Hepatocellular carcinoma with immature T-cell (T-lymphoblastic) proliferation

Immunotherapy for hepatocellular carcinoma

ABSTRACT

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related deaths worldwide. Its high recurrence rate and lack of effective control drugs result in a 5-year survival rate of only about 10%. HCC is a tumor regulated by the immune system. Significant breakthroughs have occurred in treating solid tumors with immunotherapy in recent years. Various immunotherapies, such as immune checkpoint inhibitors (ICIs), including combination therapies, have demonstrated promising therapeutic effects in both clinical applications and research. Other immunotherapies, such as adoptive cell therapies and oncolytic viruses, are also emerging, offering hope for addressing long-term survival issues in HCC. This article reviews current commonly used immunotherapy strategies and the latest research findings for reference.

Clinicopathological characteristics and molecular analysis of lymphocyte-rich hepatocellular carcinoma

Lymphocyte-rich hepatocellular carcinoma (LR-HCC), a newly proposed subtype of HCC, is characterized with abundant lymphocyte infiltration in the tumor. LR-HCC has a relatively good prognosis and is quite rare (<1% of all HCC). We examined LR-HCC clinicopathological and molecular characteristics by analyzing 451 surgically resected HCC cases without any prior treatment history at our hospital between 2012 and 2021. Clinicopathological features of LR-HCC and other HCCs (non-LR-HCC) were compared. Neoplastic and nonneoplastic hepatocytes from LR-HCC (n = 4) were collected with a laser microdissection system; RNA was extracted, followed by microarray analysis to examine lymphocytic infiltration-related molecular targets. Immunohistochemical staining of identified molecular target was performed in LR-HCC and non-LR-HCC. CD3, CD20, and CD8 immunostaining was also performed in LR-HCCs. There were 28 cases of LR-HCC (6%). No statistically significant differences were found in clinicopathological features, except for gross type, between LR-HCC and non-LR-HCC cases. The LR-HCC 5-year survival rate was >90%. Microarray analysis revealed high CCL20 expression in LR-HCC cases; immunohistochemical study showed significantly higher CCL20 expression in LR-HCC (P < 0.01) than in non-LR-HCC. CCR6, the only CCL20 receptor, was observed in infiltrating lymphocytes and HCC cells in LR-HCC. There were significantly more CD3-positive cells than CD20-positive cells (P < 0.0001) in tumor-infiltrating lymphocytes, most of which were CD8-positive T cells. In conclusion, there were no significant differences in clinicopathological characteristics between LR-HCC and non-LR-HCC, except for gross and LR microscopic features. CCL20 expression in LR-HCC may contribute to infiltration of large numbers of CD8-positive lymphocytes.

Indolent T-lymphoblastic proliferation involving hepatocellular carcinoma-presentation in novel settings and comprehensive review of literature

Indolent T-lymphoblastic proliferation (iT-LBP) is a rare, non-clonal, extrathymic lymphoid proliferation with an immature T cell phenotype, indolent clinical course, and excellent prognosis. Although their pathogenesis is unclear, they are reported to be associated with Castleman disease, follicular dendritic cell tumors/sarcomas, angioimmunoblastic T cell lymphoma, hepatocellular carcinoma (HCC), myasthenia gravis, and acinic cell carcinoma. There are around 51 reported cases of iT-LBP in the literature. Recognition and accurate diagnosis of this entity is critical as it shares morphologic and immunophenotypic features with an aggressive malignancy-acute T cell leukemia/lymphoma (T-ALL). IT-LBP in HCC post-liver transplant and in metastatic sites has not been reported in the literature. Two case reports of patients presenting with recurrent and metastatic HCC in post-liver transplant settings are described. A 50-year-old man with an end-stage liver disease with HCC underwent liver transplant. A year later, he developed pulmonary metastasis with associated iT-LBP. A 69-year-old man underwent liver transplant for end-stage liver disease and HCC. Eighteen months later, he developed recurrent HCC in the transplanted liver and omental metastasis; both sites showed HCC with iT-LBP. iT-LBP in both patients expressed TdT, CD3, and CD4 and lacked CD34 and clonal T cell receptor gene rearrangements. On retrospective review, the pre-transplant HCC specimens lacked iT-LBP. We present two cases of iT-LBP associated with HCC in novel settings-in post-liver transplant patients and in recurrent/metastatic sites of HCC. In addition, a comprehensive literature review of clinical, histological, and immunophenotypic characteristics of reported cases of iT-LBP is presented.

