Leiomyosarcoma: Current Clinical Management and Future Horizons

Leiomyosarcoma Therapeutic Approaches and Future Directions

Leiomyosarcomas (LMS) are mesenchymal malignancies with smooth muscle differentiation that most commonly arise in the uterus, retroperitoneum, and extremity. Clinical course is variable, and management differs by site of origin. Recently completed and ongoing clinical trials are optimizing LMS management, and multidisciplinary care by an expert team is essential to navigate the nuances and provide optimal care. Advances in molecular characterization have improved diagnosis and identification of novel prognostic factors and systemic therapies. This article provides an overview of LMS presentation, diagnosis, molecular features, and clinical management, and highlights advancements in LMS biology and treatment.

CT-based quantification of intratumoral heterogeneity for predicting distant metastasis in retroperitoneal sarcoma

OBJECTIVES

Retroperitoneal sarcoma (RPS) is highly heterogeneous, leading to different risks of distant metastasis (DM) among patients with the same clinical stage. This study aims to develop a quantitative method for assessing intratumoral heterogeneity (ITH) using preoperative contrast-enhanced CT (CECT) scans and evaluate its ability to predict DM risk.

METHODS

We conducted a retrospective analysis of 274 PRS patients who underwent complete surgical resection and were monitored for ≥ 36 months at two centers. Conventional radiomics (C-radiomics), ITH radiomics, and deep-learning (DL) features were extracted from the preoperative CECT scans and developed single-modality models. Clinical indicators and high-throughput CECT features were integrated to develop a combined model for predicting DM. The performance of the models was evaluated by measuring the receiver operating characteristic curve and Harrell's concordance index (C-index). Distant metastasis-free survival (DMFS) was also predicted to further assess survival benefits.

RESULTS

The ITH model demonstrated satisfactory predictive capability for DM in internal and external validation cohorts (AUC: 0.735, 0.765; C-index: 0.691, 0.729). The combined model that combined clinicoradiological variables, ITH-score, and DL-score achieved the best predictive performance in internal and external validation cohorts (AUC: 0.864, 0.801; C-index: 0.770, 0.752), successfully stratified patients into high- and low-risk groups for DM (p < 0.05).

CONCLUSIONS

The combined model demonstrated promising potential for accurately predicting the DM risk and stratifying the DMFS risk in RPS patients undergoing complete surgical resection, providing a valuable tool for guiding treatment decisions and follow-up strategies.

CRITICAL RELEVANCE STATEMENT

The intratumoral heterogeneity analysis facilitates the identification of high-risk retroperitoneal sarcoma patients prone to distant metastasis and poor prognoses, enabling the selection of candidates for more aggressive surgical and post-surgical interventions.

KEY POINTS

Preoperative identification of retroperitoneal sarcoma (RPS) with a high potential for distant metastasis (DM) is crucial for targeted interventional strategies. Quantitative assessment of intratumoral heterogeneity achieved reasonable performance for predicting DM. The integrated model combining clinicoradiological variables, ITH radiomics, and deep-learning features effectively predicted distant metastasis-free survival.

Retrospective Analysis of BRCA-Altered Uterine Sarcoma Treated With Poly(ADP-ribose) Polymerase Inhibitors

PURPOSE

Uterine sarcomas are rare, aggressive tumors with limited chemotherapy responsiveness. Poly(ADP-ribose) polymerase inhibitors (PARPis) have emerged as targeted therapies for patients with BRCA mutations across multiple cancer types, with anecdotal responses in uterine sarcoma. This retrospective, single-center study aims to describe relevant genomic and clinical features of patients with BRCA-altered uterine sarcoma and the efficacy of PARPis in this population.

METHODS

Eligible patients included all histopathologically confirmed uterine sarcoma with pathogenic BRCA alterations identified through Memorial Sloan Kettering Cancer Center-integrated mutation profiling of actionable cancer targets, excluding carcinosarcoma. Genomic, pathologic, and treatment information was extracted from the cBioPortal database and chart review.

