[How are tumor markers used in diagnosis and in after-care of gastrointestinal cancers? Results of a nation-wide German survey].

To obtain appropriate information about the present use of tumor-associated antigens (TAA) in diagnosis and follow-up of gastrointestinal carcinomas, an inquiry into 102 German university and non-university hospitals was performed. 97 answers to ten standardized questions were available for evaluation. TAA are generally used in gastrointestinal carcinomas by 98.5% and 92.6% of internists (i) and surgeons (s), respectively. Preoperatively, serum concentrations of TAA are determined in 63.9% (i) and 84% (s) of gastric carcinomas. The corresponding rates in colorectal carcinomas are 93.8% and 92.6%. TAA are a routine part of postoperative care in 68.8% (i) and 76% (s) of gastric and in 100% (i) and 96.2% (s) of colorectal cancers. Interest is almost exclusively focused on CEA and CA 19-9. Other tumor associated antigens are rarely investigated in these diseases. Increasing serum concentrations of TAA induce intensive diagnostic procedures in 82.4% and 95.7% of internists and surgeons. However, an indication for a second-look operation solely based on increasing TAA concentrations is only seen by 30.6% of internists and 37% of surgeons. In gastric cancer the course of TAA concentrations is used for determining the effects of chemo- or radiotherapy in 36.4% (i) and 71.4% (s). The corresponding rates for colorectal carcinomas vary between 66.6% (i) and 80% (s). The results of this nation-wide inquiry confirm the wide use of CEA and CA 19-9 in gastrointestinal carcinomas. There are obvious differences with respect to diagnostic or therapeutic consequences based on postoperatively increasing serum levels of TAA.(ABSTRACT TRUNCATED AT 250 WORDS)