Multifocal myxoid liposarcoma--metastasis or second primary tumor?: a molecular biological analysis

Multivisceral resection for retroperitoneal liposarcoma-is it worth it? A 20-year single-center experience

PURPOSE

Soft tissue sarcomas are rare malignant tumors. Liposarcoma constitutes the most frequent histological subtype of retroperitoneal sarcoma. The prognosis of soft tissue sarcomas depends on clinical and histologic characteristics.

OBJECTIVE

Evaluate variables that may be related to the overall and local recurrence-free survival in patients with retroperitoneal liposarcoma and discuss the need for visceral resection en-bloc for tumors.

METHODS

A retrospective analysis was conducted of the medical records of 60 patients seen between 1997 and 2017 who underwent surgical resection of retroperitoneal liposarcoma.

RESULTS

The overall survival rate at 5 years of follow-up was 75.22% (95% confidence interval [CI] 0.58-0.86). The probability of a local recurrence-free survival at 5 years of follow-up was 26.04% (95% CI 0.11-0.44). The multivariate analysis showed that dedifferentiated or pleomorphic tumors and R2/fragmented resection were associated with a shorter time to recurrence. No other characteristics markedly influenced the overall survival (P > 0.05).

CONCLUSION

Patients with dedifferentiated or pleomorphic tumors and incomplete resection were associated with higher local recurrence rates than others. This study reinforces the need for complete and en-bloc resection with organs when there is clear involvement or technical surgical difficulty to maintain the tumor integrity.

Liposarcoma of gallbladder: a case report and literature review

A 53-year-old man with prior history of resection of liposarcoma in his leg presented with gallbladder mass. Computed tomography showed 4-cm tumor at gallbladder fundus with weak enhancement with IV contrast. Differential diagnoses included hemangioma and liposarcoma, and laparoscopic cholecystectomy was recommended. In the operating room, the tumor appeared without serosal and liver invasions and uncomplicated laparoscopic cholecystectomy was completed. Histopathological examination revealed the tumor as myxoid liposarcoma with round cells. Adjuvant chemotherapy was not given, and he was placed on imaging surveillance. At 16 months after the operation, he developed recurrence of liposarcoma in the left popliteal fossa.

Myxoid Liposarcoma Metastasizing to the Parotid Gland

Localization of metastases into the parotid gland is a very uncommon event. Usually they arise from primary tumors located in the head and neck, mainly melanoma or epidermoid carcinoma of the skin, while other histotypes, from others anatomical districts, hardly have a metastatic spread to the parotid. Myxoid liposarcoma (MLS) is a rare malignant tumor of the soft tissue that mainly occurs in the extremities, representing the second most common subtype of liposarcoma. Although it is typical for liposarcomas to metastasize to the lungs, it is known that MLS can spread also to extra pulmonary sites. The authors report a case of myxoid liposarcoma of the left thigh in a 64-year-old man, with an unusual metastatic double presentation to the contralateral forearm first and to the parotid gland then. MLS with metastatic disease to the parotid gland is an extremely rare event with very few cases reported in the English literature.

A Neglected Case of Multifocal Liposarcoma Presented in Five Different Sites in a Syrian Woman: A case report

INTRODUCTION

Multifocal soft tissue sarcoma is a rare clinical entity occurring in 1 % of patients with extremity soft tissue sarcoma and in 4.5 % of patients with liposarcoma. Multifocal disease may arise either synchronously or metachronously and has been associated with poor prognosis.

CASE PRESENTATION

Herein, we report a rare case of a Syrian woman patient with six different foci of liposarcoma in five sites at the time of diagnosis.

DISCUSSION

Liposarcomas are currently classified into four different subtypes based on histologic or genetic analysis according to the World Health Organization (WHO), including cell-differentiated, dedifferentiated, myxoid, and pleomorphic. In the present work, we report a neglected patient with a multicentric round cell liposarcoma in five different sites.

CONCLUSION

Medicine cannot provide much care for these advanced cases of multicentric liposarcoma so far. Therefore, more research should be conducted to improve the ability to manage these entities and to identify potential novel therapies.

Myxoid liposarcoma: local relapse and metastatic pattern in 43 patients

BACKGROUND

Liposarcomas are the second most common type of soft tissue sarcomas, 30-50% of these are of myxoid subtype. The aim of this retrospective study was to analyze the local control rate, the metastatic pattern and survival of patients in a consecutive single-institution series.

METHODS

From 1983 to 2015, 43 patients with myxoid liposarcoma of the extremities and trunk wall underwent resections. The margin was defined as R0 (wide) or R1 (marginal). Patients were followed for evidence of local recurrence or distant metastasis. Overall and recurrence-free survival was calculated.

RESULTS

The mean age was 48.6 years. The lower extremity was involved in 40 cases, the mean tumour size was 12 cm. In 31 cases a wide and in 12 cases a marginal resection was performed. Grading was G1 in 14, G2 in 25 and G3 in 4 cases. Nine patient died in follow-up, 4 of them with metastatic disease, all nonpulmonary. 5-year local recurrence (LR) free survival was 82%. 4 (9.3%) patients developed LR (all R1). Overall survival (OS) was 81% after 5 and 72% after 10 years. In multivariate analysis age and Grading proved to be significant on OS. According to univariate analysis, only age over 48 years and distant metastasis had a significant impact on overall survival.

