Dose esclation in radioimmunotherapy based on projected whole body dose

Journal Article · Sun May 01 04:00:00 EDT 1994 · Journal of Nuclear Medicine

OSTI ID:198092

Wahl, R L; Kaminski, M S; Regan, D ^[1]

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1. Univ. of Michigan Medical Center, Ann Arbor, MI (United States); and others

A variety of approaches have been utilized in conducting phase I radioimmunotherapy dose-escalation trials. Escalation of dose has been based on graded increases in administered mCi; mCi/kg; or mCi/m2. It is also possible to escalate dose based on tracer-projected marrow, blood or whole body radiation dose. We describe our results in performing a dose-escalation trial in patients with non-Hodgkin lymphoma based on escalating administered whole-body radiation dose. The mCi dose administered was based on a patient-individualized tracer projected whole-body dose. 25 patients were entered on the study. RIT with 131 I anti-B-1 was administered to 19 patients. The administered dose was prescribed based on the projected whole body dose, determined from patient-individualized tracer studies performed prior to RIT. Whole body dose estimates were based on the assumption that the patient was an ellipsoid, with 131 antibody kinetics determined using a whole-body probe device acquiring daily conjugate views of 1 minute duration/view. Dose escalation levels proceeded with 10 cGy increments from 25 cGy whole-body and continues, now at 75 cGy. The correlation among potential methods of dose escalation and toxicity was assessed. Whole body radiation dose by probe was strongly correlated with the blood radiation dose determined from sequential blood sampling during tracer studies (r=.87). Blood radiation dose was very weakly correlated with mCi dose (r=.4) and mCi/kg (r=.45). Whole body radiation dose appeared less well-correlated with injected dose in mCi (r=.6), or mCi/kg (r=.64). Toxicity has been infrequent in these patients, but appears related to increasing whole body dose. Non-invasive determination of whole-body radiation dose by gamma probe represents a non-invasive method of estimating blood radiation dose, and thus of estimating bone marrow radiation dose.

• OSTI ID: 198092
• Report Number(s): CONF-940605--
• Journal Information: Journal of Nuclear Medicine, Journal Name: Journal of Nuclear Medicine Journal Issue: Suppl.5 Vol. 35; ISSN JNMEAQ; ISSN 0161-5505
• Country of Publication: United States
• Language: English

Related Subjects

55 BIOLOGY AND MEDICINE
BASIC STUDIES
56 BIOLOGY AND MEDICINE
APPLIED STUDIES
BLOOD
BODY
BONE MARROW
IODINE 131
LYMPHOMAS
PATIENTS
RADIATION DOSES
RADIOIMMUNOTHERAPY
TOXICITY