Deep learning radiomics-based prediction model of metachronous distant metastasis following curative resection for retroperitoneal leiomyosarcoma: a bicentric study.

BACKGROUND: Combining conventional radiomics models with deep learning features can result in superior performance in predicting the prognosis of patients with tumors; however, this approach has never been evaluated for the prediction of metachronous distant metastasis (MDM) among patients with retroperitoneal leiomyosarcoma (RLS). Thus, the purpose of this study was to develop and validate a preoperative contrast-enhanced computed tomography (CECT)-based deep learning radiomics model for predicting the occurrence of MDM in patients with RLS undergoing complete surgical resection. METHODS: A total of 179 patients who had undergone surgery for the treatment of histologically confirmed RLS were retrospectively recruited from two tertiary sarcoma centers. Semantic segmentation features derived from a convolutional neural network deep learning model as well as conventional hand-crafted radiomics features were extracted from preoperative three-phase CECT images to quantify the sarcoma phenotypes. A conventional radiomics signature (RS) and a deep learning radiomics signature (DLRS) that incorporated hand-crafted radiomics and deep learning features were developed to predict the risk of MDM. Additionally, a deep learning radiomics nomogram (DLRN) was established to evaluate the incremental prognostic significance of the DLRS in combination with clinico-radiological predictors. RESULTS: The comparison of the area under the curve (AUC) values in the external validation set, as determined by the DeLong test, demonstrated that the integrated DLRN, DLRS, and RS models all exhibited superior predictive performance compared with that of the clinical model (AUC 0.786 [95% confidence interval 0.649-0.923] vs. 0.822 [0.692-0.952] vs. 0.733 [0.573-0.892] vs. 0.511 [0.359-0.662]; both P < 0.05). The decision curve analyses graphically indicated that utilizing the DLRN for risk stratification provided greater net benefits than those achieved using the DLRS, RS and clinical models. Good alignment with the calibration curve indicated that the DLRN also exhibited good performance. CONCLUSIONS: The novel CECT-based DLRN developed in this study demonstrated promising performance in the preoperative prediction of the risk of MDM following curative resection in patients with RLS. The DLRN, which outperformed the other three models, could provide valuable information for predicting surgical efficacy and tailoring individualized treatment plans in this patient population. TRIAL REGISTRATION: Not applicable.

Case report: Highly response to low-dose brachytherapy in recurrent retroperitoneal leiomyosarcoma with FANCD2 frameshift mutation: a unique case study.

We report a case of recurrent retroperitoneal leiomyosarcoma in a male who achieved a rapid and robust but transient clinical response to low-dose iodine-125 brachytherapy. A FANCD2 frameshift mutation was detected by gene sequencing in the cancerous tissue.

Nomogram predicting overall survival after surgical resection for retroperitoneal leiomyosarcoma patients.

Background: Surgery is the best way to cure the retroperitoneal leiomyosarcoma (RLMS), and there is currently no prediction model on RLMS after surgical resection. The objective of this study was to develop a nomogram to predict the overall survival (OS) of patients with RLMS after surgical resection. Methods: Patients who underwent surgical resection from September 2010 to December 2020 were included. The nomogram was constructed based on the COX regression model, and the discrimination was assessed using the concordance index. The predicted OS and actual OS were evaluated with the assistance of calibration plots. Results: 118 patients were included. The median OS for all patients was 47.8 (95% confidence interval (CI), 35.9-59.7) months. Most tumor were completely resected (n=106, 89.8%). The proportions of French National Federation of Comprehensive Cancer Centres (FNCLCC) classification were equal as grade 1, grade 2, and grade 3 (31.4%, 30.5%, and 38.1%, respectively). The tumor diameter of 73.7% (n=85) patients was greater than 5 cm, the lesions of 23.7% (n=28) were multifocal, and 55.1% (n=65) patients had more than one organ resected. The OS nomogram was constructed based on the number of resected organs, tumor diameter, FNCLCC grade, and multifocal lesions. The concordance index of the nomogram was 0.779 (95% CI, 0.659-0.898), the predicted OS and actual OS were in good fitness in calibration curves. Conclusion: The nomogram prediction model established in this study is helpful for postoperative consultation and the selection of patients for clinical trial enrollment.

