The Predictive Role of the Histopathological Scoring System in Adipose Tumors-Lipoma, Atypical Lipomatous Tumor, and Liposarcoma

Lipomatous tumors are the most frequent soft tissue neoplasms. Sometimes their differential diagnosis is difficult to perform only by microscopic analysis. This study aims to create a histopathological scoring system and highlight the impact of intratumoral microvascular density. This study was conducted over 10 years. We analyzed the main pathogenic pathways (MDM2 and CDK4), as well as the tumor microvascularization (CD31 and CD34) by immunohistochemical tests. We also analyzed the status of the MDM2 gene by CISH. These data, together with the clinical and histopathological information, were statistically analyzed by appropriate tests. We identified 112 eligible cases, with most of the patients being in their sixth decade of life, with a slight predominance of the female sex. We found important associations like tumor location linked to nuclear pleomorphism severity and microvascularization density correlated with atypia severity. Also, we observed that a maximum diameter of a tumor of at least 69 mm is associated with the presence of tumor necrosis. The score designed in this study shows an increased sensitivity and specificity for the diagnosis of lipomas (100%, respectively, 97%), atypical lipomatous tumors (93.8%, respectively, 82.3%), and liposarcomas (100%, respectively, 90.5%). This present study enhances the present data by bringing to attention the histopathological score with a role in differential diagnosis, as well as in the prediction of immunohistochemical and genetic tests. Also, we highlighted the importance of microvascular density, especially in the diagnosis of liposarcomas.

Imaging of Soft Tissue Tumors

Differentiation of malignant from benign soft tissue tumors is challenging with imaging alone, including that by magnetic resonance imaging and computed tomography. However, the accuracy of this differentiation has increased owing to the development of novel imaging technology. Detailed patient history and physical examination remain essential for differentiation between benign and malignant soft tissue tumors. Moreover, measurement only of tumor size based on Response Evaluation Criteria In Solid Tumors criteria is insufficient for the evaluation of response to chemotherapy or radiotherapy. Change in metabolic activity measured by ¹⁸F-fluorodeoxyglucose positron emission tomography or dynamic contrast enhanced-derived quantitative endpoints can more accurately evaluate treatment response compared to change in tumor size. Magnetic resonance imaging can accurately evaluate essential factors in surgical planning such as vascular or bone invasion and "tail sign". Thus, imaging plays a critical role in the diagnosis and treatment of soft tissue tumors.

Prediction of Histologic Subtype and FNCLCC Grade by SUVmax Measured on 18F-FDG PET/CT in Patients with Retroperitoneal Liposarcoma

This study aimed to evaluate the usefulness of maximum standardized uptake value (SUVmax) on ¹⁸F-fluorodeoxyglucose positron emission tomography with computed tomography (¹⁸F-FDG PET/CT) in differentiating the subtypes and tumor grades of retroperitoneal liposarcoma (RPLS). The data of RPLS patients who underwent surgical resection from November 2013 to December 2019 at the sarcoma center of our institute were reviewed. The demographics, clinical features, and SUVmax of 84 patients who underwent preoperative ¹⁸F-FDG PET/CT scans were analyzed. Of these, 19 patients (22.6%) were with well-differentiated liposarcoma (WDLPS), 60 patients (71.4%) were with dedifferentiated liposarcoma (DDLPS), and 5 patients (6.0%) were with pleomorphic liposarcoma (PMLPS). The median SUVmax of WDLPS, DDLPS, and PMLPS groups was 2.8 (IQR: 1.9-3.2), 6.2 (IQR: 4.1-11.3), and 4.5 (IQR: 4.0-7.4). The ROC curve suggested 3.8 as an approximate cutoff value of SUVmax for distinguishing WDLPS and non-WDLPS (sensitivity = 0.769; specificity = 0.895). The median SUVmax for FNCLCC Grades 1, 2, and 3 of RPLS was 2.5 (IQR: 1.9-3.2), 4.5 (IQR: 3.2-6.7), and 9.0 (IQR: 6.0-13.3). The ROC curves suggest that SUVmax of ≤3.8 and >5.3 can be used for predicting FNCLCC Grades 1 and 3, respectively. The result showed that ¹⁸F-FDG PET/CT exhibited high sensitivity and specificity for identifying the subtypes and FNCLCC grades of RPLS. Additionally, ¹⁸F-FDG PET/CT might be a useful complementary imaging modality for guiding suitable biopsy location of RPLS.

Resection outcomes for primary and local recurrent retroperitoneal liposarcoma patients

Background

The clinical characteristics of primary retroperitoneal liposarcoma (PR RPLPS) and local recurrent retroperitoneal liposarcoma (LR RPLPS) cases were compared to determine the related factors involved in postoperative survival.

Methods

A total of 90 patients who underwent surgery between 2006 and 2013 were included in this study. Clinicopathological data that was prospectively gathered was analyzed to identify factors associated with overall survival (OS) and progression-free survival (PFS).

Results

The PR cases showed a higher complete resection rate when compared to the LR group. The LR group showed a greater number that were poorly differentiated and highly malignant. More blood loss was observed in the LR compared to the PR group. Multivariate analysis suggested that blood loss and tumor grade were prognostic factors for OS and PFS of the PR group, but extent of resection was a prognostic factor only for OS. In the LR group, the extent of resection was a significant prognostic factor associated with OS, whereas tumor grade was associated with PFS.

