Radiotherapy and Oncology 34 (1995) 17-22 Aggressive fibromatosis: optimisation of local management with a retrospective failure analysis C.N. Catton*a, B. O’Sullivan”, R. Bellb, B. Cummings”, V. Fornasierc, T. Panzarellad “The University of Toronto and Departmenr of Radiation Oncology, The Princess Margaret Hospital. 500 Sherbourne St, Toronto, ON, Canada M4N lK9 bDepartment of Surgical Oncology, The Princess Margaret Hospital. Toronto, Canada cDepartmeni of Pathology, The Wellesley Hospital. Toronto, Canada ‘Department of Biostatistics. The Princess Margaret Hospital, Toronto, Canada Received 12 September 1994; revision received 21 October 1994;accepted 3 November 1994 Abstract The records of 40 consecutive patients treated at the Princess Margaret Hospital (PMH) between 1979and 1988for aggressive fibromatosis were reviewed. The median follow-up was 86 months (range 21-167 months). All surgery was performed at the referr- ing hospitals. Thirty-six underwent an attempt at excision, four were biopsied. Thirty-one had no overt disease after surgery and 26 of these received adjuvant irradiation. Eight were treated with radiotherapy alone, and another was treated with azathioprine and prednisone. Twenty-four (60%) presentedwith recurrent disease. The overall relapsefree rate was 63% at 5 and 10years. Com- bined surgery and irradiation had a higher relapse rate than irradiation alone (46% vs. 25%) and a high proportion of failures in the combined group were marginal failures (36%). Relapses following surgery alone were l/5 (20%), and chemotherapy O/l. Tumour sizegreater than 8 cm predicted for relapse@ = 0.002),but tumour site, status of surgical margins, and presence or absence of a history of relapsewere not statistically significant. Twelve with subsequent treatment failure underwent successful salvagesur- gery, and 37/40(92%) were disease free at last follow-up. A functional assessment (modified Johnstone scale)revealed 1 l/24 patients (46%) with poor functional outcomes (grade 2 or less) after all treatment compared with 6/24 (25%) at referral. Ten of 11 (91%) with grade of 2 or less had a history of recurrence, and 4/S amputations were for treatment of a painful recurrence. Treatment planning in this study was hampered by inadequate information on tumour location since few patients had clinically apparent disease when Seen by the radiation oncologist (only 35% of cases) and fewer had preoperative cross-sectional imaging available (12% of cases). Relapse was also associatedwith a poor functional outcome. Attaining high rates of local control with good func- tional outcomes requires a thorough pretreatment assessment of local diseaseand optimal selection, integration and delivery of the treatment modalities available. Combined surgery and irradiation should be considered and planned jointly for those patients at risk for relapse or with diseasein sites where relapse would subsequently compromise function. Keywords: Aggressive tibromatosis; Treatment; Radiation therapy; Functional outcome 1. Introduction Aggressive fibromatosis is an uncommon, benign soft tissueneoplasm. It is a cellular tumour composedof well differentiated libroblasts, and affects femalesmore com- monly than males. It does not metastasize, is non- encapsulatedand has a tendency to infiltrate widely be- tween muscle fibres and along fascial planes and neurovascular bundles [ 14,15,27]. This behaviour may * Corresponding author. not only result in significant injury to adjacent normal tissues and structures but also increases the risk of treat- ment failure if the full extent of the diseaseis not ap- preciated prior to therapy. Involvement of nerves and vessels vital to normal function may also compromise the performance of an effective operation, or if radiosensitive structures like the spinal cord are adja- cent, can complicate the effective delivery of curative radiotherapy. Treatment decision making is complicated by the variable natural history of the disease,since in certain 0167-8140/95/$09.50 0 1995 Elsevier Science Ireland Ltd. All rights reserved SSDI 0167-8140(94)01483-J