Sarcomatoid hepatocellular carcinoma: From clinical features to cancer genome

Treatment and prognostic implications of strong PD-L1 expression in primary hepatic sarcomatoid carcinoma

Primary hepatic sarcomatoid carcinoma (HSC) is an extremely rare and aggressive subtype of primary liver cancer. HSC has uncertain pathogenesis and dismal prognosis with overall survival of only 8.3 months. The molecular alterations of HSC are also not well understood. In this study, the authors describe a patient who presented with a large liver mass. The patient underwent complete surgical resection and histological examination demonstrated HSC, infiltrating the stomach. PD-L1 was strongly positive in the tumor cells. The patient was started on anti-PD-L1 immunotherapy postsurgery and is doing well 15 months after surgical resection. Tumor whole exome sequencing revealed genetic alterations in TP53, NF2 and MAGEC3 genes, indicating their potential role in tumor development.

Genomic analysis of an aggressive hepatic leiomyosarcoma case following treatment for hepatocellular carcinoma

A 70-year-old man undergoing treatment for immunoglobulin G4-related disease developed a liver mass on computed tomography during routine imaging examination. The tumor was located in the hepatic S1/4 region, was 38 mm in size, and showed arterial enhancement on dynamic contrast-enhanced computed tomography. We performed a liver biopsy and diagnosed moderately differentiated hepatocellular carcinoma. The patient underwent proton beam therapy. The tumor remained unchanged but enlarged after 4 years. The patient was diagnosed with hepatocellular carcinoma recurrence and received hepatic arterial chemoembolization. However, 1 year later, the patient developed jaundice, and the liver tumor grew in size. Unfortunately, the patient passed away. Autopsy revealed that the tumor consisted of spindle-shaped cells exhibiting nuclear atypia and a fission pattern and tested positive for α-smooth muscle actin and vimentin. No hepatocellular carcinoma components were observed, and the patient was pathologically diagnosed with hepatic leiomyosarcoma. Next-generation sequencing revealed somatic mutations in CACNA2D4, CTNNB1, DOCK5, IPO8, MTMR1, PABPC5, SEMA6D, and ZFP36L1. Based on the genetic mutation, sarcomatoid hepatocarcinoma was the most likely pathogenesis in this case. This mutation is indicative of the transition from sarcomatoid hepatocarcinoma to hepatic leiomyosarcoma.

Downregulated expression of PBRM1 in sarcomatoid hepatocellular carcinoma

Sarcomatoid hepatocellular carcinoma (SHCC) is a rare and highly lethal subtype of HCC. The present study aimed to explore the unique markers of SHCC using whole gene expression analysis. Subsequently, gene expression analysis was performed using five sarcomatoid and seven carcinomatoid components of seven tissues from patients with SHCC. The results demonstrated a significant downregulation of polybromo 1 (PBRM1) gene expression in the sarcomatoid components. Immunohistochemical staining also indicated a decreased expression of PBRM1 in the sarcomatoid components. Moreover, gene ontology enrichment analysis revealed that most of the 336 differentially expressed genes between the sarcomatoid and carcinomatoid components were involved in functions associated with DNA replication and histone methylation, which was consistent with the loss of function of PBRM1 which encodes Switch/sucrose-non-fermentable chromatin remodeling complex protein. Therefore, the results of the present study suggested that PBRM1 may be a candidate biomarker for the evaluation of SHCC.

Contrast-enhanced ultrasound features of hepatic sarcomatoid carcinoma different from hepatocellular carcinoma

BACKGROUND

Hepatic sarcomatoid carcinoma (HSC) is a rare malignancy of the liver. The ultrasound and clinical features of HSC have not been determined.

OBJECTIVE

To investigate and compare the ultrasound and clinical features of HSC and hepatocellular carcinoma (HCC), and to reveal the valuable features of HSC.

METHODS

The ultrasound features and clinical data of pathologically proven HSC (n = 37) were compared with HCC (n = 92) in a matching ratio of 1:4 using the propensity score (age, gender and tumor size).

