Histamine and Bone Pain Association in Participants with Breast Cancer Metastatic in the Bone

PRIMARY OBJECTIVES:

I. To correlate levels of histamine in plasma with pain scores in patients with bone metastases from breast cancer that have or have not been treated with palliative radiotherapy.

SECONDARY OBJECTIVES:

I. To perform exploratory studies with additional markers not mentioned, including calcitonin gene-related peptide (CGRP), stem cell factor (SCF), angiotensin II (Ang II) substance P, angiotensin 1-7 (Ang1-7), may be performed at the investigator’s discretion.

II. To perform next generation ribonucleic acid (RNA) sequences using the whole blood to determine whether histamine system is involved in the development of cancer-induced bone pain (CIBP).

III. To assess the impact of pain response after radiotherapy on bone structural properties such as bone mineral density and cortical thickness, and patient quality of life, physical and psychological function.

EXPLORATORY OBJECTIVES:

I. To compare primary and secondary outcomes between patients who do not plan on receiving radiation therapy for bone pain with baseline visual analog scale (VAS) pain scale =< 5 (zero to mild pain) (Group 1A) and baseline VAS pain scale > 5 (moderate to severe pain) (Group 1B).

II. To compare primary and secondary outcomes between patients with baseline VAS pain scale > 5 who do not plan on receiving radiation therapy for bone pain (Group 1B) and patients with bone pain (VAS pain score > 5) who do plan on receiving radiation therapy for bone pain (Group 2).

III. To compare primary and secondary outcomes between patients who receive pain relief from radiation (Group 2A) and patients who receive no pain relief from radiation (Group 2B).

OUTLINE:

Participants undergo collection of blood samples for histamine level analysis via enzyme-linked immunosorbent assay (ELISA).

After completion of study, participants are followed up at 1, 3, and 6 months.