Ureteral reconstruction with appendiceal interposition graft following resection of retroperitoneal leiomyosarcoma.

Ureteral defects can be repaired using a variety of different techniques that depend on the length and position of the defect. Here we describe a case where a long, upper-ureteral defect was successfully reconstructed using an appendiceal interposition graft. A 60-year-old female patient underwent resection of a right-sided retroperitoneal leiomyosarcoma that was encasing the entire upper ureter and obstructing the right kidney. The mass was resected en bloc, leaving behind an 11 cm ureteral defect. The defect was successfully reconstructed with an appendiceal interposition graft. Appendiceal interposition grafts are a feasible and effective approach for ureteral reconstruction in adults following oncologic resection. We describe various technical aspects that optimize the success of ureteral reconstruction.

A competing risk-based nomogram to predict cancer-specific survival in patients with retroperitoneal leiomyosarcoma.

Considering the rarity and aggressive nature of retroperitoneal leiomyosarcoma (RLMS), several prognostic factors might contribute to the cancer-specific mortality of these patients. This study aimed to construct a competing risk-based nomogram to predict cancer-specific survival (CSS) for patients with RLMS. In total, 788 cases from the Surveillance, Epidemiology, and End Results (SEER) database (2000-2015) were included. Based on the Fine & Gray's method, independent predictors were screened to develop a nomogram for predicting 1-, 3-, and 5-year CSS. After multivariate analysis, CSS was found significantly associated with tumor characteristics (tumor grade, size, range), as well as surgery status. The nomogram showed solid prediction power and was well calibrated. Through decision curve analysis (DCA), a favorable clinical utility of the nomogram was demonstrated. Additionally, a risk stratification system was developed and distinctive survival between risk groups was observed. In summary, this nomogram showed a better performance than the AJCC 8th staging system and can assist in the clinical management of RLMS.

A century of retroperitoneal soft-tissue sarcoma research: From single center experience to precision oncology? A bibliometric analysis of past, present, and future perspectives.

BACKGROUND: Increasing publication numbers in the biomedical field led to an improvement of patient care in many aspects but are challenging for scientists when integratively processing data of their fields. Using bibliometric analyses, the present study assesses the productivity and predominant topics in retroperitoneal soft-tissue sarcoma (RPS) research across the past 122 years, thereby identifying crucial questions to address in future RPS research. METHODS: Using the Web of Science Core Collection, 1018 RPS-associated publications from 1900 to 2022 were identified and analyzed regarding key bibliometric variables using the Bibliometrix R package and the VOSviewer software. RESULTS: A continuous increase in RPS-associated publication numbers can be noticed over the time, which is strongly pronounced from 2005 onwards, and is characterized by a multinationally driven collaborative clinical research focus. The research primarily reflects progression regarding surgical techniques, histology-based therapy, radiotherapy regimens, and identification of prognostic clinicopathological factors. This progression is accompanied with improved overall survival of RPS patients. However, a paucity of RPS-specific basic/translational research indicates that such research might be additionally needed to better understand the pathophysiology of RPS and with that to enable the development of personalized therapies and to further improve patient outcome. CONCLUSION: Increasing publication numbers of multinationally driven clinical RPS research are accompanied with improved overall survival of RPS patients, highlighting the importance of international collaborations to facilitate future clinical trials. However, this bibliometric analysis reveals a lack of RPS-specific basic/translational research which is needed to further improve patient outcome in the context of precision oncology.

Keeping up the 'race pace' in a patient with nonuterine leiomyosarcoma.