RESULTS

The HSC patients were more likely to accompany with clinical symptoms and vascular invasion than HCC patients (40.5% vs 17.4%, 24.3% vs 6.5%, P < 0.05). The size of HSCs was significantly larger than that of HCCs (P < 0.05). The proportion of patients with elevated alpha-fetoprotein was significantly lower in HSC (35.1% vs 54.3%, P < 0.05). On gray-scale ultrasound images, the HSCs were more likely to demonstrate as indistinct margin and irregular shape lesions compared to HCCs (78.4% vs 48.8%; 70.3% vs 23.9%, P < 0.05). Under color Doppler flow imaging (CDFI), the blood flow signals were more frequently detected in HSC lesions (75.7% vs 56.5%, P < 0.05). Resistance index (RI) was higher in HSCs than in HCCs [0.78 (0.70,0.82) vs 0.70 (0.62,0.76), P < 0.05]. On contrast-enhanced ultrasound (CEUS), HSCs mainly showed entirety heterogeneous hyper-enhancement (48.6%), entirety homogeneous enhancement (18.9%), peripheral and internal septal enhancement (18.9%). The incidence of non-enhanced areas inside HSC lesions was higher than that inside HCC lesions (56.8% vs 31.5%, P < 0.05). During the portal venous and late phases, most of the lesions revealed hypo-enhancement in both groups, whereas earlier washout was observed in HSCs [43.0 s (30.5,58.0) vs 60.0 s (46.3,100.0), P < 0.05].

CONCLUSIONS

CEUS features are useful in preoperative and non-invasive differentiation of hepatic sarcomatoid carcinoma and hepatocellular carcinoma.

Common clinicopathological and immunological features of sarcomatoid carcinoma across organs: A histomorphology-based cross-organ study

Sarcomatoid carcinoma (SC), which can occur in any organ, is a rare disease. To elucidate common characteristics of SC beyond organs, we evaluated clinicopathological and immunological features of SC defined by the single histological criterion beyond organs compared to randomly matched conventional carcinoma (non-SC) adjusted for the disease stage. Immunological features were assessed by multiplex immunohistochemistry, comparing immune cell density in tumor tissues and tumor programmed death-ligand 1 (PD-L1) expression. A total of 101 patients with SC or non-SC (31 lung, 19 esophagus, 22 pancreas, 15 liver, 4 bile duct, 6 kidney, 2 uterus and 2 ovary) were identified among 7197 patients who underwent surgery at our institute (1997-2020). SC was significantly associated with worse survival (HR: 1.571; 95% CI: 1.084-2.277; P = .017). The frequency of postoperative progression within 6 months was significantly higher for SC patients (54% vs 28%; P = .002). The immune profiling revealed the densities of CD8+ T cells (130 vs 72 cells/mm2 ; P = .004) and tumor-associated macrophages (566 vs 413 cells/mm2 ; P < .0001) and the tumor PD-L1 expression score (40% vs 5%; P < .0001) were significantly higher in SCs than in non-SCs. Among 73 SC patients with postoperative progression, multivariate Cox regression analysis showed that immunotherapy tended to be associated with favorable survival (HR: 0.256; 95% CI: 0.062-1.057; P = .060). Collectively, SCs shared clinicopathological and immunological features across organs. Our study can initiate to standardize the pathological definition of SC and provide a rationale for the investigation and development for this rare disease in a cross-organ manner.

Surgery after combination therapy with a tyrosine kinase inhibitor and anti-PD-1 antibody in sarcomatoid hepatocellular carcinoma: case report and literature review

Introduction

Although surgery is the preferred treatment for sarcomatoid hepatocellular carcinoma (SHC), the prognosis remains considerably poor due to early postoperative recurrence and metastasis. Reports on surgery after combined treatment with a tyrosine kinase inhibitor and anti-programmed cell death (PD)-1 antibody are unavailable.

Case presentation

A 69-year-old male patient with SHC was admitted to our hospital for treatment of a liver tumor that was detected on ultrasonography. Abdominal computed tomography with triple-phase enhancement revealed a lesion in the right hepatic lobe that measured 86.0 mm × 75.0 mm × 71.0 mm. Biopsy revealed a pathological diagnosis of liver sarcoma or sarcomatoid carcinoma. The patient subsequently received transcatheter arterial chemo-embolization, as he did not consent to surgery. More than two months later, he received a combination of lenvatinib with camrelizumab, as computed tomography showed an increase in the lesion size (to 123.0 mm × 90.0 mm × 80.0 mm) and lateral growth posterior to the upper pole of the right kidney. Liver resection was performed after 6 months of systemic therapy; pathological examination confirmed a diagnosis of SHC and showed extensive necrosis of tumor cells. Combined treatment with lenvatinib and camrelizumab was continued for 6 months after surgery. The patient has survived for over 24 months after initial diagnosis and is currently tumor-free.