Indolent T-lymphoblastic proliferation with fibrolamellar hepatocellular carcinoma developed after colorectal adenocarcinoma: a case report

Objective: Indolent T-lymphoblastic proliferation (iT-LBP) is a non-neoplastic disease with an indolent clinical course, manifesting as hyperplasia of immature extrathymic T-lymphoblastic cells. Isolated iT-LBP has been observed, but the majority of iT-LBP cases has been seen in conjunction with other diseases. iT-LBP is easily misdiagnosed as T-lymphoblastic lymphoma/leukemia, and understanding the disease of indolent T-lymphoblastic proliferation may prevent misdiagnosis and missed diagnosis in pathological diagnosis. Case presentation: We report a case morphology, immunophenotypic, and molecular features of iT-LBP combined with fibrolamellar hepatocellular carcinoma developed after colorectal adenocarcinoma and review relevant literature. Conclusion: iT-LBP combined with fibrolamellar hepatocellular carcinoma developed after colorectal adenocarcinoma is relatively rare and should always be considered as a differential diagnosis of T-lymphoblastic lymphoma and scirrhous hepatocellular carcinoma as the two disorders show highly similar clinical features.

Indolent T-lymphoblastic proliferation: A systematic review of the literature analyzing the epidemiologic, clinical, and pathologic features of 45 cases

An indolent T-lymphoblastic proliferation (iT-LBP) is a rare benign disorder characterized by an abnormal expansion of immature T-cells, which morphologically can mimic malignancy. Since the first case was described in 1999, dozens more have been reported in the literature. However, the epidemiologic, clinical, pathologic, and biologic features of this disease have not been well described. Here, we retrospectively reviewed all known cases reported in the literature to better understand this entity. A PubMed search up to January 2022 highlighted 25 papers describing cases/case series of iT-LBP, one of which was a case presentation in a slide workshop. Except for 9 of the cases in one of the papers, where it was evident that the number of CD3+/TdT+ cells were too few to conform with a diagnosis of iT-LBP, all papers and all the cases reported were included in the study amounting to a total of 45 cases. Clinicopathologic characteristics were analyzed using descriptive statistics and frequencies. Our analysis highlighted the previously known association with Castleman disease and Castleman-like features and underlined its association with dendritic cell proliferations in general, as well as uncovering high frequency of concurrence with hepatocellular carcinoma and autoimmune diseases, most notably myasthenia gravis, paraneoplastic pemphigus and paraneoplastic autoimmune multiorgan syndrome. Furthermore, the co-expression of CD4 and CD8 and high prevalence of extranodal disease and recurrences were other less well described features that were revealed.

Indolent T-lymphoblastic proliferation associated with Castleman disease and low grade follicular dendric cell sarcoma: report of a case and review of literature

Indolent T-lymphoblastic proliferation (IT-LBP) is referred to as extrathymic immature TDT+T-cell hyperplasia, non-neoplastic lesion, often misdiagnosed as T-lymphoblastic lymphoma and overtreated. We report a case of a 20-year-old male patient with a right adrenal gland mass, diagnosed as indolent T-lymphoblastic proliferation (IT-LBP) associated with hyaline vascular Castleman disease (HV-CD) and low grade follicular dendric cell sarcoma (LG-FDCS). The case is a rare combination of finding, and it is the first case occurring in adrenal gland. IT-LBP is a clinically indolent disease, requiring no treatment, often associated with other tumors. Because of the high ki67 index, IT-LBP is easily misdiagnosed as T-lymphoblastic lymphoma, causing overtreatment. Understanding the biological behavior, treatment, prognosis and the associated diseases of IT-LBP is important.