The most common site of involvement of leiomyosarcoma is the retroperitoneum, accounting for approximately 50% of all cases. The case study presented herein describes the journey of a man with a grade 2 retroperitoneal leiomyosarcoma at the time of diagnosis. The patient received first-line doxorubicin (six cycles) and evofosfamide (11 cycles) during participation in the phase III, randomized, double-blind SARC021 trial and achieved stable disease. Upon progression, he received 24 cycles of second-line trabectedin with stable disease, then third-line pazopanib for 14 months with stable disease. Finally, he received fourth-line gemcitabine monotherapy for 5 months until disease progression, which was followed by death. Notably, trabectedin provided long-term disease control and maintained the patient's functional performance throughout treatment.

Long-term survival by repeat resection for metastases from primary retroperitoneal leiomyosarcoma: A case report.

BACKGOUND: Retroperitoneal (RP) leiomyosarcoma (LMS) is a rare type of cancer, accounting for 0.1% of all malignancies. The gold-standard treatment for sarcoma is complete resection, and a 50% 5-year overall survival (OS) rate can be achieved by curative surgery. The survival benefits of radiotherapy and systemic chemotherapy for recurrence are not as good as those of surgical resection. To the best of our knowledge, there are a few reports that aggressive radical surgery significantly prolonged the survival period as our case. This case was reported in accordance with the SCARE 2020 Guideline (Ref). CASE PRESENTATION: An 84-year-old woman was referred to our hospital for treatment of a primary RP tumour. At the age of 52-year-old, she underwent complete resection of an RP mass in 1991. Twenty-four years after the primary resection, metachronous recurrences occurred within the soft tissues, which were repeatedly resected. From 2015-2019, liver resections were performed thrice, and the patient survived with no signs of recurrence 1 year after the last surgery. CONCLUSION: Long-term survival of 29 years was achieved after undergoing over 20 surgical resections. Herein, we report the long-term survival of a patient who underwent repeated aggressive surgical resections for RP LMS recurrence anda literature review.

Granulocyte colony-stimulating factor producing retroperitoneal leiomyosarcoma.

INTRODUCTION: Granulocyte colony-stimulating factor-producing nonhematopoietic malignancies have poor clinical outcomes. CASE PRESENTATION: A 62-year-old woman complaining of fever and left lower quadrant pain was referred to our hospital. A left retroperitoneal tumor was suspected on computed tomography, and laboratory data showed leukocytosis and markedly elevated granulocyte colony-stimulating factor. She underwent left nephroureterectomy, partial colectomy, and psoas muscle resection. The histological examination showed a granulocyte colony-stimulating factor-producing retroperitoneal leiomyosarcoma. Three months after the operation, she developed lung and liver metastases and received the chemotherapy, including doxorubicin and ifosfamide. Eight months after the operation, these lesions had progressed, and a new bone metastasis appeared. Twelve months after the operation, she received pazopanib and radiation for bone metastases. However, the metastases progressed, and she died 17 months after the operation. CONCLUSION: Since granulocyte colony-stimulating factor-producing retroperitoneal leiomyosarcoma had a very poor prognosis irrespective of intensive treatment including wide resection, effective systemic therapy should be required.

125I brachytherapy seeds implantation for an inoperable large retroperitoneal leiomyosarcoma.

Retroperitoneal leiomyosarcoma is relatively uncommon. Leiomyosarcoma has accounted for about 5%-10% of soft-tissue sarcoma, and 1/2-2/3 of the primary lesions were retroperitoneal, with a cumulative 5-year survival rate of only 35%.Leiomyosarcoma is one kind of soft-tissue sarcoma with the lowest survival rates due to the invasive growth, difficult treatment, and poor prognosis.The present study reported a case of a 78-year-old male diagnosed as left retroperitoneal leiomyosarcoma, who had received three operations. Computed tomography (CT) demonstrated a mass of approximately 12.9 cm × 6.9 cm × 6.6 cm in his retroperitoneal region. The Eastern cooperative oncology group and numerical rating scale scores of pain were 1 and 5, respectively. Multiple treatment strategies were administered, including the application of drainage and125I seed implantation. A total of 90125I seeds were implanted into the tumor through repetitious operations, with 30 seeds each time. Treatment planning system was involved to calculate the source distribution.125I seeds with the activity of 0.5 mCi were implanted under the guidance of CT, and dosimetric verification was performed after the operation. D90 (90% minimum prescription dose received by target volume) was 40 Gy. Follow-up was performed after 6 months, and complete response was achieved in the local lesions. However, there was no evidence-based treatment currently and the majority of our knowledge was based on results from case reports, thus further studies would be required.

