Desmoid tumor: prognostic factors and outcome after surgery, radiation therapy, or combined surgery and radiation therapy

Long-term follow-up of a recurrent multifocal desmoid tumour treated with tamoxifen: a case report

We report a long-term follow-up of a female patient with a multifocal extremity desmoid tumour. She had 3 local recurrences after excision and developed a second unresectable pelvic tumour that has remained unchanged in size for 14 years since starting tamoxifen treatment.

Desmoid tumor with ossification in chest wall: possible involvement of BAMBI promoter hypermethylation in metaplastic bone formation

A rare case of desmoid-type fibromatosis with focal metaplastic bone in the chest wall suggested that enhanced responsiveness to BMP signaling by decreasing BAMBI expression through promoter hypermethylation plays a crucial role in the formation of metaplastic bone.

INTRODUCTION

Desmoid-type fibromatosis, originating from mesenchymal cells with myofibroblastic features, is a locally aggressive and frequently recurring infiltrative lesion. One such sporadic case with metaplastic ossification in the chest wall is presented.

MATERIALS AND METHODS

A 43-year-old man was referred to the hospital with a gradually enlarging hard mass in the left anterolateral chest wall. A thoracotomy was carried out, and histopathological specimens were used for immunohistochemical, genetic, and methylation studies.

RESULTS

Accumulation of altered beta-catenin associated with a somatic heterozygous activating mutation in codon 41 was detected in the typical desmoid-type fibromatosis and at the ossifying focus. Among factors related to bone formation and the classical wnt-beta-catenin signaling pathway, BMP and activin membrane-bound inhibitor (BAMBI) expression was specifically downregulated at the ossifying focus. Hypermethylation of the BAMBI promoter was observed in microdissected tissue from the ossifying focus but not in that from the typical desmoid-type fibromatosis.

CONCLUSIONS

Because both BMP and classical Wnt/beta-catenin/LEF1 signaling cooperatively and mutually induce differentiation of mesenchymal cells into osteoblastic cells and promote bone formation, the epigenetic event leading to the enhanced responsiveness to BMP signaling may play a crucial role in the formation of metaplastic bone.

Desmoid tumours of the extremities and trunk: a review of the literature

Desmoid tumours are rare neoplasms that display local aggressiveness but no propensity to metastasise. They are mainly localized in the abdominal wall, the bowel, and the mesentery or in extra-abdominal sites such as the trunk and the extremities. Surgical resection is the main treatment modality in extremities and trunk, with the optional combination of radiotherapy and/or chemotherapy. However, these tumours have a high propensity for recurrent growth.

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.

Agressive fibromatosis involving the mandible—Case report and review of the literature

BACKGROUND

Aggressive fibromatosis (AF) involving the mandible is rare, and surgery is often complicated by a high recurrence rate.

CASE REPORT

A 4-year-old boy was referred because of a fast growing painless mass which involved the entire left angle of the mandible. Excisional biopsy revealed AF, and local excision of the tumor was performed. Six months after surgery a recurrence was detected. The tumor was determined to be unresectable and the boy was treated with low-dose chemotherapy including methotrexate and vinblastine for 1 year. With combined chemotherapy and surgical debulking, mutilating surgical resection will be delayed as long as possible or until completion of facial growth.

CONCLUSION

According to the literature, surgery is the most common treatment of AF in the head and neck region. However, particularly in children, alternative modes of therapy must be considered because of the high recurrence rate and to avoid mutilating operations.

Full-term gestation and transvaginal delivery after wide resection of an abdominal desmoid tumor during pregnancy

A 29-year-old female was diagnosed with a symptomatic, extra-abdominal desmoid tumor during the first trimester of pregnancy. Computerized tomography (CT) and transabdominal ultrasound (US) noted a mass within the left rectus sheath measuring up to 15 cm in greatest diameter, with mild compression of the uterus. Preoperative diagnosis was confirmed by core-needle biopsy of the lesion. At 20-weeks gestation, wide local resection of the tumor with disease-free margins, as well as abdominal wall reconstruction with polytetrafluoroethylene (PTFE) mesh was successfully undertaken. Histological examination of the tumor ex vivo confirmed that the lesion was a desmoid tumor consisting of spindle cells with dense infiltrating collagenous fibers. Subsequent to her resection, the patient completed a full-term pregnancy without complication, and proceeded with a complication-free transvaginal delivery at 39 weeks. This case illustrates the probable contribution of estrogens towards desmoid tumor development, the durability of abdominal wall reconstruction when subjected to the extraordinary strain of both a gravid uterus and labor, as well as the safety and efficacy of aggressive surgical therapy during pregnancy.

