Multicentre, retrospective study of the efficacy and safety of nivolumab for recurrent and metastatic salivary gland carcinoma

Prognostic value of the pretreatment Glasgow prognostic score or modified Glasgow prognostic score in patients with advanced cancer receiving immune checkpoint inhibitors: A systematic review and meta‑analysis

The Glasgow prognostic score (GPS) and modified GPS (mGPS) have value in evaluating the prognosis of patients receiving immune checkpoint inhibitors (ICIs). However, with the continuous emergence of new research, the predictive value of GPS and mGPS for immunotherapy deserves further validation. The aim of the present study was to explore the predictive value of GPS or mGPS on the progression-free survival (PFS) and overall survival (OS) of patients with advanced cancer receiving ICIs. Eligible studies were systematically searched using the PubMed, Embase, Cochrane library and Web of Science databases until November 2022. Published data were extracted and the hazard ratios (HRs) with 95% confidence intervals (CIs) were pooled. A total of 18 studies with 1,355 patients were included in the present study. Patients were divided into the low GPS/mGPS (0) and high GPS/mGPS (1/2/1-2) groups. Overall, the high GPS group had a shorter OS (HR, 2.88; 95% CI, 2.06-4.03) with high heterogeneity, and a shorter PFS (HR, 2.08; 95% CI, 1.55-2.78) with low heterogeneity, compared with the low GPS group. Sensitivity analysis showed that the results were stable and the heterogeneity was significantly reduced from 56.4 to 30.3% after excluding one study. Subgroup analyses by score showed that GPS 1, GPS 2 and GPS 1-2 all had a poorer OS than GPS 0, with low heterogeneity. Overall, the high mGPS group had a poorer OS (HR, 2.56; 95% CI, 1.76-3.72) with low heterogeneity, and a poorer PFS (HR, 2.55; 95% CI, 1.81-3.60) with high heterogeneity, compared with the low mGPS group. The combined effect size was consistent but the heterogeneity was not eliminated after sensitivity analysis. Subgroup analyses by country and score also showed that the country had no effect on the results and that mGPS 1, mGPS 2 and mGPS 1-2 had a poorer PFS than mGPS 0. Therefore, high GPS and mGPS may be effective biomarkers for predicting the survival of patients with cancer receiving ICIs. Patients with high GPS and mGPS may be considered for supportive treatment; however, large prospective trials are needed to validate these findings.

A macrophage-predominant immunosuppressive microenvironment and therapeutic vulnerabilities in advanced salivary gland cancer

Salivary gland cancers are rare, diverse malignancies characterized by poor response to immunotherapy. The tumor immune environment in these cancers remains poorly understood. To address this, we perform an integrative analysis of the tumor immune microenvironment in a large cohort of advanced salivary gland cancer samples. Most tumors exhibit low immune activity with limited immune cell infiltration. Inflammation is linked to higher tumor mutational burden in non-adenoid cystic carcinoma histologies. Subtype specific expression of immune checkpoints is identified with prominent expression of VTCN1 in luminal-like cells within adenoid cystic carcinoma. Macrophages with immunosuppressive properties dominate the immune microenvironment across subtypes. Responses to immunotherapy are limited and associated with a higher ratio of T-cells relative to macrophages in individual cases, warranting further investigation. Here, we show an immunosuppressive environment in salivary gland cancers and identify subtype-specific immune vulnerabilities that could inform tailored therapeutic strategies.

Advances in Targeted and Systemic Therapy for Salivary Gland Carcinomas: Current Options and Future Directions

Salivary gland carcinomas (SGCs) represent a rare and heterogeneous group of malignancies accounting for 3-6% of all head and neck cancers. While surgical resection and radiotherapy remain the standard for locoregional control, systemic treatment is indicated for recurrent or metastatic disease. Advances in molecular profiling have identified actionable targets such as NTRK gene fusions, HER2, immune checkpoint regulators, androgen receptors, and RET receptors. These have facilitated the development of targeted therapies, including TRK inhibitors, HER2-directed agents, and androgen receptor modulators, as well as emerging combinations of immunotherapy and chemotherapy. Despite these advancements, challenges such as resistance mechanisms and limited therapeutic efficacy persist. Overall response rates remain relatively low across most systemic therapies, reflecting a persistent unmet clinical need. This review discusses the current landscape of treatment options and explores promising clinical trials and future directions to enhance outcomes for patients with SGCs.

Response efficacy of PD-1 and PD-L1 inhibitors in salivary gland cancers: a systematic review and meta-analysis

Background

Salivary gland carcinoma (SGC) is an infrequent malignancy characterized by various pathological subtypes. Immune checkpoint inhibitors (ICIs) have emerged as promising therapeutic strategies for several cancers. Evidence suggests that ICIs may be effective against rare neoplasms, including SGC. This meta-analysis evaluated the efficacy of programmed death-1 (PD-1) and programmed death ligand 1 (PD-L1) inhibitors in treating salivary gland cancers.

Method

A thorough search was conducted in PubMed, Scopus, and Google Scholar databases up to 24 February 2024. The title, abstract, and full text of related articles were extracted and screened, and the quality of the included articles was assessed. The data extracted were then analyzed. The research protocol of this systematic review and meta-analysis was registered on the PROSPERO website.

Results

Altogether, a total of five cohort studies and three randomized controlled trials (RCTs) with a total population of 532 were included in these meta-analyses. These studies were conducted in the USA, Japan, France, and China. The average age of the patients was between 53 and 67 years. Our analyses showed an increase in progression-free survival in the cohort studies and RCTs, and the pooled effect is 1.12 (95% CI 1-1.25) and 1.14 (95% CI 1.07-1.20), respectively, in patients with SGC who received PD-1 and PD-L1 inhibitors.

Conclusion

This meta-analysis suggests that PD-1 and PD-L1 inhibitors in patients with salivary gland cancer can significantly increase progression-free survival. Due to the high heterogeneity of the studies, more RCTs with a larger sample size are required to prove the association.