CT imaging improves histopathological grading of retroperitoneal leiomyosarcomas.

BACKGROUND: Initial grading of retroperitoneal leiomyosarcoma (LMS) is performed by core biopsy (CB) however, discrepancy between grade of tumour at initial CB and surgical excision is recognised, raising concerns about the accuracy of CB for directing neoadjuvant therapy. The histological grading system used for staging LMS consists of 3 components: tumour differentiation, mitotic index and proportion of necrosis. We postulate that assessment of necrosis by histopathology alone is inadequate, resulting in under-grading of LMS. We propose and assess a combined grading system that incorporates CT scan findings into pre-surgical grading. METHODS: Retrospective, blinded review of CT, CB histology and final surgical histology of patients with retroperitoneal LMS was undertaken. A modified grading system, CTH-Grade, was derived by replacing the CB necrosis score with a CT-derived necrosis score. The sensitivity and specificity of CTH-Grade, the standard histopathology scoring, H-grade were compared. Inter-observer variability in assessment of CT necrosis was also assessed. RESULTS: 53 patients fulfilled criteria for inclusion. CT was more sensitive at detection of necrosis than CB histology alone with sensitivity of 100% vs 53%. The use of CTHGrade resulted in increased detection of high-grade tumours with CTH-grade having sensitivities of 80% and 35% for Grade 2 and 3 tumours respectively vs 53% and 15% with H-Grade. Assessment of reader agreement demonstrated Kappa scores of 0.8. CONCLUSION: Histology from CB under-grades LMS due to undersampling of tumour necrosis. CT is more sensitive in assessing necrosis and its incorporation into a modified CT-histopathology grading system (CTH-Grade) improves accuracy of grading with significant implications for patient management.

Robotic resection of a giant retroperitoneal leiomyosarcoma: A case report.

The management of abdominal leiomyosarcoma is challenging. Surgical excision is considered the only effective treatment; however, this is associated with considerable morbidity. Robotic surgery has emerged during the past decades and has enhanced the general surgery armamentarium, allowing surgeons to carry out demanding operations in a safe manner. The surgical resection of retroperitoneal leiomyosarcoma (RPLM) can be associated with significant morbidity, which is primarily due to the origin or the close proximity of the tumor with important vascular structures, including the inferior vena cava and tributaries, the duodenum and the ureter. The present case describes the first case of robotic resection of RPLM in a high-volume robotic center. In the present case, a large RPLM was safely removed with respect to oncological principles with the use of the Da Vinci platform.

Prognostic factors in patients with recurrent or metastatic retroperitoneal leiomyosarcoma.

AIMS: Factors that predict the prognosis of patients with recurrent or metastatic retroperitoneal leiomyosarcomas after treatment are uncertain. MATERIALS & METHODS: Clinical and pathological data on 22 patients with retroperitoneal leiomyosarcomas who were treated by a multidisciplinary abdominal soft-tissue tumor group were analyzed retrospectively to identify prognostic factors for their progression-free survival (PFS). RESULTS & CONCLUSION: The median PFS in the 22 patients was 9 months. Microvessel density in tumor tissues, which was evaluated via CD34 expression in 16 cases, and the presence of metastasis on admission were both found to be correlated with PFS in a Kaplan-Meier analysis, but not in a multivariate analysis. The multivariate analysis did, however, show that complete resection of tumors and the FNCLCC (Fédération Nationale des Centres de Lutte Contre Le Cancer) disease grade were independent factors predicting PFS.