CONCLUSIONS

Patients with myxoid liposarcomas have a good prognosis. Myxoid liposarcoma has a distinct pattern of nonpulmonary metastatic disease. Therefore, patients with high-risk extremity myxoid liposarcoma should undergo imaging studies of the chest, abdomen, spine and pelvis as part of their staging and follow-up examinations preferably with whole body MRI, or CT scans and MRI of the spine and pelvic region for detection of suspected metastatic disease.

Establishment and characterization of a new human myxoid liposarcoma cell line (DL-221) with the FUS-DDIT3 translocation

Myxoid liposarcoma has the pathognomonic fusion oncogene FUS-DDIT3 encoding a chimeric transcription factor. Metastatic risk is higher with an increased round cell component and has been linked to aberrations involving the IGFR/PI3K/AKT pathway. These molecular insights have yet to translate to targeted therapies, and the lack of experimental models is a major hindrance. We describe the initial in-depth characterization of a new cell line (DL-221) and establishment of a mouse xenograft model. The cell line DL-221 was derived from a metastatic pleural lesion showing myxoid and round cell histology. This newly established cell line was characterized for phenotypic properties and molecular cytogenetic profile, using PCR, COBRA-FISH, and western blot. Next-generation whole-exome sequencing was performed to further characterize the cell line and the parent tumor. NOD-SCID-IL2R gamma knockout mice were xenograft hosts. DL-221 cells grew an adhering monolayer and COBRA-FISH showed an aneuploid karyotype with t(12;16)(q13;p11) and several other rearrangements; RT-PCR demonstrated a FUS-DDIT3 fusion transcript type 1. Both the cell line and the original tumor harbored a TP53 compound heterozygous mutation in exon 4 and 7, and were wild-type for PIK3CA. Moreover, among the 1254 variants called by whole-exome sequencing, there was 77% concordance between the cell line and parent tumor. The recently described hotspot mutation in the TERT promoter region in myxoid liposarcomas was also found at C228T in DL-221. Xenografts suitable for additional preclinical studies were successfully established in mice after subcutaneous injection. The established DL-221 cell line is the only published available myxoid liposarcoma cell line that underwent spontaneous immortalization, without requiring SV40 transformation. The cell line and its xenograft model are unique and helpful tools to study the biology and novel potential-targeted treatment approaches for myxoid liposarcoma.

Metachronous Bilateral Extremity Soft Tissue Sarcomas

BACKGROUND

Soft tissue sarcomas (STS) account for approximately 1% of adult malignancies, with 50 to 60% occurring in the extremities. Liposarcoma is the most common type of STS and represent about 20% of total adult sarcomas. There are rare syndromes associated with increased risk of developing STS. Further, chemical compounds such as chlorinated phenols and a few chemotherapeutic drugs have been linked to STS, along with ionizing radiation. Nevertheless, the etiology is uncertain for most of these lesions.

CASE REPORT

This report details 2 cases of metachronous bilateral STS of the lower extremities. The first of these presented as a local recurrence of a previously resected right thigh liposarcoma and a new liposarcoma in the left thigh. As mentioned above, among the different subtypes of STS, liposarcoma has the highest tendency for multifocality. The second patient had multifocal metachronous leiomyosarcoma with lung metastases occurring simultaneously with the second presentation. Leiomyosarcoma is another subtype reported to present with multifocal disease.

CONCLUSIONS

Despite the rarity of bilateral lesions, their occurrence should not be overlooked in the initial diagnosis and follow-up of the initially detected tumor. Early detection can affect patient survival because their presence predicts unfavorable outcomes.

Contemporary diagnostics: sarcoma pathology update

Sarcoma diagnosis continues to evolve as new information is discovered. Certain tumors have been downgraded (dermal leiomyosarcoma) and an atypical category designed for others. Recently entities include myxoinflammatory fibroblastic sarcoma, myoepithelioma, and pseudomyogenic hemangioendothelioma. The terms malignant fibrous histiocytoma and hemangiopericytoma are outdated. New immunostains (STAT6, SOX10, ERG) add diagnostic specificity, and new risk assessment models are described for sarcomas where grading and staging has failed to provide adequate prognosis.

Metachronous multifocal myxoid liposarcoma involving the gastrointestinal tract. Management and literature review

Multifocal soft tissue sarcoma is a rare clinical entity occurring in 1% of patients with extremity soft tissue sarcoma and in 4.5% of patients with liposarcoma. Multifocal disease may arise either synchronously or metachronously and has been associated with poor prognosis. Herein, we have described a rare case of metachronous multifocal myxoid liposarcoma involving the gastrointestinal tract that developed 14 months after the resection of a myxoid buttock liposarcoma. Diagnostic evaluation and management of the patient are discussed along with a review of the relevant literature. We conclude that multifocal myxoid liposarcoma is a rare clinical entity that usually represents metastatic disease with poor prognosis. A thorough imaging and careful physical examination are essential in the preoperative evaluation and postoperative follow-up of patients with myxoid extremity liposarcomas, as these tumors are known to have a tendency to spread toward extrapulmonary sites, frequently without pulmonary metastases.

Novel systemic therapies in advanced liposarcoma: a review of recent clinical trial results

Liposarcoma is one of the most common adult soft tissue sarcomas an consists of three histologic subtypes (well and dedifferentiated, myxoid/round cell, and pleomorphic). Surgery is the mainstay of treatment for localized disease; however for unresectable or metastatic disease, effective treatment options are currently limited. In the past decade, a better understanding of the distinct genetic and molecular aberrations for each of the three histologic subtypes has led to the development of several novel systemic therapies. Data from phase I and early phase II clinical trials have been reported. Despite challenges with conducting clinical trials in liposarcoma, preliminary results for several of these novel, biology-driven therapies are encouraging.