Hepatic carcinoma with indolent T-lymphoblastic proliferation (iT-LBP)

Although indolent T-lymphoblastic proliferation (iT-LBP) in the extrathymic location have been shown to be a distinct clinicopathologic entity, carcinoma composed iT-LBP are rare. We retrospectively analyzed the clinicopathological features of 7 hepatic carcinoma cases with iT-LBP. There were 5 male and 2 female patients, aged from 37-54 (mean 47) years. All patients had a clinical history of chronic hepatitis B viral infection with high serum AFP level. Microscopically, these carcinomas were characterized by admixed with increased amounts of fibrous and small lymphocytes composed of regressive germinal centers. Immunohistochemically, in lymphoid tissues, some TDT⁺ cells were highlighted in the CD3+ area. These lymphoblasts localized predominantly between the cords of the carcinoma and interfollicular regions, diffused or only focal presented more than 50 TdT⁺ lymphoblasts/HPF. No EBV infection cells and T-cell antigen clonal rearrangement was detected. 3/4 cirrhotic patients developed HCC recurrence, while the 4-y survival rate was 100% in non-cirrhosis patients. It-LBP is a rare unusual proliferation and easily be misdiagnosed in HC patients. It does not seem to be associated with a specific HCC type. If HC companied with numerous small lymphocytes infiltration and showed high Ki67 index, a primary HC with iT-LBP should be considered in the lists of diagnosis.

Indolent T-lymphoblastic proliferation concomitant with acinic cell carcinoma mimicking T-lymphoblastic lymphoma: case report and literature review

AIMS

Indolent T-lymphoblastic proliferation (iT-LBP) is a non-clonal benign condition showing extrathymic proliferation of T-lymphoblasts positive for CD3, CD4, CD8, and TdT. Isolated iT-LBP has been observed, but the majority of iT-LBPs have been seen in conjunction with other disorders, including Castleman disease, hepatocellular carcinoma, follicular dendritic cell tumours, angioimmunoblastic T-cell lymphoma, myasthenia gravis, and acinic cell carcinoma (ACC). The clinical course of iT-LBP is indolent, and no therapy is usually required. A major concern is misdiagnosis as T-lymphoblastic lymphoma, and a correct diagnosis of iT-LBP often requires not only pathological analysis but also careful monitoring of the clinical course. The aim of this study was to broaden the knowledge of pathologists and physicians concerning this as yet not well-recognised entity.

METHODS AND RESULTS

We report a case of iT-LBP concomitant with ACC, along with a literature review of all 14 cases of iT-LBP reported to date.

CONCLUSIONS

iT-LBP should always be considered as a differential diagnosis of T-lymphoblastic lymphoma, as the two disorders show extremely similar traits.

CXCR4 inhibition in tumor microenvironment facilitates anti-programmed death receptor-1 immunotherapy in sorafenib-treated hepatocellular carcinoma in mice