Baseline (modified) Glasgow prognostic score as a predictor of therapeutic response to immune checkpoint inhibitors in solid tumors: A systematic review and meta‑analysis

A systemic analysis was performed to evaluate the prognostic utility of the Glasgow prognostic score (GPS) and the modified (m)GPS in cancer patients treated with immune checkpoint inhibitors (ICI). The PubMed, Cochrane Library, EMBASE and Google Scholar databases were searched for entries added until May 1st, 2023, to obtain relevant articles for this study. The analysis examined several clinical outcomes, including overall survival (OS), progression-free survival (PFS), objective response rate and disease control rate (DCR). In this analysis, a total of 38 articles with 3,772 patients were included. The pooled results indicated that patients with high GPS levels had shorter OS [GPS 2 vs. 0, hazard ratio (HR): 4.35, P<0.001; GPS 1 vs. 0, HR: 2.00, P<0.001; GPS 2 vs. 1/0, HR: 2.62, P<0.001; GPS 2/1 vs. 0, HR: 2.60, P<0.001) and PFS (GPS 2 vs. 0, HR: 2.11, P=0.001; GPS 1 vs. 0, HR: 1.33, P=0.001; GPS 2 vs. 1/0, HR: 2.11, P<0.001; GPS 2/1 vs. 0, HR: 1.62, P<0.001], as well as a lower DCR [GPS 2 vs. 1/0, odds ratio (OR): 0.53, P<0.001, GPS 2/1 vs. 0, OR: 0.51, P<0.001]. It was also found that patients with high mGPS levels had poorer OS (mGPS 2 vs. 0, HR: 3.15, P<0.001; mGPS 1 vs. 0, HR: 1.70, P<0.001; mGPS 2 vs. 1/0, HR: 1.95, P=0.049; mGPS 2/1 vs. 0, HR: 3.14, P=0.041; continuous variables, HR: 1.52, P<0.001) and PFS (mGPS 2 vs. 0, HR: 2.70, P<0.001; mGPS 1 vs. 0, HR: 1.74, P=0.016; mGPS 2 vs. 1/0, HR: 1.91, P=0.044; continuous variables, HR: 1.29, P<0.001), and lower DCR (mGPS 2 vs. 1/0, HR: 0.46, P<0.001). In conclusion, the GPS and mGPS were reliable predictors of outcomes in cancer patients treated with ICIs.

The Role of Immunotherapy in Salivary Gland Cancer: A Systematic Review

Background: Salivary gland cancer (SGC) comprises a very heterogeneous group of rare neoplasms, accounting for approximately 2% to 6% of head and neck malignancies. Surgery with or without adjuvant radiotherapy is the main treatment regimen. However, patients who are ineligible for surgery, including late-stage, recurrent, or metastatic disease, have very limited options. Chemotherapeutic schemes have failed to offer meaningful survival benefit, while the role of immune checkpoint inhibitors (ICIs) like anti-PD1, anti-PDL1, and anti-CTLA4 is largely unknown. Methods: A systematic database search of clinical trials evaluating the role of anti-PD1 and anti-CTLA4 immunotherapy in the survival of patients with SGC was conducted in EMBASE, MEDLINE, and Scopus databases. Primary outcomes were overall survival, progression-free survival, complete responses (CRs), partial responses (PRs), stable disease (SD), and objective response rates. Results: We identified 770 relevant studies. Nine clinical trials and 4 retrospective studies met the inclusion criteria and were eligible for further analysis. A total of 473 patients were studied, with an average age of 61 ± 4 years old for prospective trials and 60 ± 11 years old for retrospective studies. For studies that provided gender, the male-to-female ratio was 1.2:1 for prospective trials versus 4:1 for retrospective studies. All patients in the clinical trials had recurrent or metastatic disease. All patients received anti-PD1 ICI with either pembrolizumab or nivolumab, 7 study arms administering pembrolizumab, 10 study arms administering nivolumab. For prospective trials, 6/9 studies also reported an additional intervention. Most prevalent histology was adenoid cystic carcinoma (n = 230). Outcome of prospective trial were 1 CR, 19 PRs 145 SD, and 80% of patients reporting an adverse event (AE) of any grade. For retrospective studies, 1 patient reported CR, 3 patients reported PR, 11 patients reported SD, and 92% of patients reported an AE of any grade. Conclusion: Anti-PD1 immunotherapeutic modalities can be a safe and potentially-beneficial option for patients with advanced, recurrent, or metastatic SGC. However, the literature suffers from small cohorts, lack of randomization, and heterogeneity among different histologies of SGC. Prospective trials evaluating the role of anti-PD1 in patients with SGC, stratified by histology are warranted to determine the potential role of immunotherapy in the treatment of this disease.

Monocyte-related markers as predictors of immune checkpoint inhibitor efficacy and immune-related adverse events: a systematic review and meta-analysis

The efficacy and off-target effects of immune checkpoint inhibitors (ICI) in cancer treatment vary among patients. Monocytes likely contribute to this heterogeneous response due to their crucial role in immune homeostasis. We conducted a systematic review and meta-analysis to evaluate the impact of monocytes on ICI efficacy and immune-related adverse events (irAEs) in patients with cancer. We systematically searched PubMed, Web of Science, and Embase for clinical studies from January 2000 to December 2023. Articles were included if they mentioned cancer, ICI, monocytes, or any monocyte-related terminology. Animal studies and studies where ICIs were combined with other biologics were excluded, except for studies where two ICIs were used. This systematic review was registered with PROSPERO (CRD42023396297) prior to data extraction and analysis. Monocyte-related markers, such as absolute monocyte count (AMC), monocyte/lymphocyte ratio (MLR), specific monocyte subpopulations, and m-MDSCs were assessed in relation to ICI efficacy and safety. Bayesian meta-analysis was conducted for AMC and MLR. The risk of bias assessment was done using the Cochrane-ROBINS-I tool. Out of 5787 studies identified in our search, 155 eligible studies report peripheral blood monocyte-related markers as predictors of response to ICI, and 32 of these studies describe irAEs. Overall, based on 63 studies, a high MLR was a prognostic biomarker for short progression-free survival (PFS) and overall survival (OS) hazard ratio (HR): 1.5 (95% CI: 1.21-1.88) and 1.52 (95% CI:1.13-2.08), respectively. The increased percentage of classical monocytes was an unfavorable predictor of survival, while low baseline rates of monocytic myeloid-derived suppressor cells (m-MDSCs) were favorable. Elevated intermediate monocyte frequencies were associated but not significantly correlated with the development of irAEs. Baseline monocyte phenotyping may serve as a composite biomarker of response to ICI; however, more data is needed regarding irAEs. Monocyte-related variables may aid in risk assessment and treatment decision strategies for patients receiving ICI in terms of both efficacy and safety.

