after
treatment both showed severely inhibited bone marrow proliferation,
megakaryocytes were easily seen, and hypolobations of megakaryocytes were
also observed.Bone marrow genetic testing results. A representative image of fluorescence
in situ hybridization (FISH) analysis with a BCR-ABL
dual fusion probe (a). The red probe represents ABL (chromosome 9), the
green probe BRC (chromosome 22), and the yellow area shows where the two
fluorophores are in close contact, indicating gene fusion and Chromosome
examination (b) indicated the reciprocal translocation of the long arm of
chromosome 22 and the long arm of chromosome 9; arrows indicate the regions
of chromosome translocation.Treatments and the response to treatments in this patient. The trends of
white blood cells (WBCs), hemoglobin, and platelets after admission, (a, b,
c respectively) and The abscissa represents the days after admission, and
the ordinates show the values of WBC (×109/L), hemoglobin (g/L),
and platelets (×109/L), respectively. The main drugs and
treatments during hospitalization (d).rhG-CSF, recombinant human granulocyte-colony stimulating factor; rHuGM-CSF,
recombinant human granulocyte-macrophage colony-stimulating factor; rhIL-11,
recombinant human interleukin 11; CRCs, red blood cells suspension.The patient underwent a liver biopsy when her routine blood results returned to near
normal, and hematoxylin and eosin staining suggested heterotypic adenoid and solid
cell nests with necrosis in the chronic inflammatory liver tissue (Figure 5a). The Ki-67 index
was approximately 30% to 40% (Figure 5b). Immunohistochemical studies showed positive staining for
VILLIN, CK7, and EMA but negative staining for hepatocytes, Glypican-3, Arginasc1,
AFP, CK19, CK20, CDX2, TTF-1, NapsinA, PAX8, ER, PR, and GATA3 (Figure 5c–r). The pathologists concluded
that the patient had moderately poorly differentiated adenocarcinoma, and hepatic
metastatic carcinoma could not be excluded.
Figure 5.
Hematoxylin and eosin (HE) and immunohistochemical staining of puncture liver
tissues. HE staining of liver biopsy specimen (a) showed heterotypic adenoid
and solid cell nests with necrosis in the chronic inflammatory liver tissue
(magnification: 100×). The Ki-67 labeling index was approximately 30% to 40%
(b) and Immunohistochemical staining for CK7, EMA, VILLIN, hepatocytes,
Glypican-3, Arginasc1, AFP, CK19, CK20, CDX2, TTF-1, NapsinA, PAX8, ER, PR,
and GATA3 (c–r, respectively) (magnification: 100×).
Hematoxylin and eosin (HE) and immunohistochemical staining of puncture liver
tissues. HE staining of liver biopsy specimen (a) showed heterotypic adenoid
and solid cell nests with necrosis in the chronic inflammatory liver tissue
(magnification: 100×). The Ki-67 labeling index was approximately 30% to 40%
(b) and Immunohistochemical staining for CK7, EMA, VILLIN, hepatocytes,
Glypican-3, Arginasc1, AFP, CK19, CK20, CDX2, TTF-1, NapsinA, PAX8, ER, PR,
and GATA3 (c–r, respectively) (magnification: 100×).The patient refused further pathological examination or screening for the primary
tumor site and asked to be discharged from the hospital. She continued to take
imatinib after discharge at a dosage of 0.4 g per day. However, she reduced the
dosage by herself to 0.1 g per day due to a severe gastrointestinal reaction. During
the fourth month after discharge, the patient’s platelet count was in the normal
range (272 × 109/L), while color Doppler ultrasonography showed that the
liver tumor had enlarged (9.8 × 7.3 cm). She died 6.5 months after discharge, and
the exact cause of her death is unclear.We have de-identified all patient details and ensured that the reporting of this case
conforms to CARE guidelines.
Discussion
CML is a clonal disorder of hematopoietic stem cells that is characterized by the
presence of the Philadelphia chromosome t(9:22) and manifests as an increased
myeloid cell count, marked leukocytosis, myelocyte bulge, basophilia, eosinophilia,
and normal to mild thrombocytosis in peripheral blood.
Rare cases of CML may present with isolated, marked thrombocytosis, which is
defined as a platelet count greater than 1000 × 109/L.
Sora et al.
evaluated the marked thrombocytosis associated with CML in a large series of
patients from 16 different Italian hematological centers treated between January
2002 and December 2015. Among the 1591 CML patients, 87 with extreme thrombocytosis
were identified, with platelet counts ranging from 1054 × 109/L to
4720 × 109/L. CML patients with atypical clinical features and severe
thrombocytosis often mimic the features of essential thrombocytosis (ET), as
reported previously.
In our case, the patient's platelet count was as high as
3622 × 109/L, but her erythrocyte and granulocyte series in
peripheral blood were generally normal. However, FISH, chromosome examination, and
RT-PCR confirmed the diagnosis of CML. Moreover, bone marrow aspiration and biopsy
revealed megakaryocytes that were smaller than normal cells and with typical
hyperlobated round nuclei. Therefore, we and other researchers propose that every
patient with ET should be tested for the Philadelphia chromosome to avoid missing
CML diagnoses.The main pathogenesis of CML is the reciprocal translocation between chromosomes 9
and 22, which leads to the tyrosine kinase coding gene ABL of chromosome 9 fusing
into the BCR region of chromosome 22. An important result of this chromosome
translocation is the product of the ABL-BCR fusion gene, which encodes a deregulated
tyrosine kinase, resulting in manifestations of CML. Inhibiting the oncogenic
expression and protein function of BCR-ABL are the primary treatments for CML on the
basis of its pathogenesis. Bcr-Abl tyrosine-kinase inhibitors (TKIs) are the
first-line therapy for CML; among which, imatinib is one of the most classic
first-line drugs. In the recent study by Sora et al., the majority
of patients received pretreatment with hydroxycarbamide and were then treated with
TKIs (63 patients received imatinib, 16 received dasatinib, and 8 were given
nilotinib), and 87% of patients achieved a complete cytogenetic response (CCyR) or a
major molecular response (MMR) after 12 months of treatment.
