[Improving local control in patients with aggressive fibromatosis by combined surgery and radiotherapy]

[Aggressive Fibromatosis: Retrospective Analysis of 110 Patients]

Aggressive fibromatosis, histologically classified as benign due to the absence of metastasis, is characterised by locally invasive and destructive growth with high recurrence rates after resection. For this reason, prognostic recurrence factors, in particular the extent of resection, are much debated, and treatment decisions seem challenging for interdisciplinary tumour conferences. Between the years 2000 and 2020, 110 patients with aggressive fibromatosis of the extremities or trunk received surgical treatment at BG University Hospital Bergmannsheil (Bochum, Germany). Univariate analyses were performed to detect any potential prognosis factors. The median follow-up time was 5.9 years. A total of 57 (51.8%) of these patients developed recurrence during this period. The 5-year recurrence-free survival was 52.9% (95% CI: 42.4-62.3) in the entire cohort. In R0-resected patients, the 5-year recurrence-free survival (RFS) was significantly better (p<0.001) at 69.2% compared with patients with R1 or R2-resected tumours (32.6%). Beyond that, no other significant influencing factors were identified. The results of this study indicate that R0 resection or R0 resectability were associated with a significantly better local control. The therapeutic recommendation for resection should be made individually by an interdisciplinary tumour board in due consideration of tumour progression, possible therapeutic alternatives, and foreseeable functional impairment.

Diagnosis and treatment of extraabdominal desmoid fibromatosis

INTRODUCTION

The desmoid fibromatosis is a very rare connective tissue disease which is recognized as semimalignant. The aim of this work is to review the relevant literature and to analyze the management of our patient collective.

MATERIAL AND METHOD

Surgery was performed on 7 patients with extraabdominal desmoid fibromatosis between August 1998 and May 2007. MRI examination as well as biopsy was carried out in all cases. All patients were operated on; the mean follow up was 4 years (1-7). Upon follow up, every patient has undergone clinical and MRI examination.

RESULTS

The results show that we have achieved R0 resection in 4 cases and R1 in two cases and Rx in one case. In 4 patients, no recurrence was observed after the single surgery performed in our hospital. In 2 patients a single revision surgery was performed in each case and yielded no further recurrence. In only one case, multiple surgeries (one primary and two revision surgeries) were necessary, after which no recurrence was reported.

CONCLUSION

The early diagnosis of the disease is of utmost importance to the success of the outcome. MRI examination and biopsy are mandatory. Surgery is the therapy of choice. The recurrence rate is high and is linked to the difficulty of recognition of the exact infiltrative extent of the tumour. This necessitates a close follow-up.

CTNNB1 mutation analysis is a useful tool for the diagnosis of desmoid tumors: a study of 260 desmoid tumors and 191 potential morphologic mimics

Desmoid tumors are benign monoclonal fibroblastic or myofibroblastic neoplasms, characterized by local invasiveness and high rates of recurrence. Desmoid tumors must be distinguished from benign fibroblastic and myofibroblastic lesions, as well as from low-grade sarcoma, which can appear histologically similar to desmoid tumors. This differential diagnosis can be very difficult, especially when diagnosis is based on a core needle biopsy. On the molecular level, most sporadic desmoid tumors are associated with mutations of the β-catenin gene (CTNNB1). A minority of desmoid tumors are associated with Gardner syndrome and mutations of the familial adenomatous polyposis gene. We identified the common CTNNB1 mutations associated with sporadic desmoid tumors by direct sequencing: in (i) 260 cases of typical desmoid tumors; and (ii) in 191 cases of spindle cell lesions, which can morphologically 'mimic' desmoid tumors. Formalin-fixed paraffin-embedded tissues were obtained via core needle biopsy (n=150) or open biopsy/surgical excision (n=301). Only 16 cases (4%) were not analyzable (Bouin's fixed tissue). CTNNB1 mutations were observed in 223 of 254 (88%) of sporadic desmoid tumors. No CTNNB1 mutations were detected in all other lesions (n=175) studied. CTNNB1 sequencing can be easily and reliably done using tissues obtained via core needle biopsy. Detection of CTNNB1 mutations in formalin-fixed paraffin-embedded tissues among spindle cell lesions is proposed as a specific diagnostic tool for the diagnosis of desmoid tumors. This result has significant implications for patient care and management.

