Systemic therapy in the management of metastatic or locally recurrent adenoid cystic carcinoma of the salivary glands: a systematic review

Treatment strategies and prognostic insights for lacrimal gland adenoid cystic carcinoma: a review

Adenoid cystic carcinoma (ACC) is the most common type of malignant tumor in lacrimal gland cancer. The primary treatment approach involves eye-preserving surgery combined with adjuvant radiotherapy, which has proven effective in maintaining visual function and achieving favorable local control with minimal toxicity. However, the 5-year survival rate for ACC of the lacrimal gland remains below 60%. Recently, novel adjuvant therapies, including neoadjuvant intra-arterial chemotherapy, proton radiotherapy, and neutron radiotherapy, have significantly improved survival outcomes. Despite these advances, the rarity of lacrimal gland adenoid cystic carcinoma (LGACC) limits comprehensive studies on long-term survival and the potential for late toxicity, underscoring the need for further research. Additionally, recent findings on pathogenic mechanisms and proteomic abnormalities in LGACC offer a foundation for developing targeted therapies, paving the way for more personalized treatments. This article reviews contemporary treatment strategies and prognostic insights for LGACC, focusing on recent advancements and their implications for patient survival.

Efficacy of Eribulin Monotherapy in Patients With Unresectable and/or Metastatic Adenoid Cystic Carcinoma Receiving Platinum-Based Therapy

BACKGROUND

Adenoid cystic carcinoma (ACC) is the second most common and treatment-resistant salivary gland carcinoma (SGC). Although platinum-based therapies are effective, the efficacy of eribulin, a microtubule inhibitor with an 18% response rate in a Phase II trial involving recurrent/metastatic SGC, in patients with advanced ACC after platinum therapy remains unclear.

METHODS

We retrospectively analyzed 19 patients with unresectable/metastatic ACC treated with platinum-based therapy between December 2015 and January 2023 at the National Cancer Center Hospital, Japan. Ten patients received eribulin.

RESULTS

The median age was 61 years. 84% achieved disease control with the first-line or later platinum-based therapy (median progression-free survival [mPFS]: 7.6 months). Second-line or later eribulin monotherapy yielded a 50% disease control rate, with mPFS of 3.7 months and median overall survival of 41.7 months. The adverse events, predominantly neutropenia, were manageable.

CONCLUSION

Eribulin shows promising effects of unresectable/metastatic ACC, offering tolerable adverse events.

A novel model for predicting prognosis in patients with metastatic major salivary gland carcinoma

BACKGROUND

Patients with metastatic major salivary gland carcinoma (SGCs) always end with a poor prognosis, and survival time is a major concern for clinicians and patients, but effective predictive tools are lacking in clinical practice.

METHODS

Clinical information on patients diagnosed with metastatic major SGCs was extracted from the SEER database. Cox analysis was applied to identify clinicopathological characteristics associated with patient overall survival (OS). A random survival forest (RSF) algorithm was used to establish an accurate prognostic prediction model for these patients.

RESULTS

Cox analysis revealed that age, T stage, N stage, pathology type, bone and liver metastasis, primary tumor surgery, chemotherapy, and radiotherapy were independent factors for OS among patients with metastatic major SGCs. Our RSF model has a C-index of 0.657 in the test set and 0.701 in the external validation set, and the area under the curve (AUC) values at 1, 3, and 5 years range from 0.715-0.802 in the test set and 0.655-0.918 in the external validation set. Patients were divided into high-risk and low-risk groups based on the risk score of the RSF model, and patients in the low-risk group had significantly better OS than those in the high-risk group, and chemotherapy did not benefit patients in the low-risk group.

CONCLUSION

In this study, a prognostic prediction model was constructed for patients with metastatic major SGCs using RSF algorithm, and the validation results indicate that the model has the potential to be a useful tool for clinicians in predicting survival and designing individualized treatment.

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.

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.

Durvalumab and tremelimumab in patients with advanced rare cancer: a multi-centre, non-blinded, open-label phase II basket trial

Background

Dual inhibition of cytotoxic T-lymphocyte associated protein 4 (CTLA-4) and programmed death ligand 1 (PD-L1) has been shown to be an effective treatment strategy in many cancers. We sought to determine the objective response rate of combination durvalumab (D) plus tremelimumab (TM) in parallel cohorts of patients with carefully selected rare cancer types in which these agents had not previously been evaluated in phase II trials and for which there was clinical or biological rationale for dual immune checkpoint inhibitor therapy to be active.