In our case, the patient received pretreatment with hydroxycarbamide and
platelet-lowering therapy with anagrelide, but it did not achieve a relevant
reduction in platelet count. However, when imatinib therapy was started, the
platelet count rapidly decreased to within the normal range. At the 4-month
follow-up after discharge, her platelet count remained in the normal range.Another issue in our report is the concurrent solid tumor with CML in this one
patient. The abnormally elevated AFP levels, liver masses on CT imaging, and past
history of HBV infection all support the clinical diagnosis of a liver tumor,
particularly HCC. However, continuous monitoring of tumor markers revealed a
downward trend in AFP levels (Additional file 2). Pathological diagnosis of the
liver biopsy suggested moderately poorly differentiated adenocarcinoma, and it is
also possible that the tumor was a metastatic liver tumor. However, neither
abdominal enhanced CT scans, chest CT scans, nor gastroscopy investigations
(Additional file 3) showed tumors in other parts of the abdomen. Owing to the
particularity of liver tumors concurrent with hematological tumors, we consulted the
literature and found some other reports of liver tumors coexisting with
hematological tumors. Katoh et al. reported the case of a
55-year-old Japanese man with CML who had received an alkylating agent for 16 years
and was later diagnosed with HCC with clinically evident splenic metastases.
This was the first report in the literature of HCC associated with CML. The
authors suggested that long-term chemotherapy-induced DNA damage may have endowed
HCC with an aggressive proliferative potential.
Ansari et al. presented the case of a 72-year-old man
diagnosed with CML who subsequently presented with a liver mass that was
pathologically diagnosed as histiocytic sarcoma (HS).
The liver mass retained the BCR-ABL1 translocation, suggesting clonality
between the CML and HS. Therefore, the authors proposed that the concurrent
expression of immunoglobulin heavy (IGH)-/light-chain rearrangements or cytogenetic
markers common to primary CML suggested an evolutionary mechanism involving lineage
switching that was potentially affected by genetic or epigenetic factors that may
have occurred at the level of a progenitor or in the malignant cell itself.
Myeloid sarcoma is a rare extramedullary presentation of neoplastic myeloid
cells that may occur before, concurrent with, or after the diagnosis of
myeloproliferative disorders, such as AML or CML. Norsworthy et al.
reviewed 51 cases of biopsy-proven myeloid sarcoma involving the liver, biliary tree
or pancreas,
and most cases presented with systemic disease, mainly associated with AML
and CML. The main symptoms included jaundice, right upper quadrant abdominal pain,
fatigue, anorexia, nausea, and vomiting. Many patients were initially diagnosed with
cholecystitis, pancreatitis, or carcinoma, especially those with unknown
hematological diseases, and underwent surgery. As immunohistochemistry confirmed,
the most commonly expressed cell surface markers of myeloid sarcoma in these
patients were myeloperoxidase (63%), CD68 (40%), CD45 (30%), CD34 (30%), CD43 (30%),
CD117 (28%), CD33 (15%), lysozyme (15%), and CD13(8%).
In this case, more immunohistological tests could have been performed to
better diagnose the patient; unfortunately for our patient, there were no additional
samples for further immunohistochemical detection of myeloid sarcoma markers.
Although the platelet count was reduced to a normal range, imatinib therapy did not
reduce the size of the liver tumor.In summary, we presented a rare case of liver cancer concurrent with CML and extreme
thrombocytosis in an elderly patient. However, the exact pathological relationship
between the liver cancer and CML in this case is unknown.Click here for additional data file.Supplemental material, sj-pdf-1-imr-10.1177_03000605221123684 for Liver cancer
concurrent with chronic myelocytic leukemia and extreme thrombocytosis: a rare
case report by Ping Han, Zhi-Qiang Han, Xia Mao, Jin Wang, Qin-Lu Li, Min Xiao,
Li Meng, De-An Tian and Zhen-Ya Hong in Journal of International Medical
ResearchClick here for additional data file.Supplemental material, sj-pdf-2-imr-10.1177_03000605221123684 for Liver cancer
concurrent with chronic myelocytic leukemia and extreme thrombocytosis: a rare
case report by Ping Han, Zhi-Qiang Han, Xia Mao, Jin Wang, Qin-Lu Li, Min Xiao,
Li Meng, De-An Tian and Zhen-Ya Hong in Journal of International Medical
ResearchClick here for additional data file.Supplemental material, sj-pdf-3-imr-10.1177_03000605221123684 for Liver cancer
concurrent with chronic myelocytic leukemia and extreme thrombocytosis: a rare
case report by Ping Han, Zhi-Qiang Han, Xia Mao, Jin Wang, Qin-Lu Li, Min Xiao,
Li Meng, De-An Tian and Zhen-Ya Hong in Journal of International Medical
Research
Authors: Joel J Gagnier; Gunver Kienle; Douglas G Altman; David Moher; Harold Sox; David Riley Journal: Headache Date: 2013 Nov-Dec Impact factor: 5.887