Omental liposarcoma; a rare complication in neurofibromatosis type 1

Ultrasonographic findings and diagnosis of omental dedifferentiated liposarcoma: a case report

Liposarcoma is one of the most common types of soft tissue sarcomas and can develop at any site, although omental liposarcoma is extremely rare. Omental liposarcoma has a poor prognosis because the diagnosis is difficult, until it presents as a large tumor causing severe noticeable clinical symptoms. A 51-year-old male with lower abdominal pain was referred to our clinic. Abdominal ultrasonography revealed an ill-defined, solid, heterogeneous, and hypoechoic tumor deep in the lower abdomen. Generally, liposarcomas are hyperechoic, though 20% of liposarcomas present as hypoechoic tumors. This variation might occur depending on the pathological classification. We should consider the possibility of a dedifferentiated component if ultrasonography reveals typical features of soft tissue sarcoma with hypoechoic lesion.

Resection of liposarcoma of the greater omentum: A case report and literature review

INTRODUCTION

Liposarcoma usually occurs in the retroperitoneum and limbs. Liposarcoma of the greater omentum is rare, and most information of such liposarcomas has come from case reports.

PRESENTATION OF CASE

A 60-year-old woman was found to have an 8-cm intra-abdominal mass (suspected lipoma) by computed tomography. At the age of 63 years, she underwent a medical examination and a mass was palpated in the abdomen. Contrast-enhanced computed tomography and magnetic resonance imaging confirmed the presence of a huge intra-abdominal tumor with the omental artery passing through the mass. The tumor was simply resected. Histopathologically, the tumor was diagnosed as a well-differentiated liposarcoma, and the resection margin was microscopically negative. The patient had developed no recurrence or complications 9 months postoperatively.

DISCUSSION

Liposarcoma of the greater omentum is rare, and differentiation of liposarcoma from other tumors is challenging. Adjuvant therapy has not been established as an effective treatment, and radical (R0) resection of the tumor is recommended. Our case of liposarcoma of the greater omentum was surgically managed with good outcomes.

CONCLUSION

The diagnosis of liposarcoma with a lipomatous tumor is challenging, and resection should be considered for huge intra-abdominal lipomatous tumors.

Coincident liposarcoma, carcinoid and gastrointestinal stromal tumor complicating type 1 neurofibromatosis: Case report and literature review

Neurofibromatosis type 1 (NF1) is associated with increased risk of multiple neoplasms. We present a case of a female patient with NF1 who presented with a rectal low-grade neuroendocrine (carcinoid) tumor. Computed tomography imaging found a well-differentiated liposarcoma and a well-circumscribed gastro-intestinal stromal tumor (GIST). Although GIST and carcinoid tumors are frequently found in NF1 patients, liposarcoma complicating NF1 is quite rare and this is the first reported case of well-differentiated liposarcoma in NF1. In summary, we report a case of coincident abdominal carcinoid tumor, GIST and well-differentiated liposarcoma, which illustrates the variability of neoplasms in NF1 patients.

Recurrent retroperitoneal liposarcoma in a patient with neurofibromatosis type I

INTRODUCTION

Liposarcoma complicating neurofibromatosis is very rare. Only a few cases have been described until now. We present a case of recurrent dedifferentiated retroperitoneal liposarcoma in a patient with neurofibromatosis type I (NF-1).

CASE PRESENTATION

A 47-year-old Caucasian woman with NF-1 presented to the hospital initially complaining of left lumbar pain irradiating to the anterior thigh and knee. Physical examination showed atrophy of the lower extremities bilaterally and decreased motor strength on the left lower extremity. Radiological studies demonstrated an enhancing lesion in the left paraspinal region, suggesting malignancy. The patient underwent local resection of tumour with safety margins. Pathological examination was consistent with dedifferentiated liposarcoma (DDLS) with positivity for MDM2 and CDK4 markers. No evidence of metastasis was noted on the radiological studies. The final diagnosis was DDLS, high-grade (G3), pT2bN0M0, stage III. After 6 weeks post-tumour resection, the patient experienced recurrence of malignancy. Chemotherapy with cisplatin and doxorubicin was initiated in the patient.

CONCLUSIONS

Liposarcoma in the context of neurofibromatosis is very rare. To the best of our knowledge, only six cases have been reported until now in the literature. We are presenting this case to underline the possibility of recurrence in the case of retroperitoneal DDLSs despite local tumour resection. Also, although the role of chemotherapy is controversial we decided to start treatment with cisplatin and doxorubicin given the success of chemotherapy in similar case presentations.

Liposarcoma of the forearm in a man with type 1 neurofibromatosis: a case report

Introduction

The combination of neurofibromatosis and liposarcoma is very rare. We present a case of a dedifferentiated liposarcoma in the forearm, as a complication in a patient with neurofibromatosis type 1.

Case presentation

A Caucasian man with neurofibromatosis type 1 presented at our clinic complaining of a slow growing swelling on his left forearm over a period of one and a half years. Clinical examination and history pointed to malignancy. Radiological examination inclusive of magnetic resonance imaging and positron emission tomography confirmed our suspicion. A final diagnosis of dedifferentiated high-grade liposarcoma with axillary lymph node metastases was established after a pathological examination of a tumour biopsy. The consulting tumour board recommended either an elbow exarticulation or an accurate radical local resection including the metastatic axillary lymph nodes. Fortunately, we were able to perform an R-zero resection and the forearm could be saved. The treatment was completed with postoperative radiotherapy of the left forearm's operative bed, the left axillary and the supraclavicular regions. The patient decided against adjuvant chemotherapy.

Conclusion

Liposarcoma complicating neurofibromatosis type 1 is a very rare combination. Up to now, only five cases have been reported in the literature. We are adding a new case to this short list to stress the importance of early recognition. It is the first known case with this disease combination in an upper extremity. Liposarcoma is usually treated by surgery followed by radiotherapy. The role of chemotherapy is controversial and should be based on a decision made on a case-by-case basis.