1,25-Dihydroxy vitamin D3: can it be an effective therapeutic option for aggressive fibromatosis

Aggressive fibromatosis (AF), also known as desmoid tumor is a monoclonal fibroblastic proliferation in a collagen matrix that arises in musculoaponeurotic structures. Though considered as benign, they are locally invasive and their propensity for recurrence after conservative surgery is well documented. Addition of postoperative adjuvant radiotherapy produces higher local control rates, although recurrence rates are still high in patients with positive margins. The antineoplastic activity of vitamin D has been demonstrated both in vitro and in vivo models of several cancers. The proposed mechanisms for antineoplastic activity include inhibition of proliferation associated with cell cycle arrest, induction of apoptosis and reduction in invasiveness and angiogenesis. It has also been shown that vitamin D has a negative impact on collagen homeostasis by inhibiting the formation and increasing its degradation. Since vitamin D has an antineoplastic activity and negative effect on collagen synthesis and deposition, it is proposed that 1,25-dihydroxy vitamin D3 can be a right therapeutic option for the management of desmoid tumors.

Management of sarcomas of the head and neck

Soft tissue and bone sarcomas in the head and neck are rare tumors. The 1000 to 1500 yearly cases in the United States are distributed among at least 10 main histologies and multiple head and neck subsites. Although this makes structured studies difficult to perform and high-level evidence-based treatment algorithms difficult to find, basic treatment recommendations can be made from the existing literature for most histologies and subsites. This paper discusses the epidemiology, natural history, and treatment approaches for several of the most common head and neck sarcomas, including the "adult soft tissue sarcomas," osteosarcoma, chondrosarcoma of the larynx, angiosarcoma, rhabdomyosarcoma, desmoid tumors, and dermatofibrosarcoma protuberans.

The management of extra-abdominal desmoid tumours

We performed a retrospective analysis of 35 cases of desmoid tumours (aggressive fibromatoses) that underwent treatment at our institutions between 1987 and 2002. The purpose was to evaluate the rate of local recurrence of desmoid tumours treated with surgical excision, to assess the impact of surgical margins on local recurrence and to define the role of radiotherapy in the treatment. Nine patients experienced a recurrence at an average of 16 months after initial treatment. Seven of the 15 patients with a less-than-wide margin had a local recurrence. Comparatively, only two of the 20 patients with a wide margin had a local recurrence. Thirty-three of the 35 patients were disease free at the last follow-up. We recommend wide excision with clear margins whenever possible. Marginal resections are appropriate when wide excision would severely compromise the function of the limb. Surgical resections and selective supplementation of adjuvant radiotherapy give excellent control rates.

Comprehensive genetic and endoscopic evaluation may be necessary to distinguish sporadic versus familial adenomatous polyposis–associated abdominal desmoid tumors

BACKGROUND

There are limited data regarding how many patients with desmoid tumors actually represent cases with underlying familial adenomatous polyposis.

METHODS

A proband presenting with desmoid tumors and several of the family members underwent a detailed family history, genetic (adenomatous polyposis coli [APC] gene sequencing), and upper and lower endoscopic evaluation.

RESULTS

The proband's initial diagnosis was of a sporadic desmoid tumor. Colonoscopy was entirely normal. However, on subsequent esophagogastroduodenoscopy, several gastric polyps were found. The proband's mother subsequently underwent colonoscopy and was found to have multiple colon adenomas. On genetic analysis, a deletion of "T" was identified at codon 2645 of the APC gene in the proband. The proband's mother had a normal APC protein truncation test result. However, on full gene sequencing, the mother was found to harbor the same APC gene mutation.