Immune-Modified Glasgow Prognostic Score Predicts Therapeutic Effect of Pembrolizumab in Recurrent and Metastatic Head and Neck Cancer

BACKGROUND

Previously, we proposed that the immune-modified Glasgow Prognostic Score (imGPS), which adds the lymphocyte count to the mGPS, is helpful as a prognostic marker for patients with head and neck squamous cell carcinoma. In this study, we investigated the imGPS as a marker for the therapeutic effect of pembrolizumab in treating recurrent and metastatic head and neck cancer (RMHNC).

METHODS

This study included RMHNC patients who were treated with pembrolizumab from December 2019 to April 2024. ALB, CRP, lymphocyte counts, neutrophil-to-lymphocyte ratios (NLRs), mGPSs, and imGPSs were extracted as biomarkers, and the response rate and prognosis were analyzed for each.

RESULTS

A total of 54 patients were enrolled. Lymphocyte counts were correlated with the overall response rates (ORRs) (p = 0.0082). Although the mGPS did not show significant differences in ORRs, imGPSs revealed a significant difference (p = 0.013). CRP, ALB, and lymphocyte counts were correlated with overall survival (OS) and/or progression-free survival (PFS). NLRs, mGPSs, and imGPSs were also correlated with OS and/or PFS, with imGPSs showing the greatest area under the curve (OS; AUC = 0.795, PFS; AUC = 0.754).

CONCLUSIONS

This study demonstrates that the imGPS is an excellent predictive marker for the therapeutic effect and prognosis of pembrolizumab for RMHNC. The imGPS can be employed with daily blood tests, highlighting the potential to forecast the impact of the ICI with high reliability.

Systemic treatments in recurrent or metastatic salivary gland cancer: a systematic review

BACKGROUND

Salivary gland cancers are infrequent and pose a challenge owing to their histological diversity and varied clinical behavior, making the selection of optimal systemic treatments for advanced or recurrent stages difficult. This systematic review aims to assess overall survival outcomes and systemic treatment responses across four types of salivary cancers.

METHODS

A PubMed and Google Scholar search identified studies involving initially advanced or relapsed cases undergoing systemic treatment. Studies with clear, individualized data on treatment responses and outcomes were selected based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. Of the 723 studies screened, 44 met our inclusion criteria.

RESULTS

A total of 426 cases of recurrent/metastatic salivary gland cancer, mostly salivary duct carcinoma (SDC; n = 219) and adenoid cyst carcinoma (ACC; n = 167), were included. Histomolecular markers were heavily associated with histology, with HER2 overexpression and androgen receptor nuclear expression typically found in SDC and adenocarcinoma not otherwise specified cases and KIT overexpression only in ACC. The response rates were associated with specific receptor blockage, with trastuzumab plus chemotherapy, and bicalutamide being the most effective (overall response rate 80% and 42.8%, respectively). Moreover, the response to treatment positively influenced overall survival (responders 38 versus non-responders 18.7 median months; P < 0.001). In this retrospective analysis of a particular cohort, survival outcomes per histology types showed that anti-human epidermal growth factor receptor 2 therapy was more effective for SDC, while chemotherapy was more effective for ACC.

CONCLUSION

Systemic treatments contribute to the survival of patients with salivary gland cancer at relapsed or newly advanced stages. The response to treatment is heavily influenced by histological subtype and treatment specificity.

Nivolumab as a Promising Treatment Option for Metastatic Salivary Duct Carcinoma

Salivary duct carcinomas (SDC) of the parotid gland are rarely occurring highly malignant tumors. A 65-year-old man presented with a preauricular mass. After surgical treatment and histologic examination, the findings were interpreted as a squamous cell carcinoma (SCC) metastasis of the parotid gland deriving from a cancer of unknown primary DD primary SCC of the parotid gland. Adjuvant platinum-based radiochemotherapy was administered in domo. However, re-staging revealed multiple size-progressive pulmonary round lesions. After resection and histological examination of a pulmonary mass and in synopsis with the primary tumor, the initial diagnosis of SCC was revised to SDC of the parotid gland. With positive HER-2 status, off-label trastuzumab/docetaxel was initiated in an individual healing attempt, during which the pulmonary metastases showed clear progression. Consequently, the patient received immunotherapy with nivolumab according to his negative PD-L1 status. After 57 cycles of nivolumab, the patient presents with partial remission and in good condition. We report, for the first time, a robust response of metastatic SDC to checkpoint inhibition with nivolumab without additional radiotherapy.

PD-L1 expression as a predictive biomarker in patients with recurrent or metastatic salivary gland carcinoma treated with pembrolizumab

Although immune checkpoint inhibitors (ICIs) are effective in some patients with salivary gland carcinoma (SGC), biomarkers which predict the efficacy and prognosis of SGC patients treated with pembrolizumab have not been identified. We conducted a multi-institutional retrospective cohort study to evaluate the efficacy and safety of pembrolizumab monotherapy in patients with recurrent and/or metastatic SGC and to determine optimal cut-off values of the combined positive score (CPS) and tumor proportion score (TPS) as numerical expression levels of programmed death-ligand 1 (PD-L1), which predict the efficacy of pembrolizumab. Furthermore, we investigated the association of patient characteristics and hematological markers with clinical outcomes, including overall response rate (ORR), progression-free survival (PFS), and overall survival (OS). From 2016 to 2021, 27 patients were included in the analysis. ORR of SGC was 25.9%. Optimal cut-off values of CPS and TPS were 15 and 25%, respectively. ORRs of CPS-high and TPS-high were 55.6 and 75.0%, respectively, and significantly higher than those of CPS-low and TPS-low. Furthermore, patients with a low platelet-lymphocyte ratio (PLR) had a significantly longer PFS. No grade 4 or greater adverse events were observed. This study demonstrated the efficacy and safety of pembrolizumab monotherapy and identified optimal cut-off values of CPS and TPS.