RESULTS

Thirty-five patients were identified with uterine sarcoma harboring pathogenic BRCA alterations, including 33 BRCA2 alterations (70% homozygous deletions, 3% structural variants, 27% mutations) and two BRCA1 mutations. Leiomyosarcoma (LMS) was the most common histology (86%). Thirteen patients with uterine LMS were treated with PARPis in the recurrent/metastatic therapy setting (54% combination therapy regimens) with an overall response rate (ORR) of 46% (1 of 6 for PARPi monotherapy, 5 of 7 for PARPi combination regimens), a clinical benefit rate (CBR) of 62%, and a median progression-free survival (PFS) of 13.2 months (range, 1.0-71.9). The median PFS ratio compared with previous systemic therapy was 1.9 (range, 0.4-53.9), and 58% had a PFS ratio of ≥1.3. The median time on PARPi was 14.5 months (range, 1.3-71.9). The ORR for patients with somatic BRCA2 deletions was 60% (n = 6 of 10), with a CBR of 80% (n = 8 of 10). One patient with metastatic disease and progression on previous hormonal and chemotherapy demonstrated a complete response to PARP/PD-L1 inhibitor combination therapy, ongoing for 70+ months.

CONCLUSION

PARPis demonstrate promising efficacy in patients with uterine LMS with somatic BRCA2 deletions.

Efficacy of immune checkpoint inhibitors in the treatment of soft tissue sarcoma: A systematic review and meta-analysis of clinical trials

BACKGROUND

Soft tissue sarcomas (STS) are a heterogeneous group of tumors with diverse clinical and molecular characteristics, characterized by limited treatment options and poor prognosis. Immune checkpoint inhibitors (ICIs) have emerged as promising therapies for STS, yet comprehensive evaluations of their efficacy, especially in combination with other treatments, are scarce.

METHODS

We conducted a systematic review and meta-analysis of clinical trials on ICIs in STS treatment, sourced from PubMed, Embase, and the Cochrane Central Register of Controlled Trials up to May 31, 2024. The studies included both monotherapy and combination therapies with ICIs. We assessed the methodological quality using the Cochrane Risk of Bias 2 tool and the Methodological Index for Non-Randomized Studies. Data synthesis involved random-effects meta-analysis to determine pooled proportions and 95% confidence intervals (CIs) for objective response rates (ORR), disease control rates (DCR), and high-grade treatment-related adverse events (TRAEs).

RESULTS

The analysis included 38 studies with 1349 patients covering 24 STS subtypes. The overall ORR was 16% (95% CI 0.12-0.21), DCR was 64% (95% CI 0.57-0.70), and the rate of Grade 3-5 TRAEs was 19% (95% CI 0.13-0.27). Treatments combining ICIs with tyrosine kinase inhibitors (TKIs) showed the highest efficacy (ORR 28%, 95% CI 0.18-0.40), albeit with increased adverse events. ORRs in first-line treatments were substantially higher (28%) compared to second-line treatments or beyond (11%). Subtypes like alveolar soft part sarcoma (ASPS), angiosarcoma (AS), and epithelioid sarcoma (ES) exhibited favorable responses exceeding 30%.

CONCLUSIONS

This systematic review and meta-analysis indicate that ICIs, particularly when combined with TKIs, provide substantial therapeutic benefits in treating STS, significantly enhancing response rates in specific subtypes such as ASPS and AS. The results underscore the transformative potential of ICIs in STS treatment strategies. However, the variability across subtypes and treatment lines emphasizes the need for further randomized controlled trials to refine and personalize therapeutic approaches, ensuring optimal outcomes for patients with these diverse malignancies.

Statistics of Visceral Sarcoma in Japan: Report From the Population-Based National Cancer Registry (NCR) in Japan

BACKGROUND AND OBJECTIVES

Sarcomas developing in the visceral organs are extremely rare, with no previous reports to describe their national epidemiology. We analyzed Japanese domestic statistics for visceral sarcoma, using the National Cancer Registry (NCR) in Japan, a population-based database launched in 2016.

METHODS

We identified 3245 cases of visceral sarcomas in the NCR dated 2016-2019 to analyze demographic and disease information, initial diagnostic process, volume and type of the hospitals, treatment, and prognosis.

