Cytogenetic and immunohistochemical biomarker profiling of therapy-relevant factors in salivary gland carcinomas

Tumor-infiltrating lymphocytes and tumor-associated macrophages as potential predictors of lymph node metastases in major salivary gland cancers

Purpose

The purpose of this study is to define if tumor-infiltrating lymphocytes (TILs) and tumor-associated macrophages (TAMs) could represent potential predictors of lymph node metastases (LNM) in salivary gland cancers (SGC).

Methods

A selected number of immunohistochemical markers related to TILs (CD3, CD4, CD68, and FOXP3) and TAMs (CD68 and CD163) were investigated on major salivary gland cancers. TIL and TAM densities were measured on digital images using the open-source QuPath both in the tumor interior (TI) and invasive margin (IM). Correlation with pathologic N classification and follow-up clinical data was investigated.

Results

A total of 25 consecutive patients (men: 11; median age: 62.0) were included. Densities of CD3+ IM (OR = 7.7, 95% CI 1.2-51.2), CD8+ TI (OR = 7.7, 95% CI 1.2-51.2), CD8+ IM (OR = 7.7, 95% CI 1.2-51.2), FOXP3+ TI (OR = 24.0, 95% CI 2.2-255.9), CD68+ TI (OR = 7.7, 95% CI 1.2-51.2), and CD163+ IM (OR = 7.7, 95% CI 1.2 - 51.2), and the Immunoscore CD8/CD3 (OR = 1.9, 95% CI 1.1-3.4) were significantly associated with LNM (p < 0.05). CD3+ TI density was significantly associated with tumor recurrence and death (HR = 5.8, 95% CI 1.5-22.6; p < 0.05).

Conclusion

A high density of specific TIL and TAM subpopulations might be correlated with a higher probability of LNM in SGC.

Prognostic Impact of Tumor Immune Microenvironment and Its Predictive Role in Salivary Gland Cancer

BACKGROUND

Recently, many studies have investigated the role of tumor immune microenvironment (TIME) in carcinogenesis, highlighting its relation to both tumor regression and progression. In particular, the "inflammatory system", made of innate and adaptive immune cells, interacts with cancer cells and their surrounding stroma. In this setting, the aim of this review is to summarize the current literature regarding the TIME of major salivary gland carcinomas (MSGCs), with particular attention on the characteristics and prognostic role of tumor infiltrating lymphocytes (TILs), the mechanisms that lead to TILs exhaustion and the important additional immune infiltrating factors that help SGC progression or remission.

METHODS

A comprehensive literature search was performed concerning published articles on the role of TIME in MSGCs.

RESULTS

In this work we summarize the advancing knowledge on TIME in SGCs by demonstrating the key prognostic and/or predictive value of specific immune features.

CONCLUSION

From the analysis of the current 'status of the art' it clearly emerges a need for precise, unambiguous phenotyping of immune cell populations, as well as a more thorough understanding of the frequencies and interactions of multiple immune cell types inside the TIME and their spatial localization (intratumoral vs. stromal).

HER2 Positivity in Histological Subtypes of Salivary Gland Carcinoma: A Systematic Review and Meta-Analysis

Background

HER2 aberrations in salivary gland carcinomas (SGC) as well as benefit of HER2 directed therapy have been reported in small studies. However, reliable estimates of the prevalence of HER2 positivity in SGC and its various histological subtypes are lacking.

Objective

To assess the prevalence of HER2 positivity in histological subtypes of salivary gland carcinomas (SGC).

Methods

Studies were identified by a systematic review of the literature. Data on in situ hybridization (ISH) and immunohistochemistry (IHC) were extracted to derive pooled prevalence estimates calculated by a random effects model. Characteristics of the studies were extracted for subgroup analysis.