Exploring Immunological Effects and Novel Immune Adjuvants in Immunotherapy for Salivary Gland Cancers

Salivary gland cancer (SGC) is rare and comprises over 20 histological subtypes. Recently, clinical experience regarding immunotherapies for SGCs has been accumulating, yet their efficacy remains controversial. Understanding the tumor microenvironment (TME), including the expression of immune checkpoint molecules in SGC, is crucial to optimizing immunotherapy. In this review, we demonstrate that high-grade mucoepidermoid carcinoma and salivary duct carcinoma generally exhibit immune-hot TME with high immune cell infiltration, frequent genetic mutations, and robust immune checkpoint molecule expression. In contrast, adenoid cystic carcinomas exhibit an immune-cold TME. While the reported efficacy of immune checkpoint inhibitors (ICIs) for SGCs is generally poor, several studies showed promising clinical efficacy of ICIs, with an objective response rate ranging from 20.0-33.3%, indicating that ICIs might be beneficial for a specific population of SGC. Molecule-targeted therapies including anti-human epidermal growth factor receptor 2 and anti-androgen receptor therapies have shown promising clinical efficacy against SGC. Recent evidence indicates that these molecules could be targets for antigen-specific immunotherapies including chimeric antigen receptor-T therapy and cancer vaccines. This review discusses the current understanding and future directions of immunotherapies for SGCs, including ongoing clinical trials.

Salivary gland carcinoma: Towards a more personalised approach

Salivary Gland carcinomas (SGCs) are rare tumors accounting for less than 1% of all cancers with 21 histologically diverse subtypes. The rarity of the disease presents a challenge for clinicians to conduct large size randomized controlled trials. Surgery and radiotherapy remain the only curative treatment for localized disease, whereas treatments for recurrent and metastatic disease remain more challenging with very disappointing results for chemotherapy. The different histological subtypes harbor various genetic alterations, some pathognomonic with a diagnostic impact for pathologists in confirming a difficult diagnosis and others with therapeutic implications regardless of the histologic subtype. Current international guidelines urge pathologists to identify androgen receptor status, HER-2 expression that could be determined by immunohistochemistry, and TRK status in patients with non-adenoid cystic salivary gland carcinoma that are eligible to initiate a systemic treatment, in order to offer them available targeted therapies or refer them to clinical trials based on their mutational profile. A more advanced molecular profiling by next generation sequencing would offer a larger panel of molecular alterations with possible therapeutic implications such as NOTCH, PI3K, BRAF, MYB, and EGFR. In the following review, we present the most common genetic alterations in SGCs as well as actionable mutations with the latest available data on therapeutic options and upcoming clinical trials.

Translational Insights in the Landscape of Salivary Gland Cancers: Ready for a New Era?

Salivary gland carcinomas (SGCs) are rare neoplasms, representing less than 10% of all head and neck tumors, but they are extremely heterogeneous from the histological point of view, their clinical behavior, and their genetics. The guidelines regarding their treatment include surgery in most cases, which can also play an important role in oligometastatic disease. Where surgery cannot be used, systemic therapy comes into play. Systemic therapy for many years has been represented by polychemotherapy, but recently, with the affirmation of translational research, it can also count on targeted therapy, at least in some subtypes of SGCs. Interestingly, in some SGC histotypes, predominant mutations have been identified, which in some cases behave as "driver mutations", namely mutations capable of governing the carcinogenesis process. Targeting these driver mutations may be an effective therapeutic strategy. Nonetheless, it is not always possible to have drugs suitable for targeting driver mutations-and targeting driver mutations is not always accompanied by a clinical benefit. In this review, we will analyze the main mutations predominant in the various histotypes of SGCs.

Immunological subtyping of salivary gland cancer identifies histological origin-specific tumor immune microenvironment

Gene expression analysis enhances proper cancer subtyping, a better understanding of the molecular characteristics of cancer, and strategies for precision medicine. However, salivary gland cancer (SGC) subtyping remains largely unexplored because of its rarity and diverse histopathological and immunological characteristics. This study aimed to determine whether the histological origin and immunological characteristics of SGC subtypes are intrinsic tumor immunity factors. We performed immune profiling of 94 RNA-seq of SGC tissues and found that the SGCs that originated from the excretory duct (ED), such as the salivary duct and mucoepidermoid carcinomas, exhibit higher immunity than those from the intercalated duct (ID), such as the adenoid cystic and myoepithelial carcinomas, based on the computationally predicted immune score (p < 0.001), immune cell enrichment in the tumor immune microenvironment (TIME) (p < 0.001), T-cell receptor diversity (p < 0.001), and expression of signal I (major histocompatibility complex, MHC, p < 0.001) and signal II (co-stimulatory, p < 0.001 and co-inhibitory, p < 0.001) genes. Further analysis revealed that tolerogenic dendritic cell-induced dysfunctional T-cell populations and T-cell exclusion in the TIME are the major immune evasive mechanisms of the ED-and ID-derived SGCs, respectively.

The neutrophil-to-lymphocyte ratio in salivary gland cancers treated with pembrolizumab

BACKGROUND

A minority of patients with recurrent/metastatic (R/M) salivary gland cancers (SGCs) benefit from immune checkpoint inhibitors (ICIs), necessitating reliable biomarkers for ICI response prediction.

METHODS

Retrospective observational study of R/M SGC patients treated with pembrolizumab between 2016 and 2022, with a primary outcome of 6-month progression-free survival (PFS) and secondary outcome of 2-year overall survival (OS). Univariate and multivariable Cox proportional hazards models were employed.

RESULTS

Twenty R/M SGC patients were included. After adjustment, NLR as a continuous variable was independently associated with 6-month PFS (HR 1.30, 95% CI 1.10-1.54, p = 0.002) and 2-year OS (HR 1.33, 95% CI 1.07-1.66, p = 0.010). Similarly, NLR ≥ 5 was associated with higher hazards of progression at 6 months (HR 12.85, 95% CI 2.17-76.16, p = 0.005) and death at 2 years (HR 11.25, 95% CI 1.67-75.77, p = 0.013).

CONCLUSIONS

Higher pretreatment NLR was independently associated with inferior 6-month PFS and 2-year OS in pembrolizumab-treated R/M SGC patients.

A systematic review and meta-analysis of prognostic indicators in patients with head and neck malignancy treated with immune checkpoint inhibitors

INTRODUCTION

Tumor immunotherapy has recently emerged as a crucial focal point in oncology treatment research. Among tumor immunotherapy approaches, tumor immune checkpoint inhibitors (ICIs) have attracted substantial attention in clinical research. However, this treatment modality has benefitted only a limited number of patients. We conducted a meta-analysis of various biomarkers to decipher their prognostic implications in patients with head and neck squamous cell carcinoma (HNSCC) who are treated with ICIs, and thus identify predictive markers with practical clinical relevance.

