Comprehensive Review of Abdominopelvic Mesenchymal Tumors with Radiologic Pathologic Correlation and Update on Current Treatment Guidelines - Part 1

Rapid and Precise Diagnosis of Retroperitoneal Liposarcoma with Deep-Learned Label-Free Molecular Microscopy

The retroperitoneal liposarcoma (RLPS) is a rare malignancy whose only curative therapy is surgical resection. However, well-differentiated liposarcomas (WDLPSs), one of its most common types, can hardly be distinguished from normal fat during operation without an effective margin assessment method, jeopardizing the prognosis severely with a high recurrence risk. Here, we combined dual label-free nonlinear optical modalities, stimulated Raman scattering (SRS) microscopy and second harmonic generation (SHG) microscopy, to image two predominant tissue biomolecules, lipids and collagen fibers, in 35 RLPSs and 34 normal fat samples collected from 35 patients. The produced dual-modal tissue images were used for RLPS diagnosis based on deep learning. Dramatically decreasing lipids and increasing collagen fibers during tumor progression were reflected. A ResNeXt101-based model achieved 94.7% overall accuracy and 0.987 mean area under the ROC curve (AUC) in differentiating among normal fat, WDLPSs, and dedifferentiated liposarcomas (DDLPSs). In particular, WDLPSs were detected with 94.1% precision and 84.6% sensitivity superior to existing methods. The ablation experiment showed that such performance was attributed to both SRS and SHG microscopies, which increased the sensitivity of recognizing WDLPS by 16.0 and 3.6%, respectively. Furthermore, we utilized this model on RLPS margins to identify the tumor infiltration. Our method holds great potential for accurate intraoperative liposarcoma detection.

Tailored Physical Therapy in a Case of Tenotomy Post Hip Flexion Deformity With Structural Scoliosis: A Case Report

Retroperitoneal tumours, mainly classified as malignant and benign, have a rare incidence. It includes major parts of the peritoneum, and surgical excision remains the optimal pathway to remove the tumour. As with any surgery, tumour resection comes with its own complications. These complications would manifest differently depending on patient adaptation or compensation for these drawbacks. Physiotherapy and its positive effects as a need after any surgical procedure become a boon when implemented as and when required. The present study describes the case of a 32-year-old woman who has complained of pain in her right hip for one year, along with forward-bending walking and difficulty sitting. The patient had a history of retroperitoneal tumour excision, after which, to compensate for the pain, she started walking by bending forward, which developed into a hip flexion deformity. The patient was managed by tenotomy and was referred to a physiotherapy outpatient (OPD) for further management. Our aim was to improve overall mobility through gait training and prevent relapses of the contracture.

Adult omental alveolar rhabdomyosarcoma: An unusual site. A case report and literature review

Introduction and importance

Omental alveolar rhabdomyosarcoma (ARMS) in adults is a rare tumor and is not a common presentation of abdominal pain. We aim to report the eighth case of omental ARMS and perform a review of all publications that pertains to this topic.

Case presentation

we show a case of a Mediterranean 52 year old smoker male, complaining of unbearable dull pain in the right iliac fossa. He had no relevant medical history other than general abdominal pain in the past several months.

Clinical Discussion

the chief complaint was abdominal pain mimicking appendicitis. Physical examination showed a palpable mass in that region. Ultrasound and CT scan revealed a mass arising from the omentum. At this point we excluded the diagnosis of appendicitis and a laparotomy with biopsies sampling had been performed. The microscopical examination led to the diagnosis of alveolar rhabdomyosarcoma (ARMS). Treatment involved multidisciplinary care but the patient died during chemotherapy.

Conclusion

Adult rhabdomyosarcomas (RMS) are rare tumors that can arise from any soft tissue including omentum and should be taken into consideration when dealing with primary tumors that originate from the omental area. The studies and our understanding for this neoplasm are still very limited and should be expanded widely.

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Omental tumors are rare and have a wide range of DDx.

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Omental tumors can present as acute abdominal cases.

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Rhabdomyosarcoma can originate from any mesenchymal tissue and has genetic pathophysiology.

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Adult rhabdomyosarcomas are treated the same way as for its pediatrics' counterpart; although the prognosis is poorer.

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Adult Rhabdomyosarcoma's risk factors have not been studied at all.

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.