RESULTS

Visceral sarcoma shows a higher prevalence in the older generation (60+ years), with a significant male predominance (p = 0.006). Leiomyosarcomas occurred frequently in the gastrointestinal tract (N = 240; 39.5%), and angiosarcomas in the liver, gall bladder, pancreas, and spleen (N = 244; 43.9%). Visceral sarcomas were often treated in facilities of lower volume without specific adjuvant treatments (p < 0.001). The cumulative 3-year overall survival was 44.8%, and several factors such as surgery or absence of chemotherapy positively affected survival.

CONCLUSIONS

This is the first nationwide study in Japan to analyze the inclusive epidemiology of visceral sarcomas. Visceral sarcomas are characterized by senior and male predominance with relatively poor prognosis, often managed in nonspecialized facilities and rarely with adjuvant therapies. Several histologic subtypes had the propensity to develop in specific organs.

Primary Omental Leiomyosarcoma With Pulmonary Metastases: A Case Report of Surgical Management and Chemotherapy Response

Primary omental leiomyosarcoma is an extraordinarily rare tumor, with only a limited number of cases reported in the medical literature. Early surgical intervention appears to be a key determinant in the successful treatment of this malignancy, although more cases are needed to establish a standardized approach for optimal management. Leiomyosarcomas originating from the omentum present unique diagnostic challenges due to their rarity and often nonspecific clinical and radiologic findings. The complexities of diagnosing and managing this condition are compounded in rural areas where access to advanced diagnostic tools and specialists is limited. Leiomyosarcomas appear on abdominal computerized tomography (CT) as heterogeneous solid masses with cystic areas that enhance with contrast. While imaging can suggest the diagnosis, histopathology is required for confirmation. These tumors are highly aggressive, and complete surgical resection is the only definitive treatment, with resectability depending on peritoneal implants or metastasis. Other treatments, such as chemotherapy, radiation, and embolization, have variable success. Liver metastasis is the most common and a poor prognostic factor. Despite alternative therapies, surgery remains the best option for long-term survival. This case not only highlights the rarity and diagnostic challenges of omental leiomyosarcoma but also underscores the importance of timely referral to specialized centers. It further emphasizes the need for comprehensive diagnostic evaluations and personalized treatment plans tailored to the unique characteristics of each patient. Addressing these challenges through early intervention and targeted therapies is crucial to improving outcomes for patients with rare malignancies like omental leiomyosarcoma.

Uterine leiomyosarcoma as a rare cause of fatal retroperitoneal haemorrhage due to compression and rupture of the renal vein

Abnormal uterine bleeding (AUB) can be caused by uterine tumors, both benign and malignant, although they rarely lead to fatal vascular complications. We present a case of a woman found dead in her home, in which the autopsy highlighted a massive retroperitoneal haemorrhage extending to the left renal lodge and a voluminous uterine tumor of stony consistency and exophytic growth weighing 2250g. The histopathological examination identified the mass as a leiomyosarcoma and demonstrated the presence of a dilation with rupture of the left renal vein, in the absence of neoplastic cells infiltrating the vascular wall. On these findings, it was concluded that the neoplastic mass had caused external compression of the left renal vein, leading to its rupture and to a fatal retroperitoneal haemorrhage. The case was considered of interest as it involved a peculiar etiopathogenetic mechanism causing a lethal complication from uterine leiomyosarcoma which has not yet been reported in the literature.

Clinical and radiologic features of soft tissue sarcoma in trunk and extremities that underwent unplanned excision

BACKGROUND

To identify the clinical and imaging characteristics of soft tissue sarcomas (STS) of the trunk and extremities that undergo unplanned excision.

METHODS

This retrospective study evaluated the data of patients with STS in the trunk or extremities between January 2008 and December 2021. Patients were divided into unplanned and planned excision groups based on their initial treatment. The distribution of histologic subtypes was analyzed, and the magnetic resonance imaging features were evaluated. Multivariable logistic regression was performed to identify variables independently associated with unplanned excision.