METHODS

A systematic search of electronic databases was conducted to identify clinical studies that examined the correlation between biomarkers and treatment outcomes in the HNSCC patients. The included articles were screened and analyzed to extract data regarding overall survival (OS) and progression-free survival (PFS).

RESULTS

The relationship between the biomarkers included in the summary and prognosis was as follows: HPV positivity was associated with improved OS (HR = 0.76, 95% CI = 0.58-1.99), PFS (HR = 1.16, 95% CI = 0.81-1.67), and response (OR = 1.67, 95% CI = 1.37-2.99). PD-L1 positivity was associated with OS (HR = 0.71, 95% CI = 0.59-0.85), PFS (HR = 0.56 95% CI = 0.43-0.73), and response (OR = 2.16, 95% CI = 1.51-3.10). Neither HPV positivity nor PD-L1 positivity was associated with DCR. The following markers were collected for OS and PFS data and were associated with longer OS: lower Glasgow prognostic score (GPS/mGPS) grading, lower PS grading, high body mass index (BMI), low neutrophil-to-lymphocyte ratio (NLR), low platelet-to-lymphocyte ratio (PLR), high albumin (Alb), low lactate dehydrogenase (LDH). Factors associated with better PFS were lower GPS/mGPS grading, lower PS grading, high BMI, low NLR, high absolute lymphocyte count, and low LDH. Hyperprogressive disease was associated with worse OS and PFS. Fewer clinical studies have been completed on the tumor microenvironment and hypoxia, microsatellite instability/DNA mismatch repair, and microbiome and systematic analysis is difficult.

CONCLUSION

In our meta-analysis, different immune checkpoint factors were associated with different prognoses in HNSCC patients receiving immunotherapy. HPV, PD-L1, BMI, Alb, HPD, PS, GPS/mGPS, LDH, NLR, and PLR predicted the ICI outcome in HNSCC patients.

Current management and future challenges in salivary glands cancer

Salivary gland cancers (SGCs) are rare, accounting for less than 5% of all malignancies of the head and neck region, and are morphologically heterogeneous. The diagnosis is mainly based on histology, with the complementary aid of molecular profiling, which is helpful in recognizing some poorly differentiated, borderline, or atypical lesions. Instrumental imaging defines the diagnosis, representing a remarkable tool in the treatment plan. Ultrasound and magnetic resonance are the most common procedures used to describe the primary tumour. The treatment of SGCs is multimodal and consists of surgery, radiotherapy, and systemic therapy; each treatment plan is, however, featured on the patient and disease's characteristics. On 24 June 2022, in the meeting "Current management and future challenges in salivary gland cancers" many experts in this field discussed the state of the art of SGCs research, the future challenges and developments. After the meeting, the same pool of experts maintained close contact to keep these data further updated in the conference proceedings presented here. This review collects the insights and suggestions that emerged from the discussion during and after the meeting per se.

A Case of Metastatic Submandibular Salivary Duct Carcinoma that Completely Responded to Pembrolizumab Monotherapy

Salivary gland carcinoma is a rare cancer and has more than 20 histopathological types. Although chemotherapy has been the mainstay of treatment for unresectable carcinomas such as multiple recurrence and distant metastasis, no standard regimen is available. In this article, we report a case of poorly differentiated salivary duct carcinoma of the submandibular gland with distant metastases that was successfully treated with pembrolizumab monotherapy. A 66-year-old man became aware of a left submandibular mass 2 months before his first visit to our department. A needle biopsy at a previous hospital revealed carcinoma, not otherwise specified. The combined positive score on a programmed death ligand-1 immunohistochemistry test was 1-10%. The patient was referred to our department for further treatment. Computed tomography revealed left level II and IV neck lymphadenopathy, bilateral lung shadowing, and osteolytic changes in the 12th thoracic vertebra. Needle biopsy showed poorly differentiated carcinoma, positive human epidermal growth factor receptor 2, and positive androgen receptor, which suggested salivary duct carcinoma. These findings indicated a diagnosis of submandibular carcinoma T4aN2bM1 stage IVC. Pembrolizumab monotherapy was started, and tumor shrinkage was observed after three courses of treatment. At 1 year, complete response was achieved without adverse events, and treatment is ongoing. Despite a lack of evidence for the efficacy of immune checkpoint inhibitors in salivary gland carcinoma, the present case suggests that some patients might respond to this treatment. Hence, clinical trials are warranted.

Prognostic value and clinicopathological roles of the tumor immune microenvironment in salivary duct carcinoma

Salivary duct carcinoma (SDC) is an aggressive type of salivary gland carcinoma. Recently, immunotherapies targeting immune checkpoints, including PD1, PD-L1, CTLA4, and LAG3, have had a considerable prognostic impact on various malignant tumors. The implementation of such immune checkpoint inhibitor (ICI) therapies has also been attempted in cases of salivary gland carcinoma. The tumor immune microenvironment (TIME) is implicated in tumorigenesis and tumor progression and is closely associated with the response to ICI therapies. However, the TIME in SDC has not been fully explored. We examined the immunohistochemical expression of CD8, FOXP3, PD1, PD-L1, CTLA4, LAG3, and mismatch repair (MMR) proteins, tumor-infiltrating lymphocytes (TILs), and microsatellite instability (MSI) status in 175 cases of SDC. The associations between these TIME-related markers and the clinicopathological factors and prognosis were evaluated. An elevated expression of CD8, FOXP3, PD1, CTLA4, and LAG3 was associated with more aggressive histological features and an advanced N and/or M classification, elevated Ki-67 index, and poor prognosis. Furthermore, cases with a high PD-L1 expression exhibited more aggressive histological features and adverse clinical outcomes than those with a low expression. Alternatively, there was no significant correlation between TILs and clinicopathological factors. No SDC cases with an MSI-high status or MMR deficiency were found. The coexistence of both an immunostimulatory and immunosuppressive TIME in aggressive SDC might play a role in the presence of T-cell exhaustion. The contribution of multiple immune escape pathways, including regulatory T cells and immune checkpoints, may provide a rationale for ICI therapy, including combined PD1/CTLA4 blockade therapy.

Pituitary metastasis of salivary gland carcinoma mimicking hypophysitis: A case report and literature review

INTRODUCTION

Pituitary metastases from salivary gland carcinomas are rare. Moreover, pituitary metastasis and hypophysitis exhibit neuroimaging similarities that complicate the diagnosis in patients receiving immune checkpoint drugs.

