The Research On The Efficacy Of Ruxolitinib In The Treatment Of Myelofibrosis

Background and purposeMyelofibrosis(MF)is a kind of myeloproliferative tumor(MPN)characterized by clonal proliferation of hematopoietic stem cells.In addition to primary myelofibrosis(PMF),post polycythemia vera myelofibrosis(post-PV MF)and post essential thrombocythemia myelofibrosis(post-ET MF)are also included.The main clinical features of PMF are myelofibrosis,anemia,splenomegaly and disease-related physical symptoms,which are at risk of transformation to acute leukemia.The core pathogenesis is the continuous activation of Janus kinase(JAK)and signal transducer and activator of transcription(STAT)signaling pathways.As the first approved JAK1/2 inhibitor,ruxolitinib can effectively improve the physical symptoms related to MF,reduce the spleen and prolong the survival time.Compared with foreign countries,the application time of ruxolitinib in China is shorter,and further clinical data need to be accumulated.This experiment mainly studies the curative effect of ruxolitinib in improving the physical symptoms and reducing the spleen of MF patients,and discusses the difference of curative effect of patients with different initial doses of ruxolitinib,so as to provide reference and accumulate clinical data for the reasonable and standardized diagnosis and treatment of MF in China.MethodsThis experiment retrospectively analyzed 31 patients with MF who were treated with ruxolitinib in our hospital from January 2016 to April 2019.Among them,there were 11 males(35.48%)and 20 females(64.52%).The median age was 55.7(31-67)years.Collect the clinical data of patients before treatment with ruxolitinib as baseline data,and follow up the patients constitutional symptom load and spleen size before and during treatment.The burden of the patient’s constitutional symptoms is assessed using the Myeloproliferative Tumor Total Symptom Score(MPN-SAF-TSS,MPN-10)once every 4 weeks,and the size of the spleen is assessed by ultrasound or palpation of the subcostal length(Line A and Line B).The constitutional symptom load,changes in spleen size and survival status of patients treated with ruxolitinib for six months and one year were analyzed.The 31 patients were divided into two groups according to the different starting doses of ruxolitinib: the starting dose was10 mg twice a day,hereinafter referred to as the 10 mg group(13 cases);the starting dose was 15 mg twice a day,hereinafter referred to as 15 mg group(18 cases),observe the difference in treatment effect between the two groups.Results(1)Baseline data: The median of the total MPN-10 score of 31 patients was 70 points,and the median of 10 single symptom scores were fatigue(9 points),early satiety(9 points),and abdominal discomfort(9 points),inactivity(9 points),inattention(9 points),night sweats(8 points),itching(8 points),bone pain(8 points),fever(4 points),weight loss(3.26 points).The median length of the spleen under the ribs is 5 cm.(2)The MPN-10 scores of 31 patients all decreased after treatment with ruxolitinib,and the median MPN-10 scores were 50 points and 40 points respectively at half a year and one year after treatment(P<0.05).In the six months and one year of treatment,there were 11 cases(35.48%)and 14 cases(45.2%),respectively,with a decrease of more than 50%.(3)The median percentages of MPN-10 scores of patients in the 10 mg group and 15 mg group decreased from the baseline value at half a year and one year of treatment were 16.8% VS 38.2%,27.7%VS 56.9%,and both were higher than those in the 15 mg group patients in the 10 mg group(P<0.05).(4)In 31 cases of MF,the length of the subcostal spleen was 4 cm after the treatment for half a year and a year,which was lower than the baseline(P>0.05).(5)The median subcostal length of the spleen in the 10 mg and 15 mg groups was 5 cm at baseline,5 cm and 4 cm at the half-year treatment,and the average percentage decrease from baseline was 18.3% and 28.7%,respectively.The annual averages were 4cm,and the average percentage drop from the baseline was 21.7%and 27.5%(P>0.05).(6)The number of patients in the 15 mg group where the baseline value of the spleen subcostal length decreased by over 35% during the six months of treatment was 7 cases(38.9%),4 cases(30.8%)in the greater than 10 mg group,and 8 cases at 1 year of treatment Cases(44.4%),5 cases(38.5%)in the group greater than 10mg(P>0.05).(7)Survival status: As of the end of follow-up,26 patients(83.87%)of 31 patients survived,and 5 patients(16.13%)died.Conclusions1.Ruxolitinib can reduce the MPN-10 score of MF,and the 15 mg group has more declines than the 10 mg group.It is speculated that the efficacy of ruxolitinib in improving the constitutional symptoms of MF may be related to the starting dose.The larger the starting dose,the better the curative effects are.2.Ruxolitinib can reduce the splenic subcostal length of MF,but it has been no obviously relationship with the initial dose.