RESULTS

A total of 305 patients (mean age±standard deviation, 51±16.4 years; 179 males) were analyzed. The most prevalent subtype in the unplanned excision group was myxofibrosarcoma (22.3%). The unplanned excision group had a significantly smaller tumor size (p < 0.001) and more frequent superficial (p < 0.001) locations. Lobulated shape and peritumoral abnormalities were present in 70.0% and 50.0% of the unplanned excision group, respectively. Tumor size (adjusted odds ratio [OR], 0.87 per 1 cm increase; 95% confidence interval [CI], 0.77-0.98; p = 0.025) and superficial location (adjusted OR, 3.48; 95% CI, 1.57-7.72; p = 0.002) were independently associated with unplanned excision.

CONCLUSION

Myxofibrosarcoma is associated with a high frequency of unplanned excision. A significant number of patients in the unplanned excision group demonstrated a lobulated shape and peritumoral abnormalities. Only small tumor size and superficial location were independently associated with unplanned STS excision.

Development and external validation of a machine learning model for prediction of survival in extremity leiomyosarcoma

PURPOSE

Machine learning (ML) models have been used to predict cancer survival in several sarcoma subtypes. However, none have investigated extremity leiomyosarcoma (LMS). ML is a powerful tool that has the potential to better prognosticate extremity LMS.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was queried for cases of histologic extremity LMS (n = 634). Patient, tumor, and treatment characteristics were recorded, and ML models were developed to predict 1-, 3-, and 5-year survival. The best performing ML model was externally validated using an institutional cohort of extremity LMS patients (n = 46).

RESULTS

All ML models performed best at the 1-year time point and worst at the 5-year time point. On internal validation within the SEER cohort, the best models had c-statistics of 0.75-0.76 at the 5-year time point. The Random Forest (RF) model was the best performing model and used for external validation. This model also performed best at 1-year and worst at 5-year on external validation with c-statistics of 0.90 and 0.87, respectively. The RF model was well calibrated on external validation. This model has been made publicly available at https://rachar.shinyapps.io/lms_app/ CONCLUSIONS: ML models had excellent performance for survival prediction of extremity LMS. Future studies incorporating a larger institutional cohort may be needed to further validate the ML model for LMS prognostication.

Extent of macroscopic vascular invasion predicts distant metastasis in primary leiomyosarcoma of the inferior vena cava

BACKGROUND

In retroperitoneal leiomyosarcoma (RP LMS), the predominant issue is distant metastasis (DM). We sought to determine variables associated with this outcome and disease-specific death (DSD).

METHODS

Data were retrospectively collected on patients with primary RP LMS treated at a high-volume center from 2002 to 2023. For inferior vena cava (IVC)-origin tumors, the extent of macroscopic vascular invasion was re-assessed on each resection specimen and correlated with preoperative cross-sectional imaging. Crude cumulative incidences were estimated for DM and DSD and univariable and multivariable models were performed.

RESULTS

Among 157 study patients, median tumor size was 11.0 cm and 96.2% of cases were intermediate or high grade. All patients underwent complete resection, 56.7% received chemotherapy (43.9% neoadjuvant) and 14.6% received radiation therapy. Only tumor size and grade and not site of tumor origin (e.g., IVC vs. other) were associated with DM and DSD (p < 0.05). Among 64 patients with IVC-origin tumors, a novel 3-tier classification was devised based on the level of intimal disruption, which was associated with both DM (p = 0.007) and DSD (0.002).

CONCLUSION

In primary RP LMS, only tumor size and grade are predictive of DM and DSD. In IVC-origin tumors, the extent of macroscopic vascular invasion is also strongly predictive of these outcomes.

Sarcopenia Is Associated with Neoplasm of Bone and Articular Cartilage: Findings from Mendelian Randomized Study