Sorafenib, a broad tyrosine kinase inhibitor, is the only approved systemic therapy for advanced hepatocellular carcinoma (HCC) but provides limited survival benefits. Recently, immunotherapy has emerged as a promising treatment strategy, but its role remains unclear in HCCs, which are associated with decreased cytotoxic CD8(+) T-lymphocyte infiltration in both murine and human tumors. Moreover, in mouse models after sorafenib treatment intratumoral hypoxia is increased and may fuel evasive resistance. Using orthotopic HCC models, we now show that increased hypoxia after sorafenib treatment promotes immunosuppression, characterized by increased intratumoral expression of the immune checkpoint inhibitor programmed death ligand-1 and accumulation of T-regulatory cells and M2-type macrophages. We also show that the recruitment of immunosuppressive cells is mediated in part by hypoxia-induced up-regulation of stromal cell-derived 1 alpha. Inhibition of the stromal cell-derived 1 alpha receptor (C-X-C receptor type 4 or CXCR4) using AMD3100 prevented the polarization toward an immunosuppressive microenvironment after sorafenib treatment, inhibited tumor growth, reduced lung metastasis, and improved survival. However, the combination of AMD3100 and sorafenib did not significantly change cytotoxic CD8(+) T-lymphocyte infiltration into HCC tumors and did not modify their activation status. In separate experiments, antibody blockade of the programmed death ligand-1 receptor programmed death receptor-1 (PD-1) showed antitumor effects in treatment-naive tumors in orthotopic (grafted and genetically engineered) models of HCC. However, anti-PD-1 antibody treatment had additional antitumor activity only when combined with sorafenib and AMD3100 and not when combined with sorafenib alone.

CONCLUSION

Anti-PD-1 treatment can boost antitumor immune responses in HCC models; when used in combination with sorafenib, anti-PD-1 immunotherapy shows efficacy only with concomitant targeting of the hypoxic and immunosuppressive microenvironment with agents such as CXCR4 inhibitors.

Indolent T-lymphoblastic proliferation with disseminated multinodal involvement and partial CD33 expression

Although indolent T-lymphoblastic proliferations (iT-LBP) are rare, this diagnosis should be excluded in any patient with an extrathymic proliferation of immature TdT+T cells. Unlike T-lymphoblastic leukemia/lymphoma, patients with iT-LBP do not require chemotherapy. We report a case of iT-LBP with disseminated multinodal involvement in an otherwise healthy 49-year-old woman. Multiple lymph node biopsies were performed over the course of several months demonstrating persistent and anatomically diffuse involvement. Over 18 months, and without therapy, she has remained healthy, and her lymphadenopathy significantly improved. No bone marrow or peripheral blood involvement was ever identified. Atypical T cells showed an immunophenotypic spectrum of T-cell antigen expression with partial CD33 on a subset of T cells detected by both flow cytometry and immunohistochemistry. Both T-cell clonality and Human Androgen Receptor Assay (HUMARA) studies, performed on lymph node biopsy specimens, were negative. This case represents the first detailed clinical, morphologic, molecular, and immunophenotypic description of disseminated multinodal involvement by nonclonal iT-LBP with partial CD33 expression on T cells.

Indolent T-lymphblastic proliferation: report of a case involving the upper aerodigestive tract

T-lymphoblastic lymphoma (T-LBP) is a high-grade malignant lymphoma, which possesses the characteristic of high metastasis and high mortality without treatment. We are presenting a special T-lymphoblastic proliferation involving in the oropharynx, nasopharynx, sinus and trachea in a patient with local involved about 15-years without systemic dissemination. The immunophenotype of this case was similar to T-LBP. The proliferous cells were positive for terminal deoxynucleotidyl transferase (TdT), CD3, and appeared co-expression CD4 and CD8. No clonal rearrangements of TCRγ and/or TCRβ gene were detected. Indolent T-lymphoblastic proliferations rarely occurred or unusually could not be diagnosed, combing with the relevant literature and clinically indolent manifestation, we interpreted this case as indolent T-lymphoblastic proliferation (iT-LBPs). So far, the mechanism of the T-lymphoblastic proliferations is still uncertain and requires further study.

