Not all abdominal masses after colorectal cancer surgery are malignant: intra-abdominal fibromatosis masquerading as recurrence.

AIM: Intra-abdominal fibromatosis is an unusual mesenchymal tumour that can be locally aggressive without any metastatic potential. Fibromatosis may simulate cancer recurrence on imaging surveillance for colorectal cancer follow-up. The optimal treatment of recurrent peritoneal malignancy is cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Confirmatory biopsy of lesions suspicious for colorectal cancer recurrence may not be feasible, thereby rendering surgery the safest option. Our aim was to determine the incidence of fibromatosis in a cohort of patients undergoing CRS and HIPEC for suspected colorectal cancer recurrence. METHODS: One hundred and seventy-one CRS and HIPEC cases were performed at our Peritoneal Malignancy Institute between February 2007 and October 2018 for colorectal peritoneal metastases and were included in a prospectively maintained database. RESULTS: A total of 49 (29%) of 171 cases were performed for primary colorectal cancer with peritoneal metastases, whereas 122 (71%) of 171 cases were performed for suspected colorectal cancer recurrence detected on surveillance imaging after primary colorectal cancer resection. On histological analysis of the resected specimen, five (4.1%) of 122 cases undergoing CRS and HIPEC for colorectal recurrence had fibromatosis. CONCLUSION: Fibromatosis can masquerade as colorectal cancer recurrence. In this series it occurred with an incidence of 4.1% among a cohort of patients undergoing CRS and HIPEC for probable recurrence. Surgical resection may be the only option to confirm the diagnosis and rule out malignancy.

The management of soft tissue tumours of the abdominal wall.

BACKGROUND: Soft tissue tumours of the abdominal wall account for approximately 10% of all soft tissue tumours. Tumours at this site comprise a heterogeneous group of pathologies with distinct clinical behaviours and responses to treatment. The management of these tumours has largely been extrapolated from studies of soft tissue tumours at other sites. This review aims to summarise the existing data relating to abdominal wall tumours and suggest principles for managing soft tissue tumours at this site. METHODS: Relevant articles were retrieved from a comprehensive literature search using the PubMed database. Key words included abdominal wall, soft tissue tumours, surgery, radiotherapy and chemotherapy. No restrictions on publication date were used. RESULTS: The most common pathologies presenting in the abdominal wall are desmoid tumours, soft-tissue sarcoma and dermatofibrosarcoma protuberans (DFSP). Desmoid tumours should be managed with an initial period of observation, with surgery reserved for progressive lesions. Surgery should be the primary treatment for soft-tissue sarcomas and DFSP, with radiotherapy reserved for large-high grade tumours and preferentially given pre-operatively. CONCLUSIONS: Abdominal wall tumours are rare and should be managed in centres with experience in the management of soft tissue tumours. Management should be tailored to the biological behaviour of specific pathologies.

Time trends in the incidence and treatment of extra-abdominal and abdominal aggressive fibromatosis: a population-based study.

BACKGROUND: Aggressive fibromatosis (AF) is a locally infiltrating soft-tissue tumor. In a population-based study in the Netherlands, we evaluated time trends for the incidence and treatment of AF. METHODS: In PALGA: Dutch Pathology Registry, all patients diagnosed between 1993 and 2013 as having extra-abdominal or abdominal wall aggressive fibromatosis were identified and available pathology data of the patients were evaluated. Epidemiological and treatment-related factors were analyzed with χ (2)and regression analysis. RESULTS: During the study period, 1134 patients were identified. The incidence increased from 2.10 to 5.36 per million people per year. Median age at the time of diagnosis increased annually by B 0.285 (P = 0.001). Female gender prevailed and increased over time [annual odds ratio (OR) 1.022; P = 0.058]. All anatomic localizations, but in particular truncal tumors, became more frequent. During the study period diagnostic histological biopsies were performed more often (annual OR 1.096; P < 0.001). The proportion of patients who underwent surgical treatment decreased (annual OR 0.928; P < 0.001). When resection was preceded by biopsy, 49.8 % of the patients had R0-resection versus 30.7 % in patients without biopsy (P < 0.001). CONCLUSIONS: In this population-based study, an increasing incidence of extra-abdominal and abdominal-wall aggressive fibromatosis was observed. The workup of patients improved and a trend towards a nonsurgical treatment policy was observed.