Exploring the causal relationship between sarcopenia and neoplasm of bone and articular cartilage (NBAC) by bidirectional Mendelian randomization (MR). Genome-wide association study (GWAS) data on sarcopenia-associated traits including appendicular lean mass, low handgrip strength (including criteria from the European Working Group on Sarcopenia in Older People and the Foundation for the National Institutes of Health), and usual walking speeds were obtained from the UK Biobank. GWAS data for NBAC (benign and malignant) were provided by the Finnish Genetic Database. Three different methods of MR analysis, including inverse-variance weighted, Mendelian randomized Egger regression, and weighted median methods, were utilized. MR analysis showed that high appendicular lean mass was positively associated with the risk of developing benign NBAC (odds ratio and 95% confidence interval = 1.236 (1.026,1.489), p = 0.025). At the same time, there is no statistically significant association was found between traits related to sarcopenia and malignant neoplasm of bone and articular cartilage. There was also no reverse causal correlation between NBAC and traits related to sarcopenia. In European populations, better appendicular lean body mass is positively associated with the risk of benign neoplasm of bone and articular cartilage, representing the possibility that sarcopenia may be a protective factor against neoplasm of bone and articular cartilage.

Doxorubicin and trabectedin for recurrent leiomyosarcoma - A case report

Uterine leiomyosarcoma (LMS) represents a rare yet highly aggressive tumor, comprising approximately 1% of uterine malignancies. First-line regimens involving doxorubicin or gemcitabine and docetaxel demonstrate modest response rates. Notably, the combination of doxorubicin plus trabectedin has emerged as a preferred first-line option following the LMS-04 study, showing superior progression-free survival compared to doxorubicin alone. Second-line therapy for recurrent LMS poses greater challenges, with single-agent treatments exhibiting limited efficacy. Herein, we present a case of a 65-year-old woman with stage 1B uterine leiomyosarcoma, previously treated with surgical resection and adjuvant gemcitabine/docetaxel, due to surgical morcellation. Despite initially achieving disease-free status, she experienced a first recurrence 5 years later, treated with surgery and radiation, and a second recurrence 4 years after, necessitating second-line therapy with doxorubicin and trabectedin. The patient exhibited a remarkable response to this regimen, achieving partial response after 6 cycles of doxorubicin and trabectedin chemotherapy. She maintained stable disease over 13 cycles of maintenance trabectedin and 6 months off treatment, for a total of 16 months of progression-free survival. This case underscores the potential efficacy of combination chemotherapy with doxorubicin and trabectedin as a second-line treatment option for recurrent uterine leiomyosarcoma.

Giant "Hydra Headed" Uterine Fibroid in a Nullipara: A Case Report

Background

Uterine fibroids, or Leiomyoma is a type of Smooth Muscle Tumors of the uterus (SMTs) and are common in the black race. Giant uterine fibroids, on the other hand, are uncommon and may occur during patient dissimulation. Dissimulation may occur because of a dread of surgery and hospitals visits, fear of surgical death, chronic intake of herbal concussion, and a religio-traditional strong belief system on instant healing following prayers, among others. Myths like belief of defecating the uterine fibroids, some herbs that can melt them away, and the belief that such illness may follow ancestral curses can fuel dissimulation. The surgical approach can be a source of challenge, careful case selection considering the size and number of tumors can be helpful.

Case report

We present a 35-year-old nulligravida who presented to the clinic with a 14-year history of progressive abdominal swelling. Examination revealed a firm mass with a symphysio-fundal height of 55 cm. She subsequently had an open abdominal myomectomy with all the myoma nodules weighing 12.9 kg in total! Histology confirmed uterine fibroid.

Conclusion

It is possible to offer open myomectomy in patients with giant uterine fibroid following careful patient selection with a consent for possible hysterectomy. Dissimulation can be minimized with repetitive counseling of patients. The choice of surgery depends on the size and number of uterine fibroids, but surgical approach does not necessarily influence fecundity.