CONCLUSION

A detailed family history and endoscopic and genetic evaluations for patients with desmoid tumors are vital because they may be the sentinel presentation of familial adenomatous polyposis. If confirmed in larger studies, APC full gene sequencing and upper and lower gastrointestinal tract evaluation may need to be part of standard evaluation of patients with abdominal desmoid tumors.

Incidence and treatment of recurrent plantar fibromatosis by surgery and postoperative radiotherapy

BACKGROUND

The incidence of plantar fibromatosis (PF) is unknown. Sometimes PF tends to recur repetitively after surgical treatment. In our institute we have used postoperative radiotherapy in an attempt to diminish the change on recurrence.

METHODS

The Dutch Network and National Database for Pathology (PALGA) was consulted to establish the incidence of plantar fibromatosis (PF). Data from 9 patients (11 feet) with PF referred to our institute for recurrent disease were analyzed and the role of postoperative radiotherapy in prevention of recurrence was studied.

RESULTS

An average of 1.2 operations for PF was performed per 100,000 citizens yearly in the Netherlands. Twenty-six operations were performed and postoperative radiotherapy was used in 6 cases. Plantar fasciectomy was associated with the lowest recurrence rate. After microscopically incomplete excision or excision of early recurrence (< or =6 months) alone all tumors recurred, while recurrence was rarely observed after adjuvant radiotherapy. However, radiotherapy was associated with significantly impaired functional outcome in 3 cases.

CONCLUSIONS

Plantar fibromatosis is relatively rare. Plantar fasciectomy seems to be the operation of choice. Although effective in decreasing the recurrence rate, adjuvant radiotherapy should be used very selectively because of its serious side effects.

Margins in extra-abdominal desmoid tumors: A comparative analysis

BACKGROUND AND OBJECTIVES

The main treatment of extra-abdominal desmoid tumors remains surgery, but recurrence rates up to 80% are reported. The impact of microscopic surgical margin status according to the Enneking classification system is discussed controversially.

METHODS

Therefore, the authors screened the published literature for reliable data on the importance of a wide or radical excision of extra-abdominal desmoid tumors. All studies with more than ten patients, a surgical treatment only, and margin status stated were included.

RESULTS

Only 12 out of 49 identified studies fulfilled the inclusion criteria. One hundred fifty-two primary tumors were excised with wide or radical microscopic surgical margins, while in 260 cases a marginal or intralesional excision was performed. In the first group 41 patients (27%) and in the second one 187 patients (72%) developed a recurrence. Therefore, microscopic surgical margin status according to the Enneking classification system is a significant prognostic factor (P < 0.001).

CONCLUSIONS

The data of this review underline the strategy of a wide or radical local excision as the treatment of choice. Furthermore, as a large number of studies had to be excluded from this analysis, exact microscopic surgical margin status should be provided in future studies in order to allow comparability. .

Desmoid tumour in familial adenomatous polyposis. A review of literature

Desmoid tumours (DT) are rare benign tumours that do not metastasise, but tend to invade locally. DT are frequently seen in patients with familial adenomatous polyposis (FAP), and diagnosis and treatment are often difficult. Surgical trauma, genetic predisposition and hormonal factors are considered to be correlated with the development and growth of DT. In patients with FAP, 50% of the tumours are localised intra-abdominally, and 85-100% of these are mesenteric. DT frequently present as non- tender, slowly growing masses. The symptoms are abdominal pain, vomiting, diarrhoea or haematochezia. Mesenteric DT can cause small bowel obstruction or ischaemia, hydronephrosis or form fistulas. Diagnosis is obtained through biopsy and the extension is determined by a CT-scan. Surgical excision is recommended in patients with DT in the abdominal wall. First line treatment of mesenteric DT is a NSAID in combination with tamoxifen. Surgery may be considered in case of a small and well-defined DT with no signs of invasion of vital structures, and in cases of imminent bowel ischaemia or obstruction. The prognosis in mesenteric DT is serious, and improvement of the therapeutic strategy awaits current international studies.