The outcome of extra-abdominal fibromatosis treated at a tertiary referral centre.

PURPOSE: To review the outcomes of patients with extra-abdominal fibromatosis treated at a tertiary referral centre. METHODS: A retrospective review of a series of 72 patients with fibromatosis treated at the Royal National Orthopaedic Hospital (RNOH) between 1980 and 2009, with a median follow up of 4 years (1-17 years). RESULTS: Forty patients were primary referrals, and 32 more had operations at the referring hospital. Five were treated non-operatively; 48 patients were treated by operation alone and 19 patients underwent surgery supplemented by adjuvant therapy. Recurrence was seen in 24 of the operation alone group and 10 in the operation and adjuvant therapy group. The rate of recurrence was lower with complete excision. However, complete excision was impossible in some cases because of extension into the chest or spinal canal, or involvement with the axial vessels and lumbosacral or brachial plexus. CONCLUSION: We suggest that operative excision should seek to preserve function and that supplementary adjuvant therapy may reduce the risk of recurrence, although excision margin appears to be the most important factor. The aggressive, infiltrative behaviour of deep fibromatoses and the associated genetic mutations identified, clearly distinguish them from the superficial fibromatoses and makes their treatment more difficult and dangerous, especially where vital structures are involved.

Risk factors predicting intra-abdominal desmoids in familial adenomatous polyposis: a single centre experience.

BACKGROUND: Desmoids are myofibroblastic proliferations occurring in 15% of patients with familial adenomatous polyposis (FAP), 70% being intra-abdominal desmoids (IAD). Since the morbidity and mortality due to desmoids is almost entirely attributable to IAD, we aimed to identify specifically risk factors predicting IAD development in FAP. METHODS: We undertook a retrospective review of our institutional database. Multivariate analysis was performed, and hazard ratios (HR) calculated for variables including female gender, 3' APC mutation, surgical intervention for FAP (colectomy with ileo-rectal anastomosis or restorative proctocolectomy), age at surgery and family history (FH) of desmoids. RESULTS: Of the 558 patients analysed, 49 (9%) developed IAD; 22 (4%) diagnosed intra-operatively and 27 (5%) developing over a median post-operative period of 34 (7-120) months. 75% of IAD had developed before age 40. A 3' APC mutation (HR 5.2, 95% CI 2.1-13.3, P = 0.001), positive FH (HR 2.5, 95% CI 1.4-4.6, P = 0.003) and female gender (HR 1.9, 95% CI 1.0-3.5, P = 0.04) were found to be predictive of IAD development. No significant difference in IAD risk was detected between the type of surgical intervention (P = 0.37) or age at surgery (P = 0.29). CONCLUSIONS: Our analysis confirms 3' APC mutation to be the most significant risk factor for IAD development. The independent association between positive FH and IAD risk suggests the existence of modifier genes, independent of the APC genotype-phenotype correlation. Few of these risk factors can be meaningfully modified. Delaying prophylactic surgery may be appropriate in female patients with a 3' APC mutation and attenuated polyposis.

Mesenteric desmoid tumors in Singapore familial adenomatous polyposis patients: clinical course and genetic profile in a predominantly Chinese population.

PURPOSE: This study examined the mutational profile of the adenomatous polyposis coli gene in relation to the development of desmoid tumors in familial adenomatous polyposis patients from a predominantly Chinese population. METHODS: This is a retrospective review of all patients with familial adenomatous polyposis coli from the Singapore Polyposis Registry. Identification of specific adenomatous polyposis coli gene mutation was performed and clinical course of associated desmoid disease obtained from case records and a computerized database. RESULTS: Two hundred five patients from 75 families afflicted with familial adenomatous polyposis coli were reviewed, with gene mutations identified in 107 patients. Of these, 23 (11.2 percent) developed desmoids. The male-to-female ratio was 1:1.3 and the ethnic distribution was Chinese (n=17) and Malay (n=6). Of the 92 patients with mutations 5' to codon 1444, 11 patients (12 percent) developed desmoids compared with 6 of 15 (40 percent) patients with adenomatous polyposis coli gene mutations 3' to codon 1444 (P<0.01). The clinical course of desmoid tumors can be divided into stable (n=11), variable (n=3), progressive (n=6), and aggressive growth (n=3). Only 3 (13 percent) patients with aggressive tumor growth required chemotherapy. There was no correlation between the site of mutation and the clinical progression of the desmoids. Seventy-four percent of these desmoids (17/23) developed at a mean interval of 2.98 years after restorative proctocolectomy, while only 30 percent (7/23) were diagnosed preoperatively or discovered during the initial surgery. The most common complications related to the mesenteric desmoids were intestinal obstruction (21.7 percent), ureteric obstruction (17.4 percent), and encasement of superior mesenteric vessels (13 percent). CONCLUSION: The clinical course of desmoids in an individual familial adenomatous polyposis patient remains unpredictable and no reliable genetic marker is available for prognostication in desmoid disease.