Results

Fifty studies including 3372 patients were identified, providing data on sixteen histological subtypes. Based on the meta-analysis, the estimated prevalence of HER2 positivity were 43% (95% CI: 36% – 51%) in salivary duct carcinoma (SDC), 39% (95% CI: 32% – 45%) in carcinoma ex pleomorphic adenoma (CEP), 17% (95% CI: 7.5% – 33%) in squamous cell carcinoma (SCC), 13% (95% CI: 7.6% – 21%) in adenocarcinoma NOS (ADC), 6.7% (95% CI: 0.17%-32%) in poorly differentiated carcinoma, 5.5% (95% CI: 2.9% – 9.6%) in mucoepidermoid carcinoma, 4.3% (95% CI: 1.4% – 13%) in myoepithelial carcinoma, 1.8% (95% CI: 0.04%-9.6%) in epithelial-myoepithelial carcinoma, 0.45% (95% CI: 0.0097% – 18%) in acinic cell carcinoma and 0.15% (0.037% – 5.4%) in adenoid cystic carcinoma. Estimates for five additional subtypes were assessed.

Conclusion

Prevalence of HER 2 positivity in SGC varies greatly based on histological subtype, with SDC, CEP, SCC, and ADC displaying the highest rates.

Management of Salivary Gland Malignancy: ASCO Guideline

PURPOSE

To provide evidence-based recommendations for practicing physicians and other healthcare providers on the management of salivary gland malignancy.

METHODS

ASCO convened an Expert Panel of medical oncology, surgical oncology, radiation oncology, neuroradiology, pathology, and patient advocacy experts to conduct a literature search, which included systematic reviews, meta-analyses, randomized controlled trials, and prospective and retrospective comparative observational studies published from 2000 through 2020. Outcomes of interest included survival, diagnostic accuracy, disease recurrence, and quality of life. Expert Panel members used available evidence and informal consensus to develop evidence-based guideline recommendations.

RESULTS

The literature search identified 293 relevant studies to inform the evidence base for this guideline. Six main clinical questions were addressed, which included subquestions on preoperative evaluations, surgical diagnostic and therapeutic procedures, appropriate radiotherapy techniques, the role of systemic therapy, and follow-up evaluations.

RECOMMENDATIONS

When possible, evidence-based recommendations were developed to address the diagnosis and appropriate preoperative evaluations for patients with a salivary gland malignancy, therapeutic procedures, and appropriate treatment options in various salivary gland histologies.Additional information is available at www.asco.org/head-neck-cancer-guidelines.

The expression of PD-L1 in salivary gland carcinomas

Objective was to analyze the role of PD-L1 and its relation to demographic, patho-clinical and outcome parameters in salivary gland carcinoma (SGC) patients. Patients treated for salivary gland carcinomas between 1994 and 2010 were included. A retrospective chart review for baseline characteristics, pathohistological, clinical and outcome data was performed. Immunohistochemistry for PD-L1 was performed using tissue microarrays. PD-L1 expression was assessed in tumor cells and tumor-infiltrating immune cells (TIIC) and statistical analysis with regard to baseline and outcome data was performed. Expression of PD-L1 (by means ≥1% of the cells with PD-L1 positivity) was present in the salivary gland carcinoma cells of 17%, in the TIIC of 20% and in both tumor cells and TIIC of 10% the patients. PD-L1 expression in tumor cells and both tumor cells and TIIC was related to tumor grading (p = 0.035 and p = 0.031, respectively). A trend towards higher grading was also seen for PD-L1 expression in TIICs (p = 0.058). Patients with salivary duct carcinomas and PD-L1 expressing TIICs showed a significantly worse DFS and OS (p = 0.022 and p = 0.003, respectively), those with both tumor cells and TIIC expressing PD-L1 a significantly worse DFS (p = 0.030). PD-L1 expression is present in 17% and 20% of salivary gland carcinoma cells and TIIC. Ten percent of the patient showed a PD-L1 positivity in both tumor cells and TIIC. This is related to high tumor grading and therefore might be a negative prognostic factor.