Preoperative radiotherapy is effective in the treatment of fibromatosis

The use of preoperative radiation is well-established for soft tissue sarcoma, but its use in fibromatosis is not well-characterized. The purpose of this study was to examine the impact of preoperative radiotherapy on the local control of fibromatosis and to assess treatment-related morbidity in this setting. In particular we assessed complication rates in comparison with soft tissue sarcoma treatment. All patients with fibromatosis referred to this unit who received preoperative radiotherapy (50 Gy in 25 fractions) from 1988 to 2000 and who had at least 2 years of followup were included in this study. The rate of recurrence in this group was ascertained. Similarly constructed datasets from all patients with soft tissue sarcomas of the extremities who received preoperative radiation from 1986 to 1997 also were analyzed. The rates of complications in the two groups were compared. Fifty-eight patients were treated with preoperative radiation for fibromatosis and the median followup was 69 months. There were 11 local recurrences (19%). Major wound complications manifested in two patients (3.4%). Wound-related complications arose in 89 of 265 patients with soft tissue sarcomas (33.5%). There was a significant difference in the rate of major wound complications observed in the two groups. The use of radiotherapy before surgery is effective in the combined treatment of fibromatosis.

Pediatric soft-tissue tumors

Soft-tissue tumors in children (<18 years) are a heterogeneous group of lesions. Masses may be asymptomatic or associated with pain or discomfort. Although most lesions are benign, developing an appropriate differential diagnosis requires knowledge of the clinical and radiographic characteristics of tumors and tumorlike conditions in children. A thorough history and physical examination, followed by appropriate imaging studies, when indicated, can establish a correct diagnosis and help determine appropriate treatment recommendations.

Sporadic hereditary pancreatic desmoid tumor: a new entity?

Deeply seated aggressive fibromatosis also termed as desmoid tumors are rare tumors that invade surrounding structures. Although they never metastasize mortality rate may be as high as 10% due to their aggressive local behavior. Intraabdominal desmoid tumors are usually associated with familial poliposis coli and have a high recurrence rate regardless of the therapy instituted. Sporadic cases are very rare and generous surgical excision may be of benefit. We hereby report 2 siblings with sporadic pancreatic desmoid tumors who also harbor additional fibrotic masses in the pelvis. Although in previously reported cases there is usually a triggering event such as trauma, in the present cases there was no inciting event. Furthermore, the cases are without an associated FAP history, which provides the first clinical clue of a possible genetic determinant in this rare disorder.

Desmoid tumor in a scar from radical nephrectomy for renal cancer

Desmoid tumor is a fibroblastic proliferation arising in musculoaponeurotic tissues. We report a case of abdominal desmoid tumor discovered 2 years after radical nephrectomy for right renal cell carcinoma. Surgical extirpation was performed and the patient remained well 2 years later with no evidence of disease. The possibility of desmoid tumors developing in the incised abdominal wall should be considered while following patients after surgery.

Quality of surgery and outcome in extra-abdominal aggressive fibromatosis: a series of patients surgically treated at a single institution

PURPOSE

To explore prognostic factors in surgically treated aggressive fibromatosis (extra-abdominal desmoid tumor).

PATIENTS AND METHODS

A total of 203 consecutive patients treated with surgery over a 35-year period at a single referral center were retrospectively reviewed. One hundred twenty-eight were first seen at our institution with primary disease, whereas 75 had a recurrent tumor. All patients underwent macroscopically complete resection. Margins were rated as negative in 146 (97 with primary tumors, 49 with recurrences) and positive in 57 (31 in primary, 26 in recurrences) patients. Median follow-up was 135 months.

RESULTS

Patients with primary disease had a better disease-free survival rate than those with recurrence (76% v 59% at 10 years). Presenting with a recurrence was also the strongest predictor of local failure in the multivariate analysis. In patients first treated for primary disease, size and site had prognostic significance, whereas microscopically positive surgical margins did not. In contrast, in patients with recurrence, there was a trend toward better prognosis if margins were negative (although this was not significant at multivariate analysis).

CONCLUSION

Presence of microscopic disease does not necessarily affect long-term disease-free survival in patients with primary presentation of extra-abdominal desmoid tumors. Thus, function-sparing surgery may be a reasonable choice when feasible without leaving macroscopic residual disease. In patients with recurrences, positive margins may more clearly affect prognosis, potentially necessitating adjuvant radiation in selected cases.