Conclusions

Complete surgical resection is the most important factor for the survival of RPLPS patients. Tumor grade is an independent prognostic factor for PFS. In PR RPLPS, poor tumor classification and increased intraoperative bleeding are associated with a poor prognosis.

A recurrent giant retroperitoneal myxoid liposarcoma: a case report and literature review

Retroperitoneal liposarcoma (RPLS) is a very rare type of tumor, accounting for less than 1% of all malignancies, especially the "large retroperitoneal liposarcoma" (GRPLS) of more than 20 kg (kilograms). Herein, we describe the treatment experience in a case of recurrent GRPLS. A 70-year-old woman was admitted with an enlarged abdomen, and computed tomography (CT) showed a large, low-density, homogeneous retroperitoneal mass (40×37×26 cm). In laparotomy, this 55×40×20 cm liposarcoma was completely removed and pathologically diagnosed as low-grade myxoid liposarcoma. The patient did not receive any adjuvant therapy, and CT showed no evidence of recurrence during follow-up.

Parathyroid Auto-transplantation Mimicking Liposarcoma

Parathyroid autotransplantation is an increasingly common procedure given the increasing rate of hyperparathyroidism. However, post-autotransplantation imaging is not commonly performed and the imaging findings can mimic liposarcoma. Therefore, radiologists should be aware of the imaging characteristics of parathyroid autotransplantation. Here we discuss the CT and Tc99m-Sestamibi 4D-CT findings of parathyroid autotransplantation. We will also discuss the pathophysiology of liposarcoma and present the gross histological findings seen on pathology.

Incidentally discovered well-differentiated retroperitoneal liposarcoma with inguinal canal herniation: report of 2 cases

Well-differentiated retroperitoneal liposarcomas are slow growing and low-grade tumors, reaching usually huge size before being symptomatic and so diagnosed, therefore with increase of the surgical risk and of the probability of dedifferentiation. Inguinal location of these tumors is unusual and rarely diagnosed.

Can Abdominal Computed Tomography Imaging Help Accurately Identify a Dedifferentiated Component in a Well-Differentiated Liposarcoma?

PURPOSE

To assess the ability of computed tomography (CT) to differentiate an atypical lipomatous tumor/well-differentiated liposarcoma (WDLPS) from a WDLPS with a dedifferentiated component (DDLPS) within it.

MATERIALS AND METHODS

Forty-nine untreated patients with abdominal atypical lipomatous tumors/well-differentiated liposarcomas who had undergone contrast-enhanced CT were identified using an institutional database. Three radiologists who were blinded to the pathology findings evaluated all the images independently to determine whether a dedifferentiated component was present within the WDLPS. The CT images were evaluated for fat content (≤25% or >25%); presence of ground-glass density, enhancing and/or necrotic nodules; presence of a capsule surrounding the mass; septations; and presence and pattern of calcifications. A multivariate logistic regression model with generalized estimating equations was used to correlate imaging features with pathology findings. Kappa statistics were calculated to assess agreement between the three radiologists.

RESULTS

On the basis of pathological findings, 12 patients had been diagnosed with DDLPS within a WDLPS and 37 had been diagnosed with WDLPS. The presence of an enhancing or a centrally necrotic nodule within the atypical lipomatous tumor was associated with dedifferentiated liposarcoma (P = 0.02 and P = 0.0003, respectively). The three readers showed almost perfect agreement in overall diagnosis (κ r = 0.83; 95% confidence interval, 0.67-0.99).

CONCLUSIONS

An enhancing or centrally necrotic nodule may be indicative of a dedifferentiated component in well-differentiated liposarcoma. Ground-glass density nodules may not be indicative of dedifferentiation.

Organ-sparing Surgery in Treating Patients with Liposarcoma of the Spermatic Cord: Institutional Experience and Pooled Analysis

BACKGROUND

Liposarcoma of the spermatic cord is rare and frequently misdiagnosed. The standard therapeutic approach has been radical inguinal orchiectomy with wide local resection of surrounding soft tissues. The current trend of organ preservation in the treatment of several cancers has started to evolve. Herein we present our testis-sparing surgery experience in the treatment of spermatic cord liposarcoma and a pooled analysis on this topic.

MATERIALS AND METHODS

Clinical information from patient receiving organ-sparing surgery was described. Clinical studies evaluating this issue were identified by using a predefined search strategy, e.g., Pubmed database with no restriction on date of published papers. The literature search used the following terms: epidemiology , surgery , chemotherapy , radiotherapy , testis sparing surgery, spermatic cord sarcomas/ liposarcomas.

RESULTS

Patient received a complete excision of the lesion, preserving the spermatic cord and the testis. The final pathological report showed a well differentiated liposarcoma with negative surgical margins and no signs of local invasion. After 2-year of follow-up, there was no evidence of local recurrence. Since the first case reported in 1952, a total of about 200 well-documented spermatic cord liposarcoma cases have been published in English literature. Among these patients, only three instances were reported to have received an organ-sparing surgery in the treatment of spermatic cord liposarcoma.

CONCLUSIONS

Radical inguinal orchiectomy and resection of the tumor with a negative microscopic margin is the recommended treatment for liposarcoma of the spermatic cord. But for small, especially well-differentiated, lesions, testis-sparing surgery might be a good option if an adequate negative surgical margin is assured.