Radioimmunoscintigraphy of colorectal carcinoma using technetium-99m-labeled, totally human monoclonal antibody 88BV59H21-2.

Radioimmunoscintigraphy (RIS) using human monoclonal antibodies offers the important clinical advantage of repeated imaging over murine monoclonal antibodies by eliminating the cross-species antibody response. This article reports a Phase I-II clinical trial with Tc-99m-labeled, totally human monoclonal antibody 88BV59H21-2 in patients with colorectal carcinoma. The study population consisted of 34 patients with colorectal cancer (20 men and 14 women; age range, 44-81 years). Patients were administered 5-10 mg antibody labeled with 21-41 mCi Tc-99m by the i.v. route and imaged at 3-10 and 16-24 h after infusion using planar and single-photon emission computed tomographic (CT) techniques. Pathological confirmation was obtained in 25 patients who underwent surgery. Human antihuman antibody (HAHA) titers were checked prior to and 1 and 3 months after the infusion. RIS with Tc-99m-labeled 88BV59H21-2 revealed a better detection rate in the abdomen-pelvis region compared with axial CT. The combined use of both modalities increased the sensitivity in both the liver and abdomen-pelvis regions. Ten patients developed mild adverse reactions (chills and fever). No HAHA response was detected in this series. Tc-99m-labeled human monoclonal antibody 88BV59H21-2 RIS shows promise as a useful diagnostic modality in patients with colorectal cancer. RIS alone or in combination with CT is more sensitive than CT in detecting tumor within the abdomen and pelvis. Repeated RIS studies may be possible, due to the lack of a HAHA response.

Preoperative scintigraphy and operative probe scintimetry of colorectal carcinoma using technetium-99m-88BV59.

UNLABELLED: We report a pilot study of radioimmunoscintigraphy (RIS) and operative gamma probe scintimetry (OPS) using a 99mTc-labeled anti-cytokeratin human monoclonal antibody (MAb) (99mTc-88BV59) in patients with newly diagnosed, recurrent or metastatic colorectal cancer. METHODS: Twelve presurgical patients with biopsy- or contrast radiographic-proven colorectal cancer or recurrent colorectal carcinoma were studied. After chest roentgenography and abdominopelvic CT, 99mTc-88BV59 was administered intravenously, planar and SPECT external imaging was performed 3 to 6 hr after injection and planar imaging was performed 18 to 24 hr after injection. Surgery was performed immediately after late planar imaging. OPS of a standardized list of sites to document background radiation activity and of tumor sites, resection margins and tumor beds was performed. RESULTS: The patients had 23 histologically proven tumor sites. Overall sensitivity for CT, planar RIS, SPECT, surgery and OPS was 43%, 61%, 78%, 96% and 91%, respectively. SPECT was superior to CT for imaging extrahepatic abdominal and pelvic disease. OPS detected all liver and extrahepatic abdominal tumor sites and correctly predicted histological tumor-free margins and tumor beds in all cases. OPS did not identify tumor deposits that the surgeon could neither see nor feel. No patient demonstrated human anti-human immune responsiveness 1 and 3 mo after 99mTc-88BV59 infusion. CONCLUSION: Technetium-99m-88BV59 is a safe, effective radioimmunoconjugate for colorectal cancer imaging, with superior sensitivity as compared to CT.

Radioimmunodetection of colorectal carcinoma using technetium-99m-labeled Fab' fragments of the IMMU-4 anti-carcinoembryonic antigen monoclonal antibody.

BACKGROUND: Radioimmunodetection of cancer using monoclonal antibody fragments offers certain potential advantages over that with whole monoclonal antibodies, including the ability to image early (i.e., to provide images at an early time after injection of the radioantibody) while minimizing the incidence of human anti-mouse antibody response. This paper reports a prospective trial comparing radioimmunodetection with IMMU-4 (a murine anti-CEA monoclonal antibody) 99mTc-labeled Fab' fragments to conventional imaging in 35 colorectal cancer patients. METHODS: All patients were investigated by conventional diagnostic methods (CDM) within 4 weeks of radioimmunodetection. Surgical corroboration of findings was obtained in 26 patients (15 with evidence of disease on CDM [CDM+] and 11 with abnormal serum CEA [CDM-] as the only evidence for recurrence). After 1 mg IMMU-4 99mTc-Fab' was injected (19.3 mCi on average), patients underwent planar/SPECT radioimmunodetection 2-5 hours later and planar radioimmunodetection 18-24 hours later. Three patients underwent a second radioimmunodetection study 16, 20 and 23 months after the first. RESULTS: Radioimmunodetection was superior to CDM, accurately predicting disease distribution in six nonsurgical and ten CDM+ surgical patients, and was complementary to computed tomography in two nonsurgical and two CDM+ surgical patients. Radioimmunodetection would have directed or changed management decisions in 6 of the 15 (40%) CDM+ surgical patients. Radioimmunodetection correctly identified all recurrent tumor in 8 of 11 CDM- surgical patients and was negative in one patient with cirrhosis and no recurrence, representing a potential clinical benefit of 82%. Analyzed on a regional basis, radioimmunodetection was found to be superior to CDM in extrahepatic abdomen and pelvis imaging and was complementary to (although not as accurate as) CDM in the liver. Human anti-mouse antibody did not develop in any of the patients, including three who were injected twice. CONCLUSIONS: IMMU-4 99mTc-Fab' radioimmunodetection shows promise as a clinically useful diagnostic tool in patients with colorectal cancer, detecting disease often missed by conventional imaging. IMMU-4 99mTc-Fab' may prove useful for serial radioimmunodetection studies, because human anti-mouse antibody response does not appear to be a problem with this radioimmunoconjugate. It also has the advantage of permitting same-day imaging.

[The importance of Scotochromogenous mycobacteria in the urine]. / La importancia de las micobacterias escotocromógenas en la orina. Análisis de 155 casos

In order to find the significance of the presence of Scotochromogenous Mycobacteria in the urine, 155 cases with this finding and without other Mycobacteria were analyzed. Most had urinary symptoms (91.6%), abnormal urine analysis (62.5%), negative urine culture (71.7%), and changes in intravenous pyelograms (89.5%). Clinical and laboratory improvement was noticed in 70% of those who received antituberculous drugs and in 30% of those who did not receive them (P less than 0.01). All of the foregoing characteristics were present in each 23 patients with repeated isolations of Scotochromogens in the urine, and could be cases of urinary-tract disease due to Scotochromogens. In other patients this Mycobacteria could coexist with M. tuberculosis, or be a contaminant, although Scotochromogens were not found in the urine of 100 control subjects, a significant difference to these patients (P less than 0.0001).