Extra-Abdominal Fibromatosis: A Case Report

Head and neck fibromatosis is a rare disease with a variable clinical picture. We report the case of a 40-year-old woman who had a 1-week history of a painless mass overlying her right neck. Histology confirmed a diagnosis of extra-abdominal fibromatosis. Two unusual features of this case were the site of the lesion and its rapid growth. In this article, we discuss the clinical picture of head and neck fibromatosis, its etiology and pathology, and current opinion regarding its treatment.

Radiation therapy for soft tissue sarcoma

Sarcomas are relatively uncommon tumors of mesenchymal origin. They may arise anywhere within the musculoskeletal system and are typically classified by clinical behavior into benign, borderline, or malignant. This article focuses primarily on the role of radiation for malignant soft tissue sarcoma and selected borderline tumors.

Preclinical studies of gene transfer for the treatment of desmoid disease in familial adenomatous polyposis

BACKGROUND

Familial adenomatous polyposis (FAP) arises following mutation or loss of the adenomatous polyposis coli (APC) gene. Desmoid tumours are proliferations of fibroblasts and occur as an extracolonic manifestation of FAP. They are a leading cause of death after colectomy. The aim of this study was to assess the potential for APC gene transfer into fibroblasts in vitro and in vivo as a basis for consideration of gene therapy in the prevention or treatment of desmoid tumours.

METHODS

The APC gene was transferred by lipofection into fibroblasts in tissue culture and into peritoneum and small bowel mesentery in vivo. Reverse transcriptase-polymerase chain reaction was used to determine whether or not transfection was successful.

RESULTS

Transgene expression was recorded in vitro to 7 days after transfection. High levels of transgene expression were also seen in samples of peritoneum (all eight mice), small bowel mesentery (seven of eight), liver (seven of eight) and intestinal tissues (five to six of eight) following intraperitoneal treatment. Interestingly, transgene expression in gonadal tissues was occasionally noted.

CONCLUSION

Liposomal transfection of APC gave prolonged high-level expression of the transgene, an important basis for gene therapy. No adverse effects were recorded. Further work is needed in animal models of desmoid disease to assess the clinical effects of gene therapy.

Response of extraabdominal desmoid tumors to therapy with imatinib mesylate

BACKGROUND

Desmoid tumor represents a rare monoclonal neoplasm arising from deep musculoaponeurotic structures and may occur sporadically or in association with the familial adenomatous polyposis and Gardner syndromes. Desmoid tumors do not appear to demonstrate metastatic potential; however, local infiltrative growth results in significant morbidity and potential mortality. Although the delineation of optimal therapy for desmoid tumors has been confounded by several factors, surgical resection with adjuvant radiotherapy for a positive surgical margin remains the standard approach. Responses have been demonstrated to nonsteroidal antiinflammatory agents, antiestrogen compounds, and a variety of other agents in small series. Imatinib mesylate appears to demonstrate inhibitory activity against multiple class 3 receptor tyrosine kinases, including platelet-derived growth factor receptor (PDGFR)-alpha and PDGFR-beta, as well as c-kit.

METHODS

The authors performed immunohistochemical and qualitative real-time polymerase chain reaction analysis on nine desmoid tumor specimens that demonstrated consistent positivity for c-kit as well as PDGFR-alpha and PDGFR-beta. At the time of last follow-up, 2 patients had received therapy with imatinib mesylate at a dose of 400 mg twice daily.

RESULTS

Both patients demonstrated ongoing radiographic and clinical responses with a duration of 9 months and 11 months, respectively.

CONCLUSIONS

Imatinib mesylate has been reported to have activity against desmoid tumor, most likely because of c-kit and PDGFR receptor tyrosine kinase activity inhibition, and warrants further study. The relative novelty of this agent and the lack of long-term toxicity data should prompt its use only in the salvage setting in which established local and systemic approaches fail to control disease. In addition, the use of imatinib mesylate in the treatment of this neoplasm preferably should be in the context of a formal prospective clinical trial.

External beam radiotherapy for primary and adjuvant management of aggressive fibromatosis

PURPOSE

To review a large single-institution experience in the management of aggressive fibromatosis to determine the effectiveness of external beam radiotherapy (EBRT) and identify the presentation and treatment variables predictive of locoregional control.

