186Re-etidronate in breast cancer patients with metastatic bone pain.
The aim of this study was to evaluate the efficacy of 186Re-1,1-hydroxyethylidene diphosphonate (etidronate) in breast cancer patients with painful bone metastases.


METHODS
Thirty patients with advanced breast cancer who had metastatic bone pain were treated with 186Re-etidronate using different dosages in a noncomparative, open-label study. Twenty-four patients were evaluated for efficacy (6 patients had incomplete datasets). Dosages varied from 1295 to 2960 MBq (35 to 80 mCi). Efficacy was evaluated according to the multidimensional pain model using a paper-and-pencil diary. The diary was kept twice daily for 8-10 wk (2 wk before through 6-8 wk after 186Re-etidronate treatment). Response was determined with a strict criteria, in which pain intensity (PI), medication index (MI) and daily activities (DA) were core determinants. Response was defined as: (a) Reduced PI > or = 5% while MI and DA were at least constant; or (b) Reduced PI <25% in combination with improvement of MI or DA > or = 25%, without worsening of either factor. Duration of response should always exceed a minimum of 2 wk.


RESULTS
Fifty-eight percent (n = 14) of all patients reported a response. The maximum follow-up period was 8 wk. Duration of response ranged from 2 to 8 wk (mean 4 wk). Patients (14/24) not only experienced considerable pain reduction, but in 12 patients this was also accompanied by noteworthy reduction in MI (> or = 25%). No clear dose-response relationship was found.


CONCLUSIONS
With strict pain assessment criteria, 186Re-etidronate showed a response of 58% in the palliative treatment of metastatic bone pain originating from breast cancer.
Han
S H
SH
Department of Nuclear Medicine, University Hospital Utrecht, The Netherlands.
Zonneberg
B A
BA
de Klerk
J M
JM
Quirijnen
J M
JM
van het Schip
A D
AD
van Dijk
A
A
Blijham
G H
GH
van Rijk
P P
PP
D001859:Bone Neoplasms / Q000503:physiopathology / Q000532:radiotherapy* / Q000556:secondary*; D001943:Breast Neoplasms / Q000473:pathology*; D012968:Etidronic Acid / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D009942:Organometallic Compounds; D010148:Intractable Pain / Q000532:radiotherapy*; D010166:Palliative Care / Q000379:methods*; D011868:Radioisotopes / Q000627:therapeutic use*; D012211:Rhenium / Q000627:therapeutic use*
D009942:Organometallic Compounds; D011868:Radioisotopes; C101598:rhenium-186 HEDP; D012211:Rhenium; D012968:Etidronic Acid