Pain Relief Associated with Radiotherapy for Symptomatic Vertebral Lesions in Multiple Myeloma- A Retrospective Analysis

Introduction: Multiple Myeloma is the most common Plasma cell disorder in India. It is primarily involving the Bone Marrow and so most patients have lytic bone lesions. It is a systemic disease and chemotherapy is the primary treatment. However, as the disease involves the bone marrow or bone, lesions may progress and cause bone pain, fractures, spinal cord/nerve compression, and may be associated with soft-tissue masses posing a higher risk to patients. These local lesions require more local therapy such as surgical excision and/or radiotherapy for symptomatic relief and/or to prevent further local progression. Radiotherapy (RT) alone is a definitive treatment choice for Solitary Plasmacytoma where moderate doses of radiation are good enough for cure (5). Radiotherapy has also an important role in the management of multiple myeloma by reducing painful osteolytic process and improving recalcification. Radiotherapy prevents pathologic fractures, prevents impending paraplegia, controls serious bone pain and reduces analgesic usage. Objective To assess the pain relief associated with palliative radiotherapy for Symptomatic Vertebral Lesions in Multiple Myeloma. Materials and Method: After getting ethical clearance all patients registered in Radiotherapy department during the period January 2017 to December 2019 for THREE years with diagnosis of Multiple Myeloma and having vertebral lesion were enrolled for the study. The osteolytic vertebral lesion must be confirmed by X-ray or CAT scan or MRI evaluation as the case may be. All radiological assessments should have been done prior to the Radiotherapy treatment. Radiation treatment was delivered using Linear Accelerator Varian Clinac IX with Megavoltage beams and appropriate Photon energy. Numerical Pain Rating Pain Scale (NPRS) was used for pain level evaluation (7). A pain score ≤ 4 was classified as mild, 5-7 as moderate and severe if the pain score was ≥ 8. All patients were evaluated in terms of their pain intensity before Radiotherapy (called as basal pain score) by using NPRS and they were re-evaluated 30-45 days after their radiation treatment by using NPRS. Result: A total of 95 patients who fulfilled the inclusion criteria were enrolled in the study. Of the 95 patients there were 54 males and 41 females in the ratio 1.31: 1. One male patient had cervical and thoracic vertebral lesions and the Radiation treatment could not be completed because of his deteriorating performance status and was excluded from the study. There were 102 vertebral segments of which 2 were excluded. The remaining 100 vertebral segments were Cervical 7, Thoracic 45, and Lumbosacral 48. The main symptom was pain which was present in all the patients. Neurological symptoms such as Paresthesia, difficulty to walk, weakness of lower limbs was seen in 34 (36.17%) patients. It was noted that 4 (4.25%) patients had paraspinal soft tissue component as noted in the radiological investigation. Numerical Pain Rating Pain Scale (NPRS) was used for pain level evaluation in 94 patients. Number of patients with No to Mild pain was 0; patients with moderate pain score was 4 (4.26%); and patients with severe pain score was 90 (95.74%). After Radiation treatment, pain was reassessed using NPRS and it was found that patients with Mild to No pain was 90 (95.74%); patients with moderate pain score was 3 (3.2%); and patients with severe pain score was 1 (1.06%). Using the paired student T-test statistical analysis on Excel sheet it was found that the Mean Difference was -6.4, Standard deviation 1.607 which gave a highly significant p value <0.0001. Patient who got more than 5 point reduction in NPRS scale was 89 (94.68%) and those with less than 5 point reduction in pain scale was 4 (4.26%). 1 (1.06%) had progressive weakness of lower limbs and had to undergo spine fixation surgery. Conclusion: Radiotherapy is an excellent modality of treatment for significant pain reduction in patients having symptomatic vertebral lesion in Multiple Myeloma. It was noticed that most of the patients post RT required nil to minimum analgesics for pain relief. Although the pain relief in patients who had paraspinal soft tissue component was not much as the other patients.