METHODS AND MATERIALS

Between 1975 and 2000, 72 patients were treated with EBRT for a pathologically confirmed diagnosis of aggressive fibromatosis. Thirty patients were treated at the primary presentation and 42 at the time of a locoregional recurrence. Minimal 2-year follow-up data were available for 65 patients (median 6 years). Megavoltage irradiation with 60Co to 20 MV photons or electron therapy was used for all patients. Most patients were treated after attempted complete surgical resection; 16 patients underwent pretreatment biopsy alone. The prescribed treatment was standard (1.8 Gy) daily fractions in 42 cases and 1.2 Gy fractions b.i.d. in 23 cases. The median prescribed dose was 54 Gy. The prognostic variables and treatment results were evaluated by Kaplan-Meier actuarial analysis.

RESULTS

Locoregional control was achieved in 52 of 65 patients. The 5-year actuarial locoregional control was 83%. Locoregional failure occurred in 13 patients (11 in patients with recurrent tumors). Only two failures occurred within the irradiation fields; nine failures occurred at the field margins. Eleven patients were salvaged by surgery: wide excision in nine and amputation in two. The only prognostic factor significant for locoregional control was primary vs. recurrent presentation (p = 0.0193). The 5-year locoregional control rates for irradiation at initial presentation and at recurrence were 96% and 75%, respectively. The variables without significance for locoregional control included primary tumor location, surgical procedures performed, resection margins, and gross vs. microscopic residual tumor at irradiation. Lymphedema was the most common late effect, occurring in 7 patients, 5 with prior treatment. Bone fracture occurred in 3 patients; all 3 had fibromatosis involving the bone at presentation but without recurrence at the time of fracture.

CONCLUSION

EBRT is effective treatment for aggressive fibromatosis. The probability of locoregional control decreases with multiple prior recurrences.

Desmoid tumors: a novel approach for local control

BACKGROUND AND OBJECTIVES

After resection, desmoid tumors are associated with a recurrence rate that is typically 25-50%. Although this is an unusual problem, we instituted a prospective cohort study with neoadjuvant chemotherapy and radiation, followed by surgical resection, in an effort to improve local control.

METHODS

Between 1985 and 1999, 13 patients with potentially resectable disease were managed with a treatment protocol of preoperative doxorubicin (30 mg continuous infusion daily for 3 days) and radiotherapy (10 x 300 cGy). Resection was performed 4-6 weeks later. All lesions were resected with an intended margin of 1 cm, but clear adventitial margins were accepted in order to preserve critical structures.

RESULTS

The median follow-up was 71 months (range, 22-109). Six patients (46%) presented after failure of a previous surgery. Clear microscopic margins were obtained in 11 patients, and 2 patients had positive margins. There were two local recurrences (15% local recurrence). Both recurrences followed resection of large thigh lesions, which appeared at 30 and 49 months of follow-up. In one patient with a chest wall tumor, two new primary desmoid tumors developed outside the treatment area, in the ipsilateral arm and forearm. Eleven patients have been disease free for a median of 71 months (range, 22-109).

CONCLUSIONS

For potentially resectable lesions, this protocol provides excellent local control, even in those with recurrent disease. Neoadjuvant treatment with doxorubicin and radiotherapy appears to be a better option than surgery alone, or surgery and adjuvant radiotherapy. These results need to be confirmed in larger, prospective randomized trials.

Desmoid tumours

Desmoid tumours exhibit fibroblastic proliferation and arise from fascial or musculoaponeurotic structures. Despite their benign microscopic appearance, and their negligible metastatic potential, the propensity of desmoid tumours for local infiltration is potentially significant in terms of deformity, morbidity and mortality due to pressure effects and obstruction of vital structures and organs. The rarity of desmoid tumours, coupled with the variability in their clinical course, renders these lesions a vexing entity, and makes demonstration of the efficacy of any specific intervention difficult. Failure to recognize the potential for malignant behaviour in this tumour renders desmoids susceptible to inadequate treatment. This distinct pathological entity is reviewed with a specific focus on aetiology and treatment.