Conclusion

Combined systemic therapy with a tyrosine kinase inhibitor and anti-PD-1 antibody may represent a feasible treatment strategy for improving resectability in cases of unresectable SHC. The outcomes with this combination may also be explored in cases of resectable SHC that have a high-risk of recurrence; this may improve the therapeutic effect.

Dynamic contrast-enhanced CT and clinical features of sarcomatoid hepatocellular carcinoma

PURPOSE

To investigate the dynamic contrast-enhanced computed tomography (CECT) features and clinical characteristics of sarcomatoid hepatocellular carcinoma (S-HCC).

METHODS

We retrospectively reviewed the CECT data and clinical findings of 13 patients (11 male and 2 female, with an average age of 58.6 ± 11.2 years) with pathologically proven S-HCC, including 9 patients with surgical resection and 4 patients with biopsy examination. All patients underwent CECT scans. Two radiologists reviewed and evaluated general features, CECT features and extratumoral features of each lesions based on a consensus.

RESULTS

Among the thirteen tumors, a mean size of 66.7 mm was observed, ranging in diameter from 30 to 146 mm. Seven of thirteen patients had hepatitis B virus (HBV) infection and an elevation of alpha-fetoprotein (AFP) level. Most of cases located in the right lobe of liver (84.6%, 11/13). Nine of thirteen tumors showed lobulated or wavy contours and infiltrative morphology, while eight tumors presented with unclear margin. The tumor textures were mainly heterogeneous for ischemia or necrosis, with solid components dominantly in all cases. Eight of thirteen tumors exhibited "slow-in and and slow-out" dynamic enhancement pattern in CECT, with a enhancement peak in the portal venous phase. Portal vein or hepatic thrombus, adjacent organs invasion and lymph node metastasis were observed in two patients, respectively. Four of thirteen lesions occurred intrahepatic metastasis and hepatic surface retraction respectively.

CONCLUSION

S-HCC gengerally seen in elderly male with HBV infection and elevated AFP level. The CT manifestations including: large diameter, frequently hepatic right lobe involvement, lobular or wavy contours, ill-defined margins, infiltrative morphology, obvious heterogeneity and dynamic enhancement pattern of "slow-in and and slow-out" , contributed to the diagnosis of S-HCC. These tumors usually occurred hepatic surface retraction and intrahepatic metastasis.

Tumor Mutational Burden for Predicting Prognosis and Therapy Outcome of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC), the primary hepatic malignancy, represents the second-highest cause of cancer-related death worldwide. Many efforts have been devoted to finding novel biomarkers for predicting both patients' survival and the outcome of pharmacological treatments, with a particular focus on immunotherapy. In this regard, recent studies have focused on unravelling the role of tumor mutational burden (TMB), i.e., the total number of mutations per coding area of a tumor genome, to ascertain whether it can be considered a reliable biomarker to be used either for the stratification of HCC patients in subgroups with different responsiveness to immunotherapy, or for the prediction of disease progression, particularly in relation to the different HCC etiologies. In this review, we summarize the recent advances on the study of TMB and TMB-related biomarkers in the HCC landscape, focusing on their feasibility as guides for therapy decisions and/or predictors of clinical outcome.

Genetic testing and prognosis of sarcomatoid hepatocellular carcinoma patients

Background

Sarcomatoid hepatocellular carcinoma (SHC) is a rare epithelial malignancy with high invasiveness and poor prognosis. However, the molecular characteristics and main driver genes for SHC have not been determined. The aim of this study is to explore the potentially actionable mutations of driver genes, which may provide more therapeutic options for SHC.

Methods

In this study, DNA extraction and library preparation were performed using tumor tissues from 28 SHC patients. Then we used Miseq platform (Illumina) to sequence the target-enriched library, and we aligned and processed the sequencing data. The gene groups were tested for SNVs/Indels/CNVs. Tumor mutation burden (TMB) was assessed by the 425-cancer-relevant gene panel. Multivariate analysis of COX's model was used for survival analysis (OS) of patients' clinical characteristics.

Result

The median overall survival (OS) of the patients was only 4.4 months. TP53, TERT, and KRAS were the top three frequently mutated genes, with frequencies of 89.3%, 64.3%, and 21.4%, respectively. A considerable number of patients carried mutations in genes involved in the TP53 pathway (96%) and DNA Damage Repair (DDR) pathway (21%). Multiple potentially actionable mutations, such as NTRK1 fusions and BRCA1/2 mutations, were identified in SHCs.