PRESENTATION OF CASE

We present a case of pituitary metastasis derived from a sublingual gland carcinoma; this case posed a challenge in the differential diagnosis of hypophysitis. A 52-year-old male patient presented with anorexia and visual disturbances. The patient was previously diagnosed with sublingual gland carcinoma that necessitated surgical intervention consisting of tumor resection and residual lymph node dissection. Subsequently, the patient underwent immune checkpoint blockade therapy following platinum-based chemotherapy. Magnetic resonance imaging revealed the presence of an intrasellar tumor infiltrating the dura mater, cavernous sinus, and pituitary stalk with isointensity on T1 and T2 weighted images and homogeneous gadolinium enhancement. Despite the initial suspicion of hypophysitis, diagnostic treatment with systemic corticosteroids failed to induce significant tumor reduction. Diagnostic clarification was achieved via an endoscopic transsphenoidal biopsy, which confirmed the histological diagnosis of pituitary metastasis from the prior sublingual gland adenocarcinoma. Radiotherapy was administered as a therapeutic intervention.

DISCUSSION

The case report highlighted the rarity of metastases from salivary gland carcinoma to the pituitary gland and emphasized the challenges in distinguishing between pituitary metastasis and hypophysitis based on imaging studies alone, particularly in patients receiving immune checkpoint inhibitors.

CONCLUSION

Given the rarity of this condition and its neuroimaging similarities with hypophysitis, pathological confirmation is imperative for a definitive diagnosis.

The expression profiles of CD47 in the tumor microenvironment of salivary gland cancers: a next step in histology-driven immunotherapy

BACKGROUND

Salivary gland carcinomas (SGC) are extremely rare malignancies with only limited treatment options for the metastatic phase of the disease. Treatment with anti-CD47 antibodies could represent a potent therapy for SGCs by promoting the phagocytic clearance of tumor cells through various mechanisms. However, the efficacy of anti-CD47 therapy is largely dependent on the expression of CD47 within the tumor microenvironment (TME).

MATERIALS AND METHODS

In 43 patients with SGC, we were the first to investigate the CD47 expression in both tumor cells and tumor-infiltrating immune cells (TIIC) in the center and periphery of primary tumors. We also correlated the data with the clinicopathological variables of the patients and offered novel insights into the potential effectiveness of anti-CD47 therapy in SGCs.

RESULTS

We observed that the CD47⁺ tumor cells are outnumbered by CD47⁺ TIICs in mucoepidermoid carcinoma. In the tumor center, the proportion of CD47⁺ tumor cells was comparable to the proportion of CD47⁺ TIICs in most histological subtypes. In low-grade tumors, significantly higher expression of CD47 was observed in TIICs in the periphery of the tumor as compared to the center of the tumor.

CONCLUSION

The reason for a high expression of 'don't eat me' signals in TIICs in the tumor periphery is unclear. However, we hypothesize that in the tumor periphery, upregulation of CD47 in TIICs could be a mechanism to protect newly recruited leukocytes from macrophage-mediated phagocytosis, while also allowing the removal of old or exhausted leukocytes in the tumor center.

Survival benefit of HER2-targeted or androgen deprivation therapy in salivary duct carcinoma

Background

The efficacy and safety of human epidermal growth factor receptor 2 (HER2)-targeted therapy and androgen deprivation therapy (ADT) for locally advanced or recurrent or metastatic (LA/RM) salivary duct carcinoma (SDC) have been reported in prospective studies. However, the survival benefit of these therapies to conventional therapy remains controversial, and whether HER2-targeted therapy or ADT should be chosen in HER2- and androgen receptor (AR)-positive SDC patients remains unknown.

Methods

Overall, 323 LA/RM SDC patients treated at seven institutions between August 1992 and June 2020 were retrospectively enrolled. The primary aim was to analyze the effect of HER2-targeted therapy and ADT on overall survival from the diagnosis of LA/RM disease to death from any cause (OS1). The secondary indicators included the overall response rate (ORR), clinical benefit rate (CBR), overall survival from therapy initiation for LA/RM disease (OS2), progression-free survival (PFS), time to second progression (PFS2), duration of response (DoR), and duration of clinical benefit (DoCB) of HER2-targeted therapy or ADT as first-line therapy for HER2-positive/AR-positive SDC.

Results

Patients treated with HER2-targeted therapy or ADT had longer OS1 than those treated without these therapies (Median OS1: historical control, 21.6 months; HER2-targeted therapy, 50.6 months; ADT, 32.8 months; HER2-targeted therapy followed by ADT, 42.4 months; and ADT followed by HER2-targeted therapy, 45.2 months, p < 0.001). Among HER2-positive/AR-positive SDC patients, although HER2-targeted therapy had better ORR, CBR, and PFS than those of ADT as first-line therapy, we found no significant differences between HER2-targeted therapy and ADT regarding OS2, PFS2, DoR, and DoCB.

Conclusion

Patients treated with HER2-targeted therapy and ADT showed longer survival in LA/RM SDC. HER2-targeted therapy can be recommended prior to ADT for HER2-positive/AR-positive SDC. It is warranted to establish a biomarker that could predict the efficacy of clinical benefit or better response in ADT.

Efficacy of Immunotherapy Combined with Antiangiogenic Therapy in Treatment-Failure Patients with Advanced Carcinoma Ex Pleomorphic Adenoma of the Submandibular Gland: A Case Report

Carcinoma ex pleomorphic adenoma (Ca ex PA) is a rare malignant tumor that arises from a primary or recurrent benign pleomorphic adenoma (PA). Ca ex PA has an aggressive behavior and poor prognosis. To date, there are no standardized therapeutic methods. Herein, we reported a case of a 57-year-old Chinese female with Ca ex PA of the submandibular gland. After surgery, cervical lymph nodes recurred, and multiple distant metastases were detected. During the treatment, she received multiple chemotherapies and radiotherapy but suffered from multidrug resistance and repeated disease progression. Hence, PD-1 inhibitor (sintilimab), in combination with anlotinib, was administered, which resulted in better control of pulmonary metastases compared to the other treatment regimens. This provided an alternative treatment option for Ca ex PA of the submandibular gland patients with failed multiple therapies.