Current ideas in desmoid tumours.

Desmoid tumours are rare neoplasms of fibroblastic origin which arise with disproportionate frequency in patients with familial adenomatous polyposis (FAP). They are thought to develop in about 10-25% of FAP patients and may be the leading cause of death amongst those who have undergone colectomy. Risk factors include trauma, having a distal germline APC mutation, having a family history of desmoids, and probably oestrogens. In very high-risk individuals there may be a case for delay of colectomy or chemoprophylaxis at the time of surgery. Desmoids are now known to be true neoplasms but with normal telomere length and telomerase activity. FAP-associated tumours seem to carry biallelic APC mutations, one of which lies in the distal part of the gene. Such loss of wild-type APC seems to occur relatively late in tumour development. It is likely that beta-catenin plays an important role in tumourigenesis. FAP-associated desmoids tend to arise in the abdomen or abdominal wall. CT scanning gives the best information on tumour anatomy whilst T2-weighted MRI indicates likely behaviour. Treatment may simply consist of observation. Otherwise, usual first-line therapy is with sulindac with or without an anti-oestrogen. Cytotoxic chemotherapy is an option in unresectable tumours. Surgery is a reasonable first-line treatment in abdominal wall tumours but is risky for intra-abdominal tumours and may necessitate massive small bowel resection. Desmoids are the greatest remaining challenge in the management of FAP and further research into their aetiology needs to be combined with multicentre clinical trials of new treatments in order to improve management of the disease.

[Desmoids tumors]. / Tumeurs desmoïdes.

Desmoid tumor can be defined as a pseudoencapsulated infiltrative growth of well-differentiated collagenous fibroblasts and fibrocytes arising either in fascia or musculoaponeurotic structures. The etiology of desmoid tumors is poorly defined. The most commonly implicated etiologic factors are trauma, hormonal disturbances, and genetic or hereditary factors. Desmoid tumors of the anterior abdominal wall are much less common than extra-abdominal desmoids; they may occur at any age but are most common in the third and fourth decades. Although both sexes may be affected, abdominal desmoids predominate in females, particularly in females of childbearing age. Extra-abdominal desmoids, which most commonly occur on the back, chest wall, head and neck, or lower extremity, have a male predominance. Most patients complain of a painless mass of several months or years' duration. The primary consideration in surgical treatment of desmoid tumors should be the prevention of local recurrence. In most instances, this can be achieved by wide local excision or muscle group resection. There is no clear evidence that irradiation or chemotherapy are effective in controlling desmoid tumors.

Primary mesenteric fibromatosis.

Primary mesenteric fibromatosis is a rare condition. We report a 46-year-old man with this condition.

Disorders of the rectus abdominis muscle and sheath: a 22-year experience.

OBJECTIVES: To determine the spectrum of diseases that can involve the rectus abdominis muscle and sheath (RMS) and to describe the clinical features of these conditions. METHOD: A retrospective medical record review of RMS disorders seen at The New York Hospital-Cornell Medical Center from 1971 to 1992. RESULTS: A total of 40 patients with diseases of the RMS were identified. Thirty patients had primary diseases of the RMS, most commonly desmoid tumor and hematoma. Secondary disorders of the RMS included abscesses from diverticulitis, a perforated sigmoid carcinoma, gallbladder empyema, and disseminated actinomycosis. Eleven of 18 patients with desmoid tumors had familial adenomatous polyposis (FAP). The desmoid tumors in patients with FAP resulted in greater morbidity and mortality than those in patients without FAP. All patients with hematomas were on anticoagulation or had a history of trauma, vigorous coughing, or physical exertion. CONCLUSIONS: 1) RMS disease should be suspected in patients with a palpable abdominal mass and a history of familial adenomatous polyposis, trauma, anticoagulation, or vigorous coughing or exercise. 2) The most common non-neoplastic condition of the RMS is a hematoma. 3) The desmoid tumor is the most common neoplasm of the RMS. 4) Abdominal ultrasonography and CT readily distinguish RMS disease from intraabdominal pathology.