Conclusions

This study shows a landscape of gene mutations in SHC. SHC has high mutation rates in TP53 pathway and DDR pathway. The potentially actionable mutations of driver genes may provide more therapeutic options for SHC. Survival analysis found that age, smoking, drinking, and tumor diameter may be independent prognostic predictors of SHC.

Hepatic Sarcomatoid Carcinoma Is an Aggressive Hepatic Neoplasm Sharing Common Molecular Features With Its Conventional Carcinomatous Counterparts

Hepatic sarcomatoid carcinoma is a rare hepatic tumor with an aggressive clinical behavior and dismal outcome. However, the molecular pathogenesis is incompletely defined. In this study, we analyzed 59 hepatic sarcomatoid carcinomas using targeted next-generation sequencing and immunohistochemistry. A panel of 14 genes commonly mutated in primary liver carcinomas was examined. PD-L1 and loss of expression for switch/sucrose nonfermenting complexes, including BAP1, ARID1A, ARID2, and PBRM1, were detected by immunohistochemistry. The 59 hepatic sarcomatoid carcinomas encompass various carcinomatous subtypes and tumors with complete sarcomatoid transformation. Mutations in TP53 and promoter of TERT (pTERT) were frequently identified in sarcomatoid hepatocellular carcinoma, sarcomatoid combined hepatocellular cholangiocarcinoma, and hepatic sarcomatoid carcinomas with complete sarcomatoid transformation but rarely in sarcomatoid cholangiocarcinoma. Alterations involving switch/sucrose nonfermenting complexes were uncommon in hepatic sarcomatoid carcinoma (n = 2). PD-L1 expressed in tumor-associated immune cells in 67% of the tumors and in tumor cells in 33% of the tumors. A multivariate survival analysis indicated that PD-L1 expression in immune cells served as an independent favorable predictive factor of patient survival (P = .036). In conclusion, hepatic sarcomatoid carcinoma displays molecular similarity with its conventional carcinomatous counterparts. This finding suggests persistent genetic characteristics during sarcomatous evolution. PD-L1 expression in immune cells is a favorable prognostic factor for patient outcomes and may be a potential biomarker for immunotherapeutic treatment.

Epidemiological and Clinical Characteristics of Five Rare Pathological Subtypes of Hepatocellular Carcinoma

Background

Hepatocellular carcinoma (HCC) is a highly heterogeneous tumor with several rare pathological subtypes and which is still poorly understood. This study aimed to describe the epidemiological and clinical spectrum of five rare HCC subtypes and develop a competing risk nomogram for cancer-specific survival prediction.

Methods

The study cohort was recruited from the Surveillance, Epidemiology, and End Results database. The clinicopathological data of 50,218 patients histologically diagnosed with classic HCC and five rare subtypes (ICD-O-3 Histology Code = 8170/3-8175/3) between 2004 and 2018 were reviewed. The annual percent change (APC) was calculated utilizing Joinpoint regression. The nomogram was developed based on multivariable competing risk survival analyses. Akaike information criterion, Bayesian information criterion, C-index, calibration curve, and area under the receiver operating characteristic curve were obtained to evaluate the prognostic performance. A decision curve analysis was introduced to examine the clinical value of the models.

Results

Despite scirrhous carcinoma, which showed a decreasing trend (APC = -6.8%, P = 0.025), the morbidity of other rare subtypes remained stable from 2004 to 2018. The incidence-based mortality was plateau in all subtypes during the period. Clear cell carcinoma is the most common subtype (n = 551, 1.1%), followed by subtypes of fibrolamellar (n = 241, 0.5%), scirrhous (n = 82, 0.2%), spindle cell (n = 61, 0.1%), and pleomorphic (n = 17, ~0%). The patients with fibrolamellar carcinoma were younger and more likely to have a non-cirrhotic liver and better prognoses. Scirrhous carcinoma shared almost the same macro-clinical characteristics and outcomes as the classic HCC. Clear cell carcinoma tended to occur in the Asia-Pacific elderly male population, and more than half of them were large HCC (Size&gt;5cm). Sarcomatoid (including spindle cell and pleomorphic) carcinoma was associated with a larger tumor size, poorer differentiation, and more dismal prognoses. The pathological subtype, T stage, M stage, surgery, alpha-fetoprotein, and cancer history were confirmed as the independent predictors in patients with rare subtypes. The nomogram showed good calibration, discrimination, and net benefits in clinical practice.

Conclusion

The rare subtypes had unique clinicopathological features and biological behaviors compared with the classic HCC. Our findings could provide a valuable reference for clinicians. The constructed nomogram could predict the prognoses with good performance, which is meaningful to individualized management.