Primary Retrovesical Leiomyosarcoma: A Case Report

Soft tissue sarcomas (STS) are a rare group of malignant tumors in adults. This group of tumors contains a variety of subtypes, each with distinct clinical features and presentations. Leiomyosarcoma is among the most common subtypes, which typically occur within the uterus, retroperitoneum, abdomen, and large blood vessels. At presentation, tumors are often large and may have metastasized to the lungs, liver, or peritoneum. Given the rarity and variability of the disease, a multidisciplinary treatment approach is essential for management, however, further research is needed to develop histologic-specific guidelines and targeted treatments. Here, we present a case of a 69-year-old male who was found to have a large pelvic mass of unknown etiology after presenting to the emergency department with generalized weakness, decreased appetite, and an inability to ambulate. On examination, he was found to have testicular swelling and trace edema of bilateral lower extremities. Labs significant for lactic acidosis and CT chest/abdomen/pelvis showed a large heterogeneously enhancing mass within the pelvis measuring up to 15 cm x 12 cm x 15 cm, of uncertain origin, but highly concerning for malignancy. Biopsy with immunohistochemical stains of the mass revealed a grade 2 leiomyosarcoma. Due to the size and location of the mass, transfer to a tertiary care center was recommended. Computed tomography angiography (CTA) abdomen/pelvis and magnetic resonance imaging (MRI) abdomen/pelvis performed at the tertiary care hospital revealed a 16.6 cm heterogeneously enhancing, necrotic mass within the retrovesical pelvic space and three liver lesions, which were concerning for metastases. Due to the patient's deconditioning and poor functional status, surgical resection and radiation were not offered. The patient expired soon after his code status was changed to comfort care.

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.

Dedifferentiated Leiomyosarcoma of the Uterine Corpus with Heterologous Component: Clinicopathological Analysis of Five Consecutive Cases from a Single Institution and Comprehensive Literature Review

Dedifferentiation is a very rare phenomenon in uterine leiomyosarcoma (LMS). The aim of this study was to comprehensively analyze the clinicopathological characteristics of uterine dedifferentiated LMS (DDLMS). We reviewed electronic medical records and pathology slides from five patients with uterine DDLMS and performed immunostaining. The mean age of the patients was 56 years. Two patients presented with abdominal discomfort, while in three cases the uterine tumors were detected on routine medical examination. The mean size of the tumors was 17.0 cm. Four patients underwent hysterectomy. The initial stages were distributed as IB (2/5), IIIC (2/5), and IVC (1/5). Post-operative concurrent chemoradiation therapy, radiation therapy, and chemotherapy were administered in one, one, and two patients, respectively. Despite post-operative treatment, three patients developed metastatic recurrences in the abdominal and pelvic organs. Recurrence-free survival time ranged between 4 and 30 months. Histologically, the differentiated areas demonstrated the classic morphology of malignant smooth muscle differentiation, whereas the dedifferentiated areas resembled undifferentiated pleomorphic sarcoma and were characterized by large pleomorphic tumor cells admixed with haphazardly arranged atypical cells with marked nuclear pleomorphism. All cases also exhibited heterologous components, including chondrosarcoma (CSA; 3/5) and rhabdomyosarcoma (2/5). In two cases, the heterologous components were initially detected in primary tumors. In three cases, the primary tumors did not exhibit any dedifferentiated or heterologous components. Instead, more than half of the recurrent tumors consisted of heterologous components. Three cases showed a sharp demarcation between the LMS and CSA components, while in two cases the dedifferentiated area imperceptibly merged with the differentiated component. Immunostaining revealed that the dedifferentiated components exhibited a lack of desmin immunoreactivity in three of the four examined cases. A subset of uterine LMS represents various amounts and types of dedifferentiation and heterologous components in both primary and recurrent tumors. Routine recognition of DDLMS and distinction from its mimickers are required for accurate diagnosis and further characterization of these rare tumors.

Doxorubicin combined with Trabectedin in systemic first-line M+/recurrent leiomyosarcoma patients

PURPOSE OF REVIEW

Currently, the only systemic therapy approved for advanced leiomyosarcoma is Doxorubicin-based monotherapy. Despite disappointing progression-free survival (PFS) and overall survival (OS), no combination therapy has formally ever proven to be more effective. In this clinical setting, selecting the most efficient therapy is key, as most patients become quickly symptomatic with poor performance status.This review aims to describe the current emerging role of Doxorubicin and Trabectedin in first-line setting, compared with doxorubicin alone the current standard of treatment.

RECENT FINDINGS

Previous randomized trials focusing on combination therapies (Doxorubicin + ifosfamide, doxorubicin + evofosfamide, doxorubicin + Olaratumab, or Gemcitabine + Docetaxel) never reported positive results on the primary endpoint (OS or PFS). For the first time, the randomized phase III LMS-04 demonstrated that Doxorubicin and Trabectedin have a better PFS and disease control rate (DCR) compared with Doxorubicin, with higher but still manageable toxicities.

