HIGHLY FLEXIBLE SELF-EXPANDING METAL MESH STENTS - INNOVATIVE THERAPYFOR PALLIATION OF MALIGNANT DYSPHAGIA

Metal mesh stents are a new way in the treatment of malignant stenoses . Between 11/91 and 12/93 in 79 patients with malignant stenoses of th e esophagus and the esophago-gastric junction 96 highly elastic, knitt ed, selfexpanding nitinol stents (Ultraflex(R), Boston Scientific) wer e implanted. Most of the tumors being problematic, preoperated or prer adiated, in 78 of 96 implantations endoscopic pretreatment (Laser, Arg on Plasma Coagulation (APC), dilatation) - mostly in the same session - was necessary. Follow up time was 21 (2-108) weeks. In this pilot st udy 3,5 (1-27) controlendoscopies with 2,5 (1-10) endoscopic intervent ions were performed. 90 of 96 implantations were primarily successful and led to a functional success in 73 of 79 patients. The ability to s wallow improved significantly, the score of dysphagia improved from 3, 5 to 1,0 (p < 0,001). There were no relevant complications and no sten t-related mortality. All stents could be kept patent during the follow up period using the new developed Argon-plasma-coagulation (APC) to t reat the ingrowth of granulation tissue or tumor, which was observed d uring follow up in 72 of 93 implantations. Tumor ingrowth represents t he main problem of the method and demands endoscopic posttreatment (AP C) in cases with relevant re-obstruction. Impairment of the stent lume n by tumor ingrowth (granulation tissue plays no role) would have been observed in about 60% of the patients without such a treatment. These new highly flexible selfexpanding stents are a favourable - but still expensive - alternative to established methods and offer remarkable a dvantages: easy handling and implantation, impressing long term functi onal improvement, good tolerance by and remarkable good quality of lif e for the patients and the possibility to manipulate or remove the ste nts endoscopically. Especially in problematic cases (high cervical pos ition, extreme length, kinking, preradiation) such a stent may offer t he only effective therapy. The problem of tissue ingrowth has to be so lved by further developments, especially in respect to covering. The p rototypes of coated stents available, however, seem to be not yet sati sfactory. Further innovations may make the principle of stenting suita ble for extended indications. Our latest results (until 6/95 a total o f 132 patients was treated with 162 stents) with new prototypes of hig hly flexible Nitinol stents confirm the impression that these stents r epresent a valuable alternative in palliative therapy.