Methods

We designed a multi-centre, non-blinded, open-label phase II basket trial with each of the following 8 rare cancers considered a separate phase II trial: salivary carcinoma, carcinoma of unknown primary (CUP) with tumour infiltrating lymphocytes and/or expressing PD-L1, mucosal melanoma, acral melanoma, osteosarcoma, undifferentiated pleomorphic sarcoma, clear cell carcinoma of the ovary (CCCO) or squamous cell carcinoma of the anal canal (SCCA). The primary objective was to evaluate the response rate of the combination of D and TM, and the secondary objectives were to evaluate the tolerability and safety of D and TM combination. Eligible patients had advanced, metastatic or recurrent, or unresectable cancer with no known life-prolonging treatment option, age ≥16 years, ECOG performance status 0 or 1. Patients received D (1500 mg IV) + TM (75 mg IV) on Day 1 q4 weeks for 4 cycles followed by D q4 weeks until disease progression. This trial is registered with ClinicalTrials.gov, NCT02879162.

Findings

From December 14th, 2016, to August 14, 2019, 140 patients enrolled into seven cohorts. The rare melanoma cohorts were closed due to lack of accrual. Of the 140 patients enrolled, 138 were eligible, 138 were evaluable for toxicity and 128 (91%) were evaluable for response. Durable responses were noted in all cohorts except for osteosarcoma. The overall response rate for eligible patients was 16% (95% CI: 10-23%). The response rates in each cancer cohort were undifferentiated pleomorphic sarcoma 15% (n = 3/20; 95% CI 3-38%), salivary carcinoma 20% (n = 4/20; 95% CI: 6-44%), CUP 17% (n = 3/18; 95% CI 4-41%), SCCA 10% (n = 2/20; 95% CI 12-32%) and CCCO 21% (n = 8/39; 95% CI 9-37%). Grade 3/4 adverse events were rare, where 4 patients experienced grade 4 related events and39 patients experienced grade 3 events.

Interpretation

Durvalumab + tremelimumab treatment resulted in meaningful responses in salivary carcinoma and CCCO and deserves further exploration in front-line studies.

Funding

AstraZeneca and Canadian Cancer Society.

Recurrence after primary salivary gland carcinoma: Frequency, survival, and risk factors

BACKGROUND

Primary salivary gland carcinomas (SGC) are rare neoplasms that present therapeutic challenges especially in recurrent tumors. The aim of this study was to investigate the incidence and distribution of tumor recurrence, associated risk factors, and survival.

METHODS

This analysis includes data from 318 patients treated for SGC between 1992 and 2020. Survival analysis was performed using the Kaplan-Meier method. Univariate and multivariate analyses were used to identify risk factors associated with recurrence.

RESULTS

21.7% of the patients developed recurrent disease after a mean of 38.2 months. In multivariate analysis, positive-resection margins, vascular invasion, and tumor localization in the submandibular gland and small salivary glands were independent factors for recurrence. The 5-year overall survival was 67%, the 5-year disease-free survival was 54%.

CONCLUSION

Tumor recurrence in SGC occurred in one out of five patients. In highly aggressive entities and patients with risk factors, treatment intensification should be considered.

Salivary adenoid cystic carcinoma-derived α2,6-sialylated extracellular vesicles increase vascular permeability by triggering ER-stress in endothelial cells and promote lung metastasis

Salivary adenoid cystic carcinoma (SACC) tends to metastasize to the lungs in the early stages of the disease. Factors secreted by the primary tumor can induce the formation of a supportive microenvironment in distant organs prior to metastasis, a process known as pre-metastatic niche (PMN) formation. Extracellular vesicles (EVs) participate in PMN formation. In this study, α2,6-sialylation of EVs derived from SACC cells with high metastatic potential increased vascular permeability, thereby facilitating tumor metastasis to the lungs. Mechanistic studies indicated that EV α2,6-sialylation triggers protein kinase R-like endoplasmic reticulum kinase (PERK)-eukaryotic initiation factor 2α (eIF2α)-dependent activation of endoplasmic reticulum (ER) stress in the endothelium, leading to the disruption of vascular endothelial cadherin membrane expression. Sialidase or an ER stress inhibitor rescued vascular permeability induced by SACC EVs, which decreased the number of SACC cells extravasating into the lungs both in vitro and in vivo. This study identified a critical role of α2,6-sialylation of SACC EVs in lung metastasis. The findings indicate that EV α2,6-sialylation-induced ER stress in endothelial cells might be a therapeutic target for preventing SACC lung metastasis.

