The Role Of Splenectomy In The Treatment Of Myelofibrosis
Authors: Melikyan Anait L. , Kovrigina Alla M. , Sokolova Manana A. , Kolosova Ludmila U. , Silaev Maksim A. , Gilyazitdinova Elena A. , Subortseva Irina N. , Gemdjian Eduard G. , Karagulyan Suren R , Savchenko Valeri G. 
Published: October 2019

Abstract

Background
Splenectomy (SE) at the Myelofibrosis (MF) is one of the difficult operations on the techniques and perioperative complications. There are a lot of complications such as inflammatory and adhesive processes, a massive bleeding associated with disorders of hemostasis in thrombocytopenia or thrombocytosis, enlargement of varicose veins, concomitant pathology. A SE doesn’t cure myelofibrosis but may be performed in some cases. Success is unpredictable, and the operative mortality of SE is on the order of 10%.

Objectives
Evaluate the clinical and hematologic SE efficiency in patients with MF, resistant to traditional treatment.

Patients and methods
We analyzed the medical case history of 52 patients with MF, which were observed in the National Research Center for Hematology from 2004 to 2013. All patients were performed SE. 47 patients diagnosed with primary MF, and 4 – post-polycitaemic MF and 1 patient post-trombocitaemic MF. PMF was diagnosed according to the criteria established by WHO (2008), which include bone marrow fibrosis, and splenomegaly leyko-eritroblastosis in peripheral blood. The average age at diagnosis was 47 years (24 – 78 years), and before the SE – 53 (25 – 79 years). Women and men ratio was 1.3:1. According to the predictive model of the Dynamic International Prognostic Score System - (DIPSS) 38 (73%) patients before the SE attributed to intermediate risk 2, 14 (27%) patients – high risk. BCR-ABL gene not found a single patient, and the gene mutation JAK2V617F at different stages of the disease is detected in 53% of cases. Genetic adverse factors are not taken into account because of the small number of studies. Massive and huge splenomegaly was present in 37 (71%) patients. Spleen weight 0.9 to 2.9 kg is removed in 15 (29%) patients, from 3 to 7 kg is removed in 35 (67%) patients. In two cases, removal of the spleen weight of 10 and 11 kg. Statistical analysis were done using SAS 9.3 and JMP 10.0 (SAS Institute Inc., Cary, NC).

Results
Disease duration was about 76 months and ranged from 1 to 240 months. Surgical complications occurred in 21 patients, including bleeding 3, thrombosis 1, infection 2. Surgical complications from SE in intra-and early postoperative period was 8% from 1978 to 2003. Surgical complications from SE in intra-and early postoperative period was not fixed from 2004 to 2013. After SE complications were hepatomegaly, resistant thrombocytosis (platelet count ≥ 600 × 109/L), leukocytosis (white blood cell count greater than 10 x 109/l) and blast transformation of the disease. More than 80% of patients after SE had no symptoms of intoxication. 22 patients with MF had transfusion dependent anemia, 11 (50%) had disappeared transfusion requirements after SE in and the effect lasted for about a year. Only 4 of the 15 patients with thrombocytopenia who underwent SE due to refractory thrombocytopenia were observed a significant increase in platelet count above 100h109 / L, for an average of 6 months. The possibility of the resumption of long-term cytoreductive therapy appeared in 30 (58%) patients. Currently alive 19 (37%) patients, mean follow-up was 37 months (4 to 72 months) after the SE and of 105 (12-264) months after diagnosis. 33 (63%) patients died during the observation period after SE (1 – 84 months, mean – 27 months). Among these, 27 (82%) patients died of transformation disease and 6 (18%) died of comorbidity. 19 (37%) patients, with a mean follow-up of 37 months after SE (from 4 to 72 months) continue treatment with hydroxyurea. Median survival after SE is 3 years (Figure 1), with a median overall survival - 11 years (Figure 2).

Conclusion
Despite the potential complications SE is an effective palliative method for patients with MF in the absence of leukemic progression. SE indicated in patients with drug refractory MF, acute constitutional symptoms, anemia, transfusion-dependent, and portal hypertension. Modern methods of surgery, as well as supporting therapy in the perioperative period can safely perform the SE.

Disclosures:
No relevant conflicts of interest to declare.