Prognostic role of PD-L1 expression in patients with salivary gland carcinoma: A systematic review and meta-analysis

Background

Although programmed cell death-ligand 1 (PD-L1) has been recognized as a potential marker in several cancers, the relationship between PD-L1 expression and survival in patients with salivary gland carcinoma (SGC) has remained unclear. We aimed to evaluate the association of PD-L1 expression with clinicopathological features and prognosis in SGC patients.

Methods

The databases Ovid Medline, PubMed, Scopus, and EMBASE were searched for relevant studies that detected PD-L1 expression in SGC. The meta-analysis was performed according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA), and the reporting recommendations for tumor marker prognostic studies (REMARK) was used to assess the quality of research eligible for this meta-analysis. Included studies were assessed using the Quality in Prognosis Studies (QUIPS) tool. Odds ratios (ORs) with 95% confidence interval (CI) were calculated to estimate the correlation between PD-L1 expression and clinicopathological features. Hazard ratios (HRs) with 95% CI were applied to assess the association between PD-L1 expression and survival outcomes of patients.

Results

A total of ten studies (including 952 patients with SGC) were evaluated. The meta-analysis showed that positive PD-L1 expression in SGC was significantly associated with male patients, older age, Tumor stage, lymph node metastasis, high pathological grade, and non-adenoid cystic carcinoma subtype. The pooled data demonstrated that high PD-L1 expression was associated with poor overall survival and disease-free survival. There was no significant correlation between PD-L1 expression and progression-free survival or disease-specific survival of SGC patients.

Conclusion

According to the meta-analysis, positive PD-L1 expression may play an important role as an effective marker of poor prognosis in patients with SGC. However, large-scale, prospective investigations are still needed to confirm the findings. The assessment of PD-L1 expression may aid in the personalized management of SGC.

A comprehensive analysis of Glasgow Prognostic Score (GPS)/the modified Glasgow Prognostic Score (mGPS) on immune checkpoint inhibitor efficacy among patients with advanced cancer

BACKGROUND

The association between Glasgow Prognostic Score (GPS) and the modified Glasgow Prognostic Score (mGPS) and clinical outcomes in patients receiving immune checkpoint inhibitors (ICIs) remains controversial. Thus, this meta-analysis aimed to examine the prognostic performance of GPS and mGPS in patients treated with ICIs.

METHODS

Eligible studies were retrieved from searches of EMBASE, PubMed, Web of Science, and Cochrane Library until July 2021. The hazard ratio (HR) and 95% confidence intervals (CIs) were pooled by using fixed-effect or random-effects model to evaluate the influence of GPS/mGPS on overall survival (OS) and progression-free survival (PFS).

RESULTS

A total of 1164 patients were included. Overall, mGPS score of 2 and 1 were related to inferior OS (p < 0.001) and PFS (p < 0.001). Subgroup analyses showed no significant association between mGPS score of 1 and OS in patients with non-small cell lung cancer (NSCLC), while this score was significantly associated with poor PFS in patients with NSCLC and head and neck squamous cell carcinoma. Higher GPS (score of 1 or 2) were associated with poor clinical outcomes (OS: p < 0.001; PFS: p = 0.036). Subgroup analysis showed high GPS levels were linked to worse OS in patients with NSCLC and gastric cancer, but not for PFS in these patients. Regarding test time point, GPS was related to worse OS and PFS in pre-treatment GPS group, but not in post-treatment GPS group.

CONCLUSION

GPS and mGPS showed great potential to predict survival in patients treated with ICIs. Large and perspective trial are warranted to further validate these findings.

The Predictive Potential of the Baseline C-Reactive Protein Levels for the Efficiency of Immune Checkpoint Inhibitors in Cancer Patients: A Systematic Review and Meta-Analysis

Background

The relationship between baseline C-reactive protein (CRP) level and the prognosis of cancer patients receiving immune checkpoint inhibitor (ICI) treatment remains controversial. The aim of this meta-analysis was to clarify whether baseline CRP level can serve as a biomarker to predict the efficiency of ICI therapy.

Methods

All associated articles published in the Cochrane Library, EMBASE, and PubMed databases from the inception of the database to December 30, 2021, were retrieved. Progression-free survival (PFS) and overall survival (OS) outcomes were meta-analyzed using the random-effects model and adjusted using the trim-and-fill method because of publication bias.

Results

Thirty-three studies (6,124 patients) conducted between 2013 and 2021 were identified. The pooled outcomes implied that high baseline CRP level patients had significantly worse OS (adjusted pooled value for univariate and multivariate analysis outcomes: HR = 1.48, 95% CI = 1.41-1.56; HR = 1.46, 95% CI = 1.34-1.59) and PFS (adjusted pooled value for univariate and multivariate analysis outcomes: HR = 1.29, 95% CI = 1.15-1.45; HR = 1.20, 95% CI = 1.02-1.40) than low baseline CRP level patients, irrespective of cancer or ICI type. Further analysis indicated that 1 mg/dl was appropriate as a cutoff value for determining the low or high level of baseline CRP to predict the OS or PFS of cancer patients receiving ICI treatment (univariate analysis: HR = 1.56, 95% CI = 1.24-1.97, P = 0.909; multivariate analysis: HR = 1.58, 95% CI = 1.23-2.03, P = 0.521).

Conclusions

High baseline CRP level (>1 mg/dl) may be an indicator for worse OS and PFS of cancer patients treated with ICIs. More high-quality prospective studies are warranted to assess the predictive value of CRP for ICI treatment.

Systemic therapy for salivary gland malignancy: current status and future perspectives

Salivary gland malignancies are rare neoplasms that have a broad histological spectrum and a variety of biologic behaviors. Salivary gland malignancies are known as chemo-resistant tumors, which render optimal treatment challenging. This review summarizes the role of systemic therapy for salivary gland malignancies. To date, the advantage of adding concurrent chemotherapy has remained undefined for both postoperative and inoperable locally advanced salivary gland malignancy patients undergoing radiotherapy. For recurrent/metastatic disease, local and/or systemic treatment options should be discussed in a multidisciplinary setting with consideration to both patient needs and tumor factors. For symptomatic patients or those who may compromise organ function, palliative systemic therapy can be a reasonable option based on the results of phase II studies. Platinum combination regimens as first-line therapy have been widely accepted. Personalized therapies have become established options, particularly for androgen receptor-positive, HER2-positive and NTRK fusion-positive salivary gland malignancies (i.e. androgen receptor and HER2 in salivary duct carcinoma and NTRK3 in secretory carcinoma). For patients with adenoid cystic carcinoma, multi-targeted tyrosine kinase inhibitors have also been developed. Anti-PD1 checkpoint inhibitors have shown limited activity to date. Investigation of active systemic treatments for salivary gland malignancy remains a significant unmet need. Future directions might include a more comprehensive genomic screening approach (usually next-generation sequencing-based) and combination strategies using immune checkpoint inhibitors. These are rare malignancies that require ongoing effort in the conduct of high-quality clinical trials.