Phenotype-genotype correlations in an extended family with adenomatosis coli and an unusual APC gene mutation

PURPOSE

Genotype-phenotype correlations in familial adenomatous polyposis are only partially understood and, in particular, little is known about the biomolecular characteristics of desmoid tumors, which are one of the most serious and frequent manifestations of familial adenomatous polyposis. In the present study, we describe a family with familial adenomatous polyposis, with peculiar clinical characteristics (i.e., frequency and severity of desmoid neoplasms) associated with an unusual mutation of the adenomatosis polyposis coli gene. If confirmed by other investigations, these findings might help to understand the biologic mechanisms by which specific adenomatosis polyposis coli mutations predispose to desmoid tumors.

METHODS

The family with familial adenomatous polyposis, living in southern Italy, was studied from 1985 to the end of 1999; at this date, 15 individuals have been affected by histologically verified familial adenomatous polyposis, 11 of whom had desmoid tumors. A total of 19 family members were studied for adenomatosis polyposis coli gene mutations; 13 of them tested positive and 6 negative. The analytical procedure-previously described-consisted of the extraction of peripheral blood cell DNA, amplification of exon 15 by polymerase chain reaction, single-strand conformation polymorphism analysis, and direct sequencing of the DNA fragment containing the mutation.

RESULTS

The main clinical features of the family were 1) a high frequency of desmoid tumors and, consequently, a high penetrance of the desmoid trait in all branches of the family and in 11 (73.3 percent) of 15 affected individuals and 2) severity of desmoids in at least 4 family members, 2 of whom died for causes related to the presence of these tumors. The molecular basis of the disease was an uncommon mutation of the adenomatosis polyposis coli gene, consisting of a large deletion of 310 base pairs at codon 1,464, with duplication of the breakpoint (4,394ins15del310), leading to a stop codon at position 1,575.

CONCLUSIONS

The present study shows that a truncating mutation in the adenomatosis polyposis coli gene at the beginning of the region frequently associated with desmoids induced a familial adenomatous polyposis phenotype featured by a high penetrance of the desmoid trait, with severe disease in several affected members of both sexes. The study may help to understand the biologic mechanisms of genotype-phenotype correlations in adenomatosis coli.

Low-dose chemotherapy with methotrexate and vinblastine for patients with advanced aggressive fibromatosis

BACKGROUND

This Phase II study was undertaken to assess the activity of methotrexate plus vinblastine in the treatment of patients with inoperable aggressive fibromatosis (AF) and to observe the evolution of the disease after such low-dose chemotherapy.

METHODS

Thirty patients with a median age of 27 years who were affected by primary (20%) or recurrent (80%), advanced, inoperable AF were treated with weekly methotrexate at a dose of 30 mg/m(2) plus vinblastine at a dose of 6 mg/m(2) for a median interval of 1 year. Patients with recurrent disease had received surgery, radiotherapy, tamoxifen, and antracycline-based chemotherapy. Tumor response was assessed in all patients as well as time to disease progression.

RESULTS

Eighteen patients (60%) showed stable disease or minor tumor shrinkage along with symptom relief. A partial response was detected in 12 patients (40%). No complete responses were observed, and no patients had tumor progression during treatment. Four patients received fewer than 15 cycles of chemotherapy, mainly because of severe myelotoxicity. One of these patients died of local disease progression 33 months later, and the other three patients were stable. After a median follow-up of 75 months, the 10-year actuarial progression free interval is 67%.

CONCLUSIONS

Methotrexate plus vinblastine given every 7-10 days for several months is associated with prolonged stable disease in a substantial subset of patients with advanced (inoperable) aggressive fibromatosis.

Desmoid tumors

Because of the wide variety of anatomic locations and patient factors, there is no one treatment that is appropriate for all desmoid tumors. The type of treatment depends on tumor characteristics and location, as well as patient characteristics and preferences. Desmoid tumors can be persistent and frustrating to manage because no one treatment modality offers a high likelihood of remission. Multiple modalities may be necessary in some patients. Although mortality is rare and is usually due to local complications, significant disability or morbidity can result from desmoid tumors, their treatment, and complications arising from treatment. The entire clinical picture and the patient's preferences must be taken into account when deciding on an appropriate treatment plan. Patients with desmoid tumors are optimally managed in a multidisciplinary setting with close collaboration between surgeon, pathologist, diagnostic radiologist, radiation oncologist, and medical oncologist. When possible, surgical resection with negative margins is the preferred modality. When surgical resection with negative margins may prove disabling, surgery can be followed by postoperative radiation, although the role and efficacy of this are controversial. In locations where surgical extirpation is difficult or unfeasible, primary radiation, hormonal therapy, or chemotherapy should be considered. Familiar adenosis polyposis (FAP)-associated mesenteric lesions, sporadic tumors present without change for months or years, or tumors present in areas where progression will not present significant additional morbidity are candidates for observation only.

