Strahlentherapie und Onkologie Original Article Recurrent Rectal Cancer within the Pelvis A Multicenter Analysis of 123 Patients and Recommendations for Adjuvant Radiotherapy Stefan Höcht 1 , Riad Hammad 1 , Hans-Joachim Thiel 2 , Thomas Wiegel 1 , Alessandra Siegmann 1 , Jochen Willner 3 , Peter Wust 4 , Thomas Herrmann 5 , Michael Eble 6 , Michael Flentje 3 , Detlef Carstens 7 , Dirk Bottke 1 , Patrick Neumann 8 , Wolfgang Hinkelbein 1 Background and Purpose: Recommendations for radiation ports in adjuvant radiation therapy for rectal cancer are mainly based on analysis of recurrence patterns. To evaluate whether changes in surgical technique have influenced this pattern of recurrence, a multicenter retrospective analysis was carried out on a patient population treated recently. Patients and Methods: 123 patients were evaluated with the help of a CT-based self-developed 3-D data file system and an ex- tensive questionnaire. Major inclusion criteria (one sufficient) for eligibility were: histological confirmation, clear bone destruc- tion, and a positive PET scan, or at least three minor criteria: progressive soft tissue mass, invasion of adjacent organs on follow- up CT or MRI, rising tumor markers, and typical appearance in cross-sectional imaging. Clinical or serologic signs of inflammation were exclusion criteria. Results: Initially, 54% of the evaluated patients were N0; in the remainder, N1 and N2 were distributed evenly. Initial T-catego- ry was T1 in 2%, T2 in 24%, T3 in 60%, and T4 in 13%, the male-to-female ratio was 2 : 1. Recurrent tumors were mainly situat- ed in the posterior part of the bony pelvis as displayed in the figures. When abdominoperineal resection was compared to low an- terior resection as primary operation, there was a significant difference in extension of recurrent tumors in the inferior parts of the pelvis (p < 0.025 in all statistical tests applied), whereas no significant difference was found in the superior parts of the pelvis. Conclusion: Based on these results, a modest field size reduction in adjuvant radiotherapy for rectal cancer seems feasible, of- fering the perspective of a reduction in acute and late side effects. Key Words: Rectal cancer · Pelvic recurrence · Adjuvant therapy · Radiation ports Strahlenther Onkol 2004;180:15–20 DOI 10.1007/s00066-004-1130-8 Pelvine Rektumkarzinomrezidive. Eine Multicenteranalyse von 123 Patienten und Empfehlungen für die Feldwahl bei der adjuvanten Bestrahlung Hintergrund und Ziel: Die Empfehlungen zur Wahl der Strahlenfelder bei der adjuvanten Therapie des Rektumkarzinoms basieren hauptsächlich auf Auswertungen der Rezidivverteilungsmuster. Um zu untersuchen, ob aktuelle operative Techniken Einfluss auf dieses Rezidivmuster haben, wurde eine retrospektive Multicenteranalyse an einem aktuell behandelten Krankengut unternommen. Patienten und Methodik: 123 Patienten wurden anhand einer CT-basierten selbst entwickelten 3-D-Datenbank und eines um- fangreichen Fragebogens ausgewertet. Die Diagnose wurde als gesichert angesehen, wenn ein Major-Kriterium (histologische Si- cherung, eindeutige Osteodestruktion oder ein positiver PET-Scan) oder mindestens drei Minor-Kriterien (progredienter Weichteil- tumor in Verlaufs-CTs oder MRTs, Anstieg der Tumormarker, Invasion bzw. Infiltration in Nachbarorgane und typisches Aussehen in der Schnittbilddiagnostik) vorlagen. Patienten mit klinischen oder serologischen Entzündungszeichen wurden ausgeschlossen. Ergebnisse: Initial fand sich bei 54% der ausgewerteten Patienten eine N0-Situation; bei den restlichen Patienten waren N1 and N2 gleich häufig. Initiale T-Kategorie war T1 in 2%, T2 in 24%, T3 in 60% und T4 in 13%; die Geschlechtsverteilung (männlich Received: December 2, 2002; accepted: May 6, 2003 1 Department of Radiation Oncology and Radiotherapy, Charité Campus Benjamin Franklin, Berlin, Germany, 2 Department of Radiation Oncology and Radiotherapy, Bamberg Hospital, Bamberg, Germany, 3 Department of Radiation Oncology and Radiotherapy, University Hospital Würzburg, Germany, 4 Department of Radiation Oncology and Radiotherapy, Charité Campus Virchow-Klinikum, Berlin, Germany, 5 Department of Radiation Oncology and Radiotherapy, University Hospital Carl Gustav Carus, Technical University of Dresden, Germany, 6 Department of Radiation Oncology and Radiotherapy, University Hospital, RWTH Aachen, Germany, 7 Department of Radiation Oncology and Radiotherapy, General Hospital St. Georg, Hamburg, Germany, 8 Institute for Medical Informatics, Biometry, and Epidemiology, University Hospital Benjamin Franklin, Free University of Berlin, Germany. 15 Strahlenther Onkol 2004 · No. 1 © Urban & Vogel