Differences in biodistribution of indium-111-and iodine-131-labeled B72. 3 monoclonal antibodies in patients with colorectal cancer

Journal Article · Wed Mar 01 00:00:00 EST 1989 · J. Nucl. Med.; (United States)

OSTI ID:5601984

Yokoyama, K; Carrasquillo, J A; Chang, A E; Colcher, D; Roselli, M; Sugarbaker, P; Sindelar, W; Reynolds, J C; Perentesis, P; Gansow, O A

We have compared the biodistributions of (/sup 131/I)B72.3 and /sup 111/In-SCN-Bz-DTPA B72.3 monoclonal antibody (MoAb) in patients with metastatic colon cancers. B72.3 is an IgG1 that recognizes a mucin-like colon cancer associated antigen. Eight patients were infused with 3-5 mCi and 0.36-20 mg of /sup 111/In-labeled B72.3 prepared with a bifunctional chelate, isothiocyanatobenzyl-DTPA (SCN-Bz-DTPA). The biodistribution was compared with that of 13 patients previously studied as part of a separate trial, with 1-10 mCi and 0.16-1.35 mg of (/sup 131/I)B72.3. The Beta T1/2 in serum was 63 +/- 5 hr for 111In-SCN-Bz-DTPA B72.3 and 52 +/- 10 hr for (/sup 131/I)B72.3. Whole-body retention of the /sup 111/In (T1/2 = 11.8 days) was significantly longer than for (/sup 131/I)B72.3 (T1/2 = 3.3 days), p less than 0.000001. The /sup 131/I was excreted primarily through the urine. Urinary excretion of /sup 111/In was low and gamma camera images confirmed that some /sup 111/In was excreted in the bowel. Tumor localization was seen in one of seven evaluable patients receiving /sup 111/In-SCN-Bz-DTPA B72.3. Gamma camera images showed that the liver concentrates /sup 111/In but not /sup 131/I. We conclude that /sup 111/In-SCN-Bz-DTPA B72.3 is metabolized in a different manner from the iodinated B72.3. The high concentration and prolonged retention of /sup 111/In by the liver interferes with tumor imaging of metastases.

• Research Organization: Warren G. Magnuson Clinical Center, Bethesda, MD (USA)
• OSTI ID: 5601984
• Journal Information: J. Nucl. Med.; (United States), Vol. 30:3
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
LARGE INTESTINE
NEOPLASMS
MONOCLONAL ANTIBODIES
TISSUE DISTRIBUTION
DIAGNOSIS
RECTUM
COMPARATIVE EVALUATIONS
DTPA
IODINE 131
LIVER
METASTASES
PATIENTS
AMINO ACIDS
ANTIBODIES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BODY
CARBOXYLIC ACIDS
CHELATING AGENTS
DAYS LIVING RADIOISOTOPES
DIGESTIVE SYSTEM
DISEASES
DISTRIBUTION
DRUGS
GASTROINTESTINAL TRACT
GLANDS
INTERMEDIATE MASS NUCLEI
INTESTINES
IODINE ISOTOPES
ISOTOPES
NUCLEI
ODD-EVEN NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANS
RADIOISOTOPES
RADIOPROTECTIVE SUBSTANCES
550601* - Medicine- Unsealed Radionuclides in Diagnostics