[Cytoreductive surgery and intraperitoneal hyperthermic-antiblastic therapy (HAPP) in peritoneal carcinomatosis]

Peritoneal carcinosis often occurs during the evolution of many neoplasias either abdominal or extra-abdominal. The free time survival of the patients affected by carcinosis is poor (about 6 months) as regards gastric and colorectal cancer. In the last ten-year period a combined surgical technique aiming at the total removal of parietal and visceral peritoneal lesions (peritonectomy) and at the perfusion of peritoneal cavity with chemo-drugs in hyper-thermia had developed. This method is based on the presence of the peritoneal-plasmatic barrier that holds back high molecular weight drugs, keeping from passing at the systemic circulation; in this way it is possible to use higher and more concentrate chemo-drug doses in a very limited area than in the systemic chemotherapy. The association between chemotherapy and hyperthermia produces a synergic effect: hyperthermia, infarct, makes chemo-drugs more effective and selective, improving their capability of penetration in tumoral masses; heat has furthermore an intrinsic anti-neoplastic action, being altered the reparation mechanisms of the tumoral cells. A WEB research on Medline site has been conducted choosing especially those articles referable at the 1999-2000 period. The selected articles have been briefly analysed in the "Clinical experience" section. Authors' experiences have been divided, as far as possible, on the basis of the tumors treatable with cytoreduction and HAPP: 1) Colon-rectal Cancer; 2) Pseudomyxoma peritonei/Appendicular Adenocarcinoma; 3) Gastric Cancer; 4) Ovarian Cancer; 5) Peritoneal Mesothelioma. The determinant variables in the analysis of the results are basically three: 1) Selection of the patients, 2) Characteristics of the surgical operation, 3) Characteristics of the HAPP. Colon-rectal carcinoma: the survival time of the recurrent disease, obtained by some authors like P.H. Sugarbaker, is surely remarkable (50% at 5 years in the patients where a complete cytoreduction was possible to perform), but the result obtained in patients affected by peritoneal carcinosis, subjected to this technique at the first clinical presentation (100% at 5 years) is much more interesting. For this type of neoplasia, it is important to underline that not all the authors report the same results, with a median survival time lower than that of the American author. Pseudomyxoma peritonei: about this rare neoplasia, the "golden standard" treatment consists on cytoreduction of all visceral and peritoneal macroscopical lesions, with a homogeneous distribution of the data obtained by most authors: median survival time included among 70% and 90% at 5 years. Gastric cancer: there is a considerable difference between the data of Japanese authors and others. In the treatment of peritoneal carcinosis the results are, on average, rather poor; better results have been obtained using this technique as an adjuvant presidium for the prevention of the onset of peritoneal carcinosis. Ovarian cancer: the results about the recurrent ovarian cancer are good; in the future, it will be useful to start a phase III study to render effective the use of this technique in the ovarian cancer at the beginning of its clinical story. Peritoneal mesothelioma: till now, a standardized alternative, approaching this neoplasia, does not exist; the results are encouraging, with good median and free time survival.