Single-center experience with intra-abdominal liposarcoma: Optimal minimum duration for postoperative remnant tumor screening

Maximum standardized uptake value on 18F-fluorodeoxyglucose positron emission tomography/computed tomography improves outcome prediction in retroperitoneal liposarcoma

While ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) has been investigated in extremity sarcomas, there is no evidence on its usefulness in retroperitoneal sarcoma. This study was designed to evaluate the usefulness of ¹⁸F-FDG PET/CT in predicting aggressiveness of retroperitoneal liposarcoma. Patients experienced surgery for retroperitoneal liposarcoma from November 2007 to February 2018 and underwent preoperative ¹⁸F-FDG PET/CT were included. Preoperative maximum standardized uptake value (SUV_max) was calculated. To evaluate the predictability of SUV_max for Fédération Nationale des Centres de Lutte Contre le Cancer (FNCLCC) grade 3, receiver operating characteristics (ROC) curve analysis was performed. To analyze whether SUV_max can be a risk factor for prognosis, multivariable Cox regression was performed including potential risk factors regarding operation and histopathology. A total of 133 patients were included. ROC curve showed area under the curve of 0.877 (P < 0.001), with a cut-off point of 4.5 SUV_max showing 85.7% sensitivity and 78.3% specificity. Cox analyses showed that SUV_max > 4.5 was a significant factor for recurrence-free survival (HR = 2.148, CI 1.301-3.546, P = 0.003) and overall survival (HR = 5.052, CI 1.854-13.766, P = 0.002). SUV_max is highly predictive of FNCLCC grade 3 and SUV_max > 4.5 can be used as a prognostic factor before obtaining the histopathology.

Giant primary liposarcoma of the anterior mediastinum: A case report

RATIONALE

Liposarcoma is a cancerous mesenchymal tumor and the most common soft-tissue sarcoma that starts in the adipose tissue. Liposarcoma is commonly found in lower extremities and retroperitoneum, but rarely occurs in the mediastinum.

PATIENT CONCERNS

A 63-year-old male was referred to our clinic with a 6-month history of chronic cough and dyspnea.

DIAGNOSE

Chest x-rays demonstrated a large mass occupying the left hemithorax. Contrast-enhanced computed tomography (CT) revealed a large mass in the anterior mediastinum, which caused the extrinsic compression of the main and left pulmonary artery and the right shift of mediastinum. Diagnosis of liposarcoma was confirmed by microscopic examination and immunohistochemistry analysis.

INTERVENTIONS

The patient underwent a thoracotomy for resection of the mediastinal lesion via left thoracic approach.

OUTCOMES

The patient discharged without any complications and has been continuing to follow up in clinic without any complaints.

LESSONS

The primary mediastinal liposarcoma is rare, and we recommend that the liposarcoma should be considered in the differential diagnosis of a patient presenting with a mediastinal mass.

Hibernation of masses suspected to be remnant tumors after surgical resection of retroperitoneal liposarcoma is related to improved overall survival

BACKGROUND

Although complete surgical resection is considered the best treatment for retroperitoneal liposarcoma, it is related to a high local recurrence rate. This study analyzed patterns of recurrence of retroperitoneal liposarcoma.

METHODS

Records of patients who experienced recurrence after surgery for retroperitoneal liposarcoma from January 2000 to May 2017 were analyzed. Site, number, and characteristics of recurrent mass on computed tomography were serially collected. If a mass did not change size, it was considered a hibernating mass. Potential prognostic factors for overall survival were calculated using Kaplan-Meier survival log-rank tests.

RESULTS

A total of 74 patients, 28 within 6 months and 46 after 6 months, were detected as having a recurrence-suspected mass after surgery. Hibernation of a recurrence-suspected mass was found in 19 patients, 12 within 6 months and 7 after 6 months. While the presence of hibernation was not related to overall survival (P = 0.245), it was significantly related to improved survival in patients with a mass detected within 6 months (P = 0.022). Hibernation was not related to improved survival in patients with a mass detected after 6 months (P = 0.056).

CONCLUSIONS

Hibernation of a recurrence-suspected mass was related to improvement of overall survival in patients with a mass detected within 6 months. This specific patient group should be monitored with care to see if the size of the mass increases. When a mass seemed to be hibernating, a favorable prognosis could be expected.