CT of intraabdominal desmoid tumors: is the tumor different in patients with Gardner's disease?

OBJECTIVE: A retrospective study of abdominal CT scans of patients with proved intraabdominal desmoid tumors was done to determine if any objective characteristics exist to differentiate desmoids related to Gardner's syndrome from isolated desmoids. Because the desmoid tumors of Gardner's syndrome can predate the diagnosis of Gardner's syndrome, it would be helpful to know which patients with desmoids need careful follow-up studies as well as initial workup for Gardner's syndrome and all its ramifications. Also, it would be important to differentiate benign from malignant desmoids associated with Gardner's syndrome. It was hoped that the location, enhancement characteristics, and/or the presence or absence of infiltration might be of value. We were interested in noting if, over time, the growth characteristics of desmoids found in Gardner's syndrome were different from those of isolated desmoids. MATERIALS AND METHODS: We reviewed 101 abdominal CT scans obtained in 23 patients during a 13-year period. Forty desmoid tumors were intraabdominal, including 30 lesions associated with Gardner's syndrome in 13 patients and 10 desmoids of the idiopathic form in 10 patients. These tumors were studied to define location; whether they were single or multiple; and whether they had any specific CT characteristics regarding margins, attenuation numbers, or contrast enhancement. RESULTS: Desmoid tumors associated with Gardner's syndrome were more likely to be multiple (38%, five of 13 patients) and to involve the mesentery (60%, 18 of 30 tumors) and the abdominal wall (40%, 12 of 30 tumors), whereas isolated desmoid tumors were singular (all 10 patients) and were located in the retroperitoneum (six cases), pelvis (three), and anterior wall (one). Desmoids related to Gardner's syndrome also tended to be smaller (mean diameter, 4.8 cm) than idiopathic desmoids (mean diameter, 13.8 cm). No differentiating CT characteristics regarding margins, attenuation numbers, or response to contrast material were ascertained. Ten new lesions (seven intraabdominal, three mesenteric) developed in three patients with Gardner's syndrome, whereas no new intraabdominal lesions developed in patients with idiopathic desmoids. Follow-up data on 16 surgically resected desmoids in nine patients (seven with Gardner's syndrome and two with isolated desmoids) revealed seven local recurrences (two in the two patients with isolated desmoids and five in two patients with Gardner's syndrome). CONCLUSION: No CT characteristics, such as attenuation values, margins, and response to the contrast material, were found that would enable differentiation between isolated intraabdominal desmoids and those associated with Gardner's disease. Desmoid tumors associated with Gardner's syndrome tend to occur in the mesentery and abdominal wall, whereas isolated desmoids involve the retroperitoneum and pelvis. When studying CT scans obtained over time, new lesions were noted to develop in a few of the patients with Gardner's syndrome (three of 13), whereas no new lesions were found in patients with isolated desmoids.

Mesenteric fibromatosis.

The authors present the case of a 13-year-old boy in whom, after irradiation for Hodgkin's disease and exploratory laparotomy, mesenteric fibromatosis developed. The "tumor" was resected, and 1 year postoperatively the patient is well.

[The therapeutic procedure for desmoids in patients with diffuse polyposis of the large intestine]. / Lechebnaia taktika pri desmoidakh u bol'nykh diffuznym polipozom tolstoi kishki.

Desmoid was diagnosed in 54 out of 632 patients who had been operated on for diffuse polyposis. The age of patients with desmoid ranged from 18-61 years. Twenty of them had desmoid in the anterior abdominal wall whereas 30--in the small intestine mesentery or retroperitoneal space. Dissection was carried out in 14 out of 18 patients with anterior abdominal wall desmoid. Recurrence was registered in 6 patients. Dissection was attempted in 12 out of 26 patients with intraabdominal desmoid but radical procedure could be performed in 5 only. In a group of 4 patients with synchronous desmoid of both sites, both tumors were removed in one patient only whereas in the other 3--only anterior abdominal wall tumor could be dissected.