SUMMARY

In the first-line setting, the results of this trial were pivotal for numerous reasons; Doxorubicin-Trabectedin is the first combination that has been proven to be more effective in terms of PFS, ORR and trend of OS compared with doxorubicin alone; moreover, it is clear that trials regarding soft tissue sarcoma should strive to be histology-driven.

Giant Soft Tissue Leiomyosarcoma of the Left Lower Extremity: Case Presentation With a Review of the Literature

Leiomyosarcoma (LMS) accounts for approximately 5-10% of soft tissue sarcomas, with an estimated incidence in the United States (US) of less than one case/200,000 persons, more frequent in women than men. Approximately two-thirds of LMSs are retroperitoneal, abdominal, and mediastinal. Localized, soft tissue LMSs represent a lower percentage, with the lower limbs and trunk being the most frequently involved sites. LMSs larger than 5 cm (so-called giants) are even rarer, and to date have been little reported in the literature. In this paper, we present the case of a giant LMS of the left lower limb in a 73-year-old patient, who had a mass for about two years, and who, after the first diagnostic biopsy, underwent limb amputation. Macroscopic and microscopic examinations confirmed the infiltration of the underlying tibial bone. We briefly discuss eight other cases described in the literature with similar size, pointing out that the parameters with the greatest impact on prognosis proved to be size >5 cm and depth of invasion. Due to the rarity of this neoplasm, little has yet been done in relation to the most suitable therapeutic treatment of such patients, and larger case series are mandated in order to be able to conduct broader-spectrum studies.

Complex Vascular Resections for Retroperitoneal Soft Tissue Sarcoma

Retroperitoneal sarcomas (RPSs) are locally aggressive tumors that can compromise major vessels of the retroperitoneum including the inferior vena cava, aorta, or main tributary vessels. Vascular involvement can be secondary to the tumor's infiltrating growth pattern or primary vascular origin. Surgery is still the mainstay for curing this disease, and resection of RPSs may include major vascular resections to secure adequate oncologic results. Our improved knowledge in the tumor biology of RPSs, in conjunction with the growing surgical expertise in both sarcoma and vascular surgical techniques, has allowed for major vascular reconstructions within multi-visceral resections for RPSs with good perioperative results. This complex surgical approach may include the combined work of various surgical subspecialties.

Case report: High-grade endometrial stromal sarcoma with adrenal glands metastases: An unreported site of metastasis

Background

Endometrial stromal sarcoma is a relatively rare malignant tumor that derives from the malignant transformation of primitive uterine mesenchymal cells. It can lead to distant metastases. High-grade endometrial stromal sarcoma is extremely rare. The adrenal glands are an unreported site of metastasis.

Case summary

A 71-year-old woman with a diagnosis of endometrial stromal sarcoma 30 months ago. After receiving treatment with radiotherapy and chemotherapy, the patient was kept asymptomatic during the follow-up until 2 years later, when she complained of dyspnea. Pulmonary and right adrenal gland metastases were detected by ¹⁸F-FDG PET/CT. The right upper lobe mass was diagnosed as a high-grade endometrial stromal sarcoma metastasis after postoperative pathology. Due to the patient's high risk of surgery, as she had many underlying diseases, we performed adequate preoperative preparation. The physical examination revealed that a hard mass was palpable in the right renal area. The right adrenal mass was resected in our hospital. Immunohistochemistry showed ER (-), PR (-), CD10 (+), P16 (+), Ki-67 (50%). The final diagnosis on pathological examination was a high-grade ESS metastatic to the right adrenal gland. The patient continued treatment in other hospitals after surgical resection. After four months of postoperative follow-up, metastasis was detected again during a PET/CT examination at an outside hospital.

Conclusion

Endometrial stromal sarcoma is rare, and the adrenal glands are an unreported site of metastasis. It has no specific clinical symptoms and mainly found for other reasons. The diagnosis still depends on pathology and immunohistochemistry. If there is no relevant past history, it is difficult to exclude a primary adrenal tumor.