Molecular defects in BRAF wild-type ameloblastomas and craniopharyngiomas-differences in mutation profiles in epithelial-derived oropharyngeal neoplasms

The aim of this study was to evaluate the mutation profile of BRAF wild-type craniopharyngiomas and ameloblastomas. Pre-screening by immunohistochemistry and pyrosequencing for identifying BRAF wild-type tumors was performed on archived specimens of ameloblastic tumors (n = 20) and craniopharyngiomas (n = 62). Subsequently, 19 BRAF wild-type tumors (nine ameloblastic tumors and ten craniopharyngiomas) were analyzed further using next-generation sequencing (NGS) targeting hot spot mutations of 22 cancer-related genes. Thereby, we found craniopharyngiomas mainly CTNNB1 mutated (8/10), including two FGFR3/CTNNB1-double mutated tumors. Ameloblastic tumors were often FGFR2 mutated (4/9; including one FGFR2/TP53/PTEN-triple mutated case) and rarely CTNNB1/TP53-double mutated (1/9) and KRAS-mutated (1/9). In the remaining samples, no mutation could be detected in the 22 genes under investigation. In conclusion, mutation profiles of BRAF wild-type craniopharyngiomas and ameloblastomas share mutations of FGFR genes and have additional mutations with potential for targeted therapy.

[Analysis of therapy-relevant receptors in bone marrow carcinosis : Comparison of pathological and clinical parameters]

BACKGROUND

Bone marrow carcinosis is a sign of advanced tumor stage with nonspecific clinical and hematological symptoms. Diagnosis is based on bone marrow biopsy and histopathology, but biopsies are not part of the standard work-up in oncological diseases and data on the correlation between clinical presentation and pathological findings are sparse.

MATERIAL AND METHODS

In a retrospective single-center study, data from 20 tumor patients with bone marrow carcinosis were analyzed. Bone marrow biopsies were re-evaluated regarding quantity of tumor cells, fibrosis/necrosis, and bone changes. Immunohistochemistry of potential therapy-relevant receptors and PD-L1 was performed.

RESULTS

The median age in these 20 patients (13 women, 7 men) was 65 years. The most frequent diagnoses were breast (n = 8) and lung cancer (n = 5). Anemia (94% of patients), thrombocytopenia (72%), and elevated LDH (83%) were frequent findings. The degree of bone marrow infiltration was highly variable and accounted for between 1 and 95% of biopsy space. Significant bone remodeling was present in 14/20 biopsies. No correlation could be found between histological and radiological findings. Treated patients showed some clinical and biochemical improvement, but the overall survival was poor (median 4.5 months, range < 0.5 to 21.5 months).

DISCUSSION

Anemia and thrombocytopenia are frequently associated with bone marrow carcinosis, but are nonspecific. The extent of tumor cell infiltration and osteolytic/osteoblastic changes did not correlate with radiological findings. Therapy-relevant target factors should be evaluated, but therapeutic options are often limited and the prognosis is bad.

New concepts of personalized therapy in salivary gland carcinomas

Salivary gland carcinomas are rare tumours and therapy strategies are less standardized than in lung, gastric or breast cancer. Therapy is based on surgery, but not all carcinomas are completely resectable, e.g. because carcinomas often show infiltration of nerves. For further therapy decision pathology is recommended, but evaluation of potential targets for personalized therapy is not part of the routine panel. Many salivary gland carcinomas can be resistant to radio- and/or chemotherapy, which limits therapeutic options. This review summarizes new concepts for personalized therapy in salivary gland carcinoma patients. Targeting growth receptors HER2, EGFR, AR and ER is possible but, in some studies, potential target molecules were not adequately tested before therapy. In addition, approximately 20-25% of carcinomas have RAS mutation (mainly H-RAS), which could explain resistance to therapy. Possible therapy options in the future could be immunomodulation (inhibition of PDL1/PD1 signalling), nanoparticles (gold nanoparticles conjugated to cetuximab can increase radiosensitivity) and drug delivery systems (trastuzumab emtansine/T-DM1).