Gastrointestinal stromal tumor versus intra-abdominal fibromatosis of the bowel wall: a clinically important differential diagnosis

Intra-abdominal fibromatosis (IAF) is an uncommon benign neoplasm that usually occurs in the mesentery or retroperitoneum and may, on occasion, mimic a gastrointestinal stromal tumor (GIST). Differentiating between these two entities is important clinically because IAF is a benign tumor whereas GISTs frequently have malignant potential. In this study, the authors identified 13 cases of IAF with prominent involvement of the bowel wall as well as 35 GISTs of the small intestine, colon, or mesentery and analyzed their clinical, gross, histologic, immunophenotypic, and ultrastructural characteristics to identify important distinguishing features. Patients with IAF were younger (mean, 34 yrs) than patients with GIST (mean, 54 yrs). Both types of tumors tended to be large, but GISTs were soft and lobulated with hemorrhage, necrosis, or cystification whereas IAFs were firm, tan, and homogeneous. Histologic features characteristic of GIST included the presence of spindle or epithelioid cells with variable architecture, mitotic activity (range, <1-95 mitoses/50 high-power fields [hpf]; mean, 15 mitoses/50 hpf), nuclear atypia, and myxoid or hyalinized stroma. Necrosis and hemorrhage were seen in 16 and 25 tumors, respectively. In contrast, IAFs were composed of broad, sweeping fascicles of monotonous spindle cells with mitotic activity (range, <3-11 mitoses/50 hpf; mean, 4 mitoses/50 hpf), bland nuclear features, and finely collagenous stroma. Necrosis, hemorrhage, and myxoid degeneration were not seen. Immunohistochemical studies performed on a limited number of GISTs and IAFs demonstrated that cells expressed vimentin (100% GIST and IAF), CD117 (88% GIST and 75% IAF), CD34 (42% GIST and 0% IAF), smooth muscle actin (63% GIST and 75% IAF), muscle actin (75% GIST and 75% IAF), desmin (8% GIST and 50% IAF), and S-100 protein (16% GIST and 0% IAF). Ultrastructural analysis of 21 GISTs revealed incomplete smooth muscle differentiation in some tumors whereas IAFs were shown to have complete myofibroblastic/fibroblastic differentiation. Information regarding clinical outcome was available on 29 patients and revealed that three patients with histologically benign GISTs were alive with no evidence of disease at 5 months to 6 years (mean, 3.5 yrs) and one patient with a histologically benign tumor died of disease after 7 years. Of patients with histologically malignant GIST, one died of surgical complications, 10 were alive without disease at I to 13 years (mean, 5.4 yrs), four were alive with disease at 4 months to 15 years (mean, 3.8 yrs), three had disseminated disease at operation, and seven were dead of disease at 10 months to 3 years (mean, 2.2 yrs). Follow up of eight patients with IAF demonstrated that five were alive without disease at 4 months to 15 years (mean, 5.3 yrs) and three had recurrences at 1 (two patients) and 2 years (one patient). In summary, IAFs can have many features (large size, infiltration of adjacent structures, mitotic activity) that can cause diagnostic confusion with GISTs and, importantly, the degree of mitotic activity present in IAFs may overlap that seen in malignant GISTs. These entities can be distinguished primarily by their light microscopic and ultrastructural features but there is a notable overlap in their immunohistochemical profiles. The distinction between these neoplasms is important because there are important clinical implications for the patient.

Soft-tissue sarcomas

Sarcomas of the soft tissues are challenging lesions for the surgical oncologist. Careful planning must be done at all stages of diagnosis and treatment, because every sarcoma is unique with respect to histologic type, size, and location. Pretreatment discussions in a multidisciplinary format are useful to ensure appropriate and effective management of these tumors.