DISCUSSION

Splenomegaly and associated symptoms such as upper abdominal/left flank pain, early satiety, malaise, bleeding, and features of cytopenias require intervention apart from addressal of primary etiology. Symptoms caused are by either the mass effect or sequestration of blood elements owing to congestive splenomegaly [2]. Spleen radiotherapy is carried out using external beam technique with variable total dose, dose per fraction and treatment schedules. Available literature suggests total doses in the range of 0.15-30.5 Gy and fraction doses in the range of 0.1-2.5 Gy have been used respecting the radiation sensitivity of spleen, primary etiology, co-morbidities and dose at which palliation is achieved [3]. The said patient had grade-3 anemia/neutropenia and grade-4 thrombocytopenia at baseline apart from upper abdominal pain and malaise secondary to CLD and PH other than existing co-morbidities [4]. Though young she was planned for a total splenic irradiation dose of 5Gy in 10 fractions delivered twice weekly owing to the concerns for adverse events mainly hematological [5]. The EBRT technique used was VMAT for better conformation of doses to spleen rather than surrounding structures.

It was interesting to observe the hemoglobin value increasing almost in a linear trend following each fraction of EBRT to a total increase of 1.6 g/dl in 34 days. In a case series reported by Liu et al. [6] it was reported that the hemoglobin level didn’t raise after splenic irradiation (12Gy/8Fractions, 5 fractions per week) in any of the patients (0/5) with Liver cirrhosis and portal hypertension⁶. While Bruns et al. reported improved hemoglobin in 3 out of 5 patients with splenomegaly (benign etiology) treated to a total dose of 3Gy in 0.5Gy per fraction delivered 2-3 times per week [7]. In our study the trendlines of both TLC and ANC followed the average values of two consecutive readings and it was seen that following each radiotherapy fraction the TLC values dipped for a brief duration ranging from 12-72 h followed by an increase; duration of which ranged from 12-24 h. The graph of ANC closely hugged that of TLC and the variation too graphically appeared similar (Figure 3). Liu et al. [6] reported decline in TLC count in 3 out of 5 patients at the end of follow up (in one case count wasn’t reported), Bruns et al. [7] suggested decrease in TLC count in 2 out of 5 patients. Reported benefit in platelet count were noted in all 5 patients by Liu et al. whereas 3 out of 5 patients in series by Burns et al. Our platelet count analysis suggested a decrease in count (median 3000/mm³) following each time the fractional dose is delivered (median time 12 h from dose) followed by a hike. The nadir value of platelet reported were 4000/mm³ which was manifested in the form of petechiae and ecchymosis but no episodes of life-threatening hemorrhagic event was noted. Platelets were transfused only when the counts went below 5000/mm³. The last collected count of platelet/ANC (48 h after last fraction of EBRT) were 3500/mm³, 290/mm³ higher than baseline. The maximum decrease in different corpuscular parameters following each fraction of radiotherapy as compared to value at the time of delivery of dose occurred at a median time of 30.1-35.5 h. Mean, median, standard deviation, range of blood parameters are reported in Table 1.

Available literature in splenic irradiation suggests a partial or complete benefit for symptoms/lab abnormalities was obtained in 85-90% of treated patients [8]. In our study the patient was completely relieved of pain accompanied by 4cm decrease in size of splenomegaly (as measured in maximum cranio-caudal direction by CT image) and improvement in both anemia as well as thrombocytopenia. Except for transient decrease in platelet counts and resulting ecchymosis no other skin/gastrointestinal/infectious complications occurred during the course of splenic irradiation in the said patient.

CONCLUSION

Splenic irradiation is a safe and effective method to improve splenomegaly and resultant hypersplenism as a result of benign etiology even in patient with multiple co-morbidity. The dynamics of change in different blood parameters may be represented by linearly increasing hemoglobin, waning and waxing TLC, ANC and platelets following a certain trend. Validation of these trends will need observation in higher number of patients and using different radiotherapy dose/fractionation scheme.