Immunotherapy in head and neck squamous cell carcinoma and rare head and neck malignancies

The dismal prognosis of recurrent/metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) prompted recent advances in the field of therapeutic approaches beyond cytotoxic cancer therapy. In recent years, the deeper and increasing knowledge on the genomic landscape and the upcoming new data on immunotherapy enacted by HNSCCs have led to successful therapeutic targeting of the immune system. Immune checkpoint inhibitors (ICIs) have changed state of the art in R/M patients and could have a potential role even in early disease. The purpose of this work is to summarize the role of immunotherapy for R/M HNSCC in clinical practice, with insights about future perspectives. Updated immunotherapy results in other R/M head and neck cancers such as thyroid, salivary glands, nasopharynx, sinonasal cancers, and nuclear protein in testis (NUT) are presented.

Novel Prognostic Score for recurrent or metastatic head and neck cancer patients treated with Nivolumab

Although several prognostic factors in nivolumab therapy have been reported in recurrent or metastatic head and neck cancer (RM-HNC) patients, these factors remain controversial. Here, we conducted a multicenter retrospective cohort study to investigate the impact of clinico-hematological factors on survival in RM-HNC patients treated with nivolumab. We reviewed 126 RM-HNC patients from seven institutes. We evaluated the prognostic effects of clinico-hematological factors on survival. The median overall survival (OS) was 12.3 months, and the 1 year-OS rate was 51.2%. Patients without immune-related adverse events, lower relative eosinophil count, worse best overall response, higher performance status, and higher modified Glasgow Prognostic Score had worse survival. The score, generated by combining these factors, was associated with survival. Patients with score of 4-5 had worse survival than those with score of 2-3 and 0-1 [adjusted HR for PFS: score of 4-5, 7.77 (3.98-15.15); score of 2-3, 3.44 (1.95-6.06), compared to score of 0-1], [adjusted HR for OS: score of 4-5, 14.66 (4.28-50.22); score of 2-3, 7.63 (2.29-25.37), compared to score of 0-1]. Our novel prognostic score utilizing clinico-hematological factors might be useful to establish an individual treatment strategy in RM-HNC patients treated with nivolumab therapy.

Anticancer Effects of Sublingual Type I IFN in Combination with Chemotherapy in Implantable and Spontaneous Tumor Models

Salivary gland tumors are a heterogeneous group of neoplasms representing less than 10% of all head and neck tumors. Among salivary gland tumors, salivary duct carcinoma (SDC) is a rare, but highly aggressive malignant tumor resembling ductal breast carcinoma. Sublingual treatments are promising for SDC due to the induction of both local and systemic biological effects and to reduced systemic toxicity compared to other administration routes. In the present study, we first established that the sublingual administration of type I IFN (IFN-I) is safe and feasible, and exerts antitumor effects both as monotherapy and in combination with chemotherapy in transplantable tumor models, i.e., B16-OVA melanoma and EG.7-OVA lymphoma. Subsequently, we proved that sublingual IFN-I in combination with cyclophosphamide (CTX) induces a long-lasting reduction of tumor mass in NeuT transgenic mice that spontaneously develop SDC. Most importantly, tumor shrinkage in NeuT transgenic micewas accompanied by the emergence of tumor-specific cellular immune responses both in the blood and in the tumor tissue. Altogether, these results provide evidence that sublingual IFN holds promise in combination with chemotherapy for the treatment of cancer.

Real-World, Long-Term Outcomes of Nivolumab Therapy for Recurrent or Metastatic Squamous Cell Carcinoma of the Head and Neck and Impact of the Magnitude of Best Overall Response: A Retrospective Multicenter Study of 88 Patients

Simple Summary

No real-world, long-term outcomes of immunotherapy with nivolumab for recurrent or metastatic squamous cell carcinoma of the head and neck (R/M SCCHN) have yet been reported. Furthermore, the prognostic impact of the best overall response (BOR) of this therapy remains unclear. We conducted a multi-institutional cohort study of the long-term efficacy and safety of this therapy. We also evaluated the relationship between BOR and survival. Median follow-up time was 25.9 months. Median overall survival (OS) was 9.6 months, and two-year survival rate was 25.0%. Overall response rate was 18%, and disease control rate was 48%. For immune-related adverse events (irAEs), 38 irAEs were detected in 29 patients. The development of irAEs and better BOR were significantly associated with longer survival. These findings demonstrate the long-term efficacy and safety of nivolumab therapy for R/M SCCHN in a real-world setting. The magnitude of BOR and the development of irAEs might be useful surrogate markers of survival.

Abstract

No real-world, long-term outcomes of immunotherapy with nivolumab for recurrent or metastatic squamous cell carcinoma of the head and neck (R/M SCCHN) have yet been reported. Furthermore, the prognostic impact of the best overall response (BOR) of this therapy remains unclear. We conducted a multi-institutional cohort study of the long-term efficacy and safety of this therapy and investigated prognostic factors associated with survival. Further, we evaluated the relationship between BOR and survival. Median follow-up time was 25.9 months. Median overall survival (OS) was 9.6 months, and two-year survival rate was 25.0%. Median progression-free survival (PFS) was 3.7 months, and two-year PFS rate was 19.6%. BOR was assessed as complete response (CR) in 6%, partial response (PR) in 13%, stable disease (SD) in 30%, and progressive disease (PD) in 52% of the patients. Overall response rate was 18%, and disease control rate was 48%. For immune-related adverse events (irAEs), 38 irAEs were detected in 29 patients. On multivariate analysis, the development of irAEs was significantly associated with better OS and PFS. Better BOR was significantly associated with longer OS and PFS. These findings demonstrate the long-term efficacy and safety of nivolumab therapy for R/M SCCHN in a real-world setting. The magnitude of BOR and the development of irAEs might be useful surrogate markers of survival.