Clinical value of immunoscintigraphy in colorectal carcinoma patients: a prospective study.

Fifty-seven patients with suspected CEA-producing tumors were studied prospectively by radioimmunoscintigraphy (RIS) using a 123I-labeled anti-CEA monoclonal antibody (MAb) (essentially the F(ab')2 or Fab fragments) and emission computed tomography (ECT). Results of RIS were compared to those of a comprehensive diagnostic study. Final diagnosis was based on surgery, biopsy and autopsy (n = 39) or follow-up findings (n = 18). Three groups of patients were defined: Group A with suspected primary tumors (n = 11), Group B with probable (n = 19) and Group C with questionable (n = 27) tumor relapse. Eighty-eight per cent, 93% and 71% of the anatomic regions studied were correctly identified as being involved, and 97%, 97%, and 87% as being free from tumor in Groups A, B, and C, respectively. In the 27 patients from Group C with no definite diagnosis of relapse, and in whom diagnosis was most difficult, 38 tumor sites were involved. Of these, 21 were detected by both prospective RIS and repeated comprehensive study, six by RIS only and seven by conventional methods only. Four sites remained undetected by both approaches. Ten of the 21 lesions were detected by RIS more than 1 mo earlier than by any other method. Among the seven tumor sites detected by other diagnostic modalities only, three were identified at the time of RIS and four became positive more than 6 mo later. Overall diagnosis was entirely correct in 30, partially correct in 16 and incorrect in six patients studied. RIS with ECT and 123I-labeled anti-CEA MAb allows early detection of recurrence or metastasis of colorectal cancer. It thus contributes to reduced delay between diagnosis and treatment.

[Totally implantable catheters. Experience at the University Hospital Center Vaudois from March 1984 to December 1987]. / Cathéters totalement implantables. L'expérience du Centre hospitalier universitaire vaudois de mars 1984 à décembre 1987.

With cancer patients, the venous access remains a major problem. It causes phlebitis, venous sclerosis, skin necrosis and sepsis. Its maintenance implies careful nursing and a great dependence for the patient. Arterio-venous fistulas have been abandoned and replaced by Hickman-type subcutaneous indwelling catheters. These have a complication rate, mainly infectious, of about 0.4/100 days. The development of totally implanted catheters diminishes even more this rate and improves the patient's comfort. In this article we report the experience gained from 100 cancer patients equipped with 107 catheters. 31 complications occurred over a total time of 15,421 days, this averages a rate of 0.2 complications/100 days. The respectively rate of thrombosis and infections are of 0.02/100 days each. In 61% of the cases the whole system was functional after management of the complication. This results confirm the excellent tolerance of the system, its minimal rate of complication and its great possibility of reutilization.

Detection of colorectal carcinoma by emission-computerized tomography after injection of 123I-labeled Fab or F(ab')2 fragments from monoclonal anti-carcinoembryonic antigen antibodies.

This clinical study was based on experimental results obtained in nude mice grafted with human colon carcinoma, showing that injected 131I-labeled F(ab')2 and Fab fragments from high affinity anti-carcinoembryonic antigen (CEA) monoclonal antibodies (MAb) gave markedly higher ratios of tumor to normal tissue localization than intact MAb. 31 patients with known colorectal carcinoma, including 10 primary tumors, 13 local tumor recurrences, and 21 metastatic involvements, were injected with 123I-labeled F(ab')2 (n = 14) or Fab (n = 17) fragments from MAb anti-CEA. The patients were examined by emission-computerized tomography (ECT) at 6, 24, and sometimes 48 h after injection using a rotating dual head scintillation camera. All 23 primary tumors and local recurrences except one were clearly visualized on at least two sections of different tomographic planes. Interestingly, nine of these patients had almost normal circulating CEA levels, and three of the visualized tumors weighed only 3-5 g. Among 19 known metastatic tumor involvements, 14 were correctly localized by ECT. Two additional liver and several bone metastases were discovered by immunoscintigraphy. Altogether, 86% of the tumor sites were detected, 82% with F(ab')2 and 89% with Fab fragments. The contrast of the tumor images obtained with Fab fragments suggests that this improved method of immunoscintigraphy has the potential to detect early tumor recurrences and thus to increase the survival of patients. The results of this retrospective study, however, should be confirmed in a prospective study before this method can be recommended for the routine diagnosis of cancer.

Resection of metastases to the alimentary tract from malignant melanoma.

Metastases to the celio-mesenteric organs from malignant melanoma are studied retrospectively in 22 autopsied cases and in seven surgically treated patients. Metastatic disease to one or more celio-mesenteric organs was found in 86.3% of postmortem examinations: the liver was the most frequently involved organ, followed by the pancreas, peritoneum, small bowel, biliary tract spleen, colon and stomach, in that order. Surgery only resulted in long-term asymptomatic survival in those patients with a long relapse-free interval and a single metastasis. It is concluded that, apart from cases with intestinal obstruction or massive GI bleeding, resection should be reserved for patients with a relapse-free interval of at least 15 months and with a single "alimentary" metastasis. It is suggested that diagnosis of systemic spread at the asymptomatic stage would improve prognosis of stage IV malignant melanoma.

[Indication for selective surgical excision of hepatic metastases]. / Indication sélective à l'exérèse chirurgicale des métastases hépatiques.

451 patients undergoing surgery for colorectal cancer showed synchronous hepatic metastases in 24.4% (110 cases). Survival of patients with hepatic metastases appears to depend on both the age of the patient and the site of metastatic deposit. A relatively good prognosis group with median survival of 14 months can be separated from the other patients with only 5 months survival. Survival of patients with hepatic metastases can thus be predicted and long-term survival (5 and 10 years) obtained by surgical excision of these metastases. Postoperative CEA determinations will also increase the rate of early surgery for hepatic metastases.