Prognostic Factors Influencing Progression-Free Survival Determined From a Series of Sporadic Desmoid Tumors: A Wait-and-See Policy According to Tumor Presentation

Purpose

Desmoid tumors are mesenchymal fibroblastic/myofibroblastic proliferations with locoregional aggressiveness and high ability to recur after initial treatment. We present the results of the largest series of sporadic desmoid tumors ever published to determine the prognostic factors of these rare tumors.

Patients and Methods

Four hundred twenty-six patients with a desmoid tumor at diagnosis were included, and the following parameters were studied: age, sex, delay between first symptoms and diagnosis, tumor size, tumor site, previous history of surgery or trauma in the area of the primary tumor, surgical margins, and context of abdominal wall desmoids in women of child-bearing age during or shortly after pregnancy. We performed univariate and multivariate analysis for progression-free survival (PFS).

Results

In univariate analysis, age, tumor size, tumor site, and surgical margins (R2 v R0/R1) had a significant impact on PFS. PFS curves were not significantly different for microscopic assessment of surgical resection quality (R0 v R1). In multivariate analysis, age, tumor size, and tumor site had independent values. Three prognostic groups for PFS were defined on the basis of the number of independent unfavorable prognostic factors (0 or 1, 2, and 3).

Conclusion

This study clearly demonstrates that there are different prognostic subgroups of desmoid tumors that could benefit from different therapeutic strategies, including a wait-and-see policy.

Molecular characterization by array comparative genomic hybridization and DNA sequencing of 194 desmoid tumors

Desmoid tumors are fibroblastic/myofibroblastic proliferations. Previous studies reported that CTNNB1 mutations were detected in 84% and that mutations of the APC gene were found in several cases of sporadic desmoid tumors lacking CTNNB1 mutations. Forty tumors were analyzed by comparative genomic hybridization (CGH). Karyotype and fluorescence in situ hybridization revealed a nonrandom occurrence of trisomy 8 associated with an increased risk of recurrence. We report the first molecular characterization including a large series of patients. We performed array CGH on frozen samples of 194 tumors, and we screened for APC mutations in patients without CNNTB1 mutation. A high frequency of genomically normal tumors was observed. Four relevant and recurrent alterations (loss of 6q, loss of 5q, gain of 20q, and gain of Chromosome 8) were found in 40 out of 46 tumors with chromosomal changes. Gain of Chromosomes 8 and 20 was not associated with an increased risk of recurrence. Cases with loss of 5q had a minimal common region in 5q22.5 including the APC locus. Alterations of APC, including loss of the entire locus, and CTNNB1 mutation could explain the tumorigenesis in 89% of sporadic desmoids tumors and desmoids tumors occurring in the context of Gardner's syndrome. A better understanding of the pathogenetic pathways in the initiation and progression of desmoid tumors requires studies of 8q and 20q gains, as well as of 6q and 5q losses, and study of the Wnt/beta-catenin pathway.

Radiation therapy for aggressive fibromatosis (desmoid tumors): results of a national Patterns of Care Study

PURPOSE

After a general Patterns of Care Study (PCS) the German Cooperative Group on Radiotherapy for Benign Diseases (GCG-BD) initiated a multicenter cohort study to analyze the radiation therapy practice for aggressive fibromatosis.

METHODS AND MATERIALS

In 2002 a PCS was conducted in all German radiotherapy (RT) institutions by mailing a standardized structured questionnaire, to assess patients accrual, number, pretreatment, treatment indications, RT, and target volume concepts for irradiation in aggressive fibromatosis. In addition, the treatment outcome of individual patients was evaluated. The PCS was structured and analyzed according to the model for quality assessment by Donabedian in three major components: structure, process, and outcome evaluation.

RESULTS

A total of 101 institutions returned the questionnaire: 52.7% reported satisfactory clinical data and experience for inclusion in this analysis. A total accrual rate of 278 patients per year was reported with median number of 2 cases (1-7 cases) per institution. Satisfactory data for a long-term clinical evaluation was reported for 345 patients from 19 different institutions. The applied total doses ranged between 36 and 65 Gy (median, 60 Gy). The local control rate was 81.4% in primary RT for unresectable tumors and 79.6% in postoperative RT. No acute or late radiation toxicities > Grade 2 (RTOG) were observed. No clear dose-response relationship could be established, but there was a tendency toward a lower local control rate in patients with a higher number of operative procedures before RT and patients treated for recurrent aggressive fibromatosis.

CONCLUSIONS

This study comprises the largest database of cases reported for RT in aggressive fibromatosis. Radiotherapy provides a high local control rate in the postoperative setting and in unresectable tumors. This PCS may serve as a starting point for a national or international prospective multicenter study or registry, or both.