Nasopharyngeal tonsils (adenoids) contain extrathymic corticothymocytes

Adenoidal tissue (also known as nasopharyngeal tonsils) of 58% of humans in the pediatric age group contains immature T-lymphoid cells with the phenotype of thymocytes (TdT+,CD1abc+, cytoplasmic CD3+, coexpressing CD4 and CD8, lacking an Intraepithelial Lymphocyte-associated phenotype). The notable difference in comparison to palatine tonsils is the clustering in groups and sheets, comprising hundreds or thousands of cells (1.7%±0.2 of total T cells). The thymic epithelium is morphologically and phenotypically absent. Adenoids share with tonsils and lymph nodes the presence of immature B cell precursors (TdT+, CD1a-, Pax5+, Surrogate light chain±), however in these latter the presence of TdT+, CD1a+, Pax5- precursors is absent or limited to individual cells. Human adenoids are distinct among the Waldeyer's ring lymphoid tissue because of the known embryogenic derivation from the third pharyngeal pouch, from which the thymus develops; in addition, they may display phenotypic incomplete features of a vestigial thymus.

Uterine leiomyoma with indolent B-lymphoblastic proliferation

Uterine leiomyoma with TdT positive B lymphocytes infiltrating is very rare and may simulate precursor B-cell lymphoblastic lymphoma (B-LBL). To the best of our knowledge, this is the first description of such a lesion in English literature. A 51-year-old Chinese woman was noted a mass in her uterus in a routine physical examination. The myomectomy specimen was identified as a well-defined 8.0x6.8 cm tumor and the cut surface was fresh and yellow-tan. A massive small lymphocytic infiltration accompanied by plasma cells and histiocytes was noted in the leiomyoma but not in the surrounding non-neoplastic myometrial fibers. These cells were small in size without significant nuclear irregularities and mitotic figures can not been seen. Immunohistochemical analysis has shown some small lymphocytes were CD20+, CD79a+, Pax5+B cells and some were CD2+, CD3+, CD5+, CD43+T cells. The small B cells coexpressed TdT and Ki67 and were in patchy dense distribution. The postoperative course was uneventful within a 30-month follow-up period without chemotherapy and radiotherapy. The true nature of these TdT(+) B cells has not been determined.

Indolent T-lymphoblastic proliferation (iT-LBP): a review of clinical and pathologic features and distinction from malignant T-lymphoblastic lymphoma

In recent years, a new pathologic entity has emerged: indolent T-lymphoblastic proliferation (iT-LBP). iT-LBPs share immunophenotypic similarities with T-lymphoblastic lymphoma; however, T-lymphoblastic proliferations are clinically indolent, and unlike the malignant counterpart, these expansions of nonclonal terminal deoxynucleotidyl transferase (TdT)+ T cells do not require treatment. Here we review the clinical and pathologic features, which are required for an accurate diagnosis of an iT-LBP. We demonstrate specific criteria can be used to accurately diagnose iT-LBP, notably: (1) confluent groups of TdT+ T cells in a biopsy specimen, (2) relative preservation of surrounding normal lymphoid architecture, (3) TdT+ T cells without morphologic atypia, (4) absence of thymic epithelium, (5) nonclonal TdT+ T cells, (6) immunophenotype of developmentally normal immature thymic T cells, and (7) clinical evidence of indolence (follow-up >6 mo without progression).

Tumor-infiltrating lymphocytes and hepatocellular carcinoma: pathology and clinical management

The presence of tumor-infiltrating lymphocytes (TILs) in hepatocellular carcinoma (HCC) is relatively rare. The prognosis of patients with HCC and marked TILs is better than that of patients with HCC without TILs. TILs in HCC tissues are mainly T cells, and previous reports suggested that TILs might be important antitumor effector cells. TILs have been extensively analyzed, and subpopulations of CD3(+), CD4(+), and CD8(+) T cells are often present in HCC. Some studies have reported that the percentage of CD8(+) T cells, which might have cytotoxic activity, is decreased in tumors with TILs, as compared with noncancerous tissues. Although the antitumor effects of TILs seem to be impaired in HCCs, the underlying mechanism has remained unclear until quite recently. Pathological and in vitro studies have now shown that regulatory T cells play important roles in the deterioration of the antitumor effects of TILs. The aim of this review is to introduce recent pathological findings for TILs in HCC and to evaluate new therapeutic strategies in this field.