Development and validation of a nomogram for predicting overall survival of head and neck adenoid cystic carcinoma

This study aimed to develop and validate a nomogram using clinical variables to guide personalized treatment strategies for adenoid cystic carcinoma of the head and neck (ACCHN). Data from 1069 patients with ACCHN diagnosed between 2004 and 2015 in the Surveillance, Epidemiology, and End Results (SEER) database were used to construct the nomogram. External validation was performed using an independent cohort of 70 patients from Fujian Cancer Hospital. Multivariate Cox regression analysis was conducted using IBM SPSS version 26.0 and R Software version 4.2.3. The concordance index (C-index) and receiver operating characteristic (ROC) curves were used to assess the predictive accuracy of the nomogram. Age, tumor site, surgery, N stage, M stage, and TNM stage were identified as independent prognostic factors through univariate and multivariate Cox analyses. The nomogram demonstrated superior predictive performance compared to the TNM staging system, effectively stratifying patients into high-risk and low-risk groups. This nomogram offers a valuable tool for predicting overall survival in patients with ACCHN and tailoring individualized treatment approaches.

Epidemiological Study of Adenoid Cystic Carcinoma and Its Outcomes: Insights from the Surveillance, Epidemiology, and End Results (SEER) Database

OBJECTIVE

Adenoid cystic carcinoma (ACC) is a rare malignant tumor that mainly arises in the head and neck area. We aimed to compare the long-term survival of patients with ACC based on their geographic regions within the United States using the Surveillance, Epidemiology, and End Results (SEER) registry data.

METHODS

We queried the SEER database to evaluate the geographic distribution of ACC patients based on inpatient admissions. The states included in the study were divided into four geographical regions (Midwest, Northeast, South, and West) based on the U.S. Census Bureau-designated regions and divisions. Demographic and clinical variables were compared between the groups. Kaplan-Meier curves and Cox regression were used to assess late mortality.

RESULTS

A total of 5150 patients were included (4.2% from the Midwest, 17.2% from the Northeast, 22.5% from the South, and 56.1% from the West regions). The median follow-up was 12.3 (95% CI: 11.6-13.1 years). Median overall survival was 11.0 (95% CI: 9.2-NR years), 14.3 (95% CI: 12.4-16.4 years), 11.3 (95% CI: 9.7-14.8 years), and 12.0 (95% CI: 11.3-13.0 years) for Midwest, Northeast, South, and West regions, respectively. In multivariable analysis, older age, male sex, thoracic cancer, the presence of regional and distal disease, receiving chemotherapy, not undergoing surgical resection, and being treated in the West vs. Northeast region were found to be independent predictors of poor survival. We identified a significant survival difference between the different regions, with the West exhibiting the worst survival compared to the Northeast region.

CONCLUSIONS

In addition to the well-known predictors of late mortality in ACC (tumor location, stage, and treatment modalities), our study identified a lack of social support (being unmarried) and geographic location (West region) as independent predictors of late mortality in multivariable analysis. Further research is needed to explore the causal relationships.

Analysis of Response and Progression Patterns of Tyrosine Kinase Inhibitors in Recurrent or Metastatic Adenoid Cystic Carcinoma: A Post Hoc Analysis of Two KCSG Phase II Trials

PURPOSE

In this study, we evaluated 66 patients diagnosed with adenoid cystic carcinoma (ACC) enrolled in two Korean Cancer Study Group trials to investigate the response and progression patterns in recurrent and/or metastatic ACC treated with vascular endothelial growth factor receptor tyrosine kinase inhibitors (VEGFR-TKIs).

MATERIALS AND METHODS

We evaluated 66 patients diagnosed with ACC who were enrolled in the Korean Cancer Study Group trials. The tumor measurements, clinical data, treatment outcomes, and progression patterns of therapy were analyzed.

RESULTS

In the 66 patients (53 receiving axitinib and 13 receiving nintedanib), the disease control rate was 61%, and three patients achieved partial response. The median follow-up, median progression-free survival (PFS), overall survival, and 6-month PFS rate were 27.6%, 12.4%, and 18.1% months and 62.1%, respectively. Among 42 patients who experienced progression, 27 (64.3%) showed target lesion progression. Bone metastasis was an independent poor prognostic factor.

CONCLUSION

Overall, most patients demonstrated stable disease with prolonged PFS; however, prominent target lesion progression occurred in some patients. Thus, PFS may capture VEGFR-TKI efficacy better than the objective response rate.

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.

Systemic therapy in the management of metastatic or locally recurrent adenoid cystic carcinoma of the salivary glands: a systematic review of the last decade

IMPORTANCE

Recurrent/metastatic adenoid cystic carcinoma (R/M AdCC) presents a clinical challenge with limited treatment options, particularly in the face of unsatisfactory efficacy from current therapeutic approaches. This review underscores the unmet clinical needs in managing R/M AdCC, emphasising the imperative for novel therapeutic strategies to address this critical gap.

OBJECTIVE

The primary objective of this review is to comprehensively analyse and assess trials investigating therapeutic approaches for R/M AdCC. Emphasis is placed on endpoints such as tumour response rates and progression-free survival. The specific interventions, populations, and outcomes examined in these trials will be detailed to provide a focused and informative systematic review.

EVIDENCE REVIEW

The systematic search spanned databases, including PubMed, EMBASE, and the Cochrane database of systematic reviews. Employing terms like "Carcinoma, Adenoid Cystic" and "trial," the search focused on English full-text articles from April 1, 2010, to August 9, 2023. Inclusion criteria encompassed studies with patients having R/M AdCC, involving drug interventions. Study quality was assessed using the Newcastle-Ottawa Scale for retrospective studies, Cochrane ROBINS-I tool for non-randomised trials, and the ROB-2 tool for randomised controlled trials.

FINDINGS

A total of 46 trials involving 1244 patients are included in this review, encompassing a variety of therapeutic approaches for R/M AdCC. Targeted therapies, particularly Apatinib at 500 mg, exhibit efficacy with a 47.1% objective response rate (ORR). Conversely, immunotherapeutic agents demonstrate suboptimal performance, with an overall ORR ranging from 0 to 18%. While Apatinib shows promise, the review underscores the imperative for a thorough exploration of drugs targeting unique mechanisms in the immunologically cold nature of R/M AdCC.

CONCLUSIONS AND RELEVANCE

Substantial progress in systemic therapy for R/M AdCC is evident, driven by early-phase clinical trials, particularly with promising outcomes in VEGF-2 inhibitors. However, challenges persist, notably in immunotherapy due to the cancer's immunologically cold nature. Ongoing research, prioritising early-stage trials, is crucial, emphasising exploration of emerging therapies like cell therapy and antibody-drug conjugates. Transitioning to Phase III trials is essential for more precise therapeutic insights. Collaborative efforts and a focus on personalised precision medicine are vital for overcoming challenges and advancing our understanding of treatment efficacy in this rare cancer.

Personalized Immunotherapy Achieves Complete Response in Metastatic Adenoid Cystic Carcinoma Despite Lack of Conventional Biomarkers

There is currently no effective treatment strategy for recurrent/metastatic adenoid cystic carcinoma (R/M ACC). Furthermore, recent single-agent and combination immunotherapy trials have failed in unselected ACC cohorts, unlike non-ACC salivary gland cancers. Genomic profiling revealed no actionable targets but NOTCH1 and KDM6A frameshift and CTCF splice site mutations (no MYB/L fusion) with a low tumor mutational burden (TMB), microsatellite stable (MSS) and negative programmed death ligand 1 (PD-L1) were observed. We recommended an anti-programmed cell death protein 1 (anti-PD-1) plus anti-Cytotoxic T-lymphocyte-associated protein 4 (anti-CTLA-4) combination based on TMB 2-fold greater-than-median TMB in ACC, tumor harboring multiple immunogenic frameshift or splice site mutations, and PD-L1 negativity. Accordingly, we achieved a complete response in a radiotherapy (RT) and chemotherapy (CT)-refractory patient with locally recurrent lacrimal gland (LG) ACC and lung metastasis following personalized immunotherapy in combination with integrative therapeutics. Therefore, it is crucial to assess not only conventional immune biomarkers but also patient-specific parameters, especially in "immune-cold" cancer types.

Tracheal Tumors: Clinical Practice Guidelines for Palliative Treatment and Follow-Up

A substantial portion of patients with advanced cancer cannot be cured, regardless of the therapeutic methods employed. Hence, rational palliative causal treatment becomes crucial. Representative studies specifically addressing the exclusive palliative treatment of patients diagnosed with tracheal cancers have not been identified. In most studies, patients treated palliatively constituted a subset of the overall evaluated group. A thorough literature review was conducted, focusing on three types of palliative treatment: palliative radiotherapy, palliative surgical procedures, and systemic treatment for advanced disease. This review uniquely fills a significant gap in the existing literature by providing the first comprehensive and updated clinical practice guidelines specifically focused on the palliative treatment of tracheal tumors. The proposed guidelines emphasize the unique clinical challenges and treatment strategies pertinent to palliative care in tracheal tumors, which are not adequately covered in existing guidelines for other thoracic malignancies.

Prognostic Impact of Notch1 Intracellular Domain, P63, and c-MYC in Lacrimal Gland Adenoid Cystic Carcinoma

Purpose

We assessed whether NICD1 expression, c-MYC expression, and P63 expression by immunohistochemistry (IHC) correlate with prognosis and high-risk clinicopathological features in lacrimal gland adenoid cystic carcinoma (ACC).

Methods

Records of patients with lacrimal gland ACC who underwent surgery between 1998 to 2018 were reviewed. Clinicopathologic and treatment data were collected. Tumor tissues were subjected to light microscopy and IHC.

Results

Of 43 patients treated during the study period, 21 had archived tumor tissue available and were included. The median age at diagnosis was 47 years, and 13 patients (62%) were male. Thirteen patients (62%) had T2 disease, and none had nodal or distant metastasis at diagnosis. Tumors were positive for NICD1 expression in eight cases (38%), c-MYC expression in eight (38%), and P63 expression in 11 (52%). Positive NICD1 expression was associated with predominantly solid (vs. cribriform/tubular) pattern (P < 0.001), treatment with orbital exenteration (vs. eye-sparing surgery) (P = 0.008), local recurrence (P = 0.047), and death (P = 0.012). Negative P63 expression was associated with predominantly solid pattern (P = 0.001), local recurrence (P = 0.012), distant metastasis (P = 0.001), and death (P = 0.035). A higher percentage of tumor cells staining for c-MYC was associated with presence of perineural invasion (P = 0.036). Positive NICD1 expression was associated with worse disease-free survival (hazard ratio, 6.27; 95% CI, 1.29-30.46), whereas positive P63 expression was associated with better disease-free survival (hazard ratio, 0.03; 95% CI, 0.0002-0.26).

Conclusions

IHC for NICD1 and P63 should be considered in lacrimal gland ACC because of their prognostic value and potential as treatment targets.

Surgical management of patients with distant metastasized adenoid cystic carcinoma of the head and neck

BACKGROUND

Adenoid cystic carcinoma (ACC) is a rare and malignant tumor of the salivary glands. Despite its slow-growing nature, this clinical entity is notorious for presenting with distant metastasis (DM) which significantly worsens patient outcomes. The role of surgery in patients with ACC and distant metastasis (DM) remains controversial.

METHODS

We conducted a retrospective analysis of 47 patients with ACC who underwent surgery for the primary tumor and presented with DM at baseline or developed DM during follow-up. We compared survival outcomes between patients with DM at baseline (Group A) and those who developed DM during follow-up (Group B).

RESULTS

The median overall survival (OS) for the entire cohort was 88%. Patients with DM at baseline (Group A) had significantly worse OS (51%) compared to those without DM at baseline (Group B) (91%; P = .04). Local recurrence (LR) was associated with poor survival in both groups. However, salvage surgery for LR+DM was associated with improved OS compared to palliative treatment (100% vs 77%; P = .79).

CONCLUSION

Our findings suggest that surgery for the primary tumor of ACC may provide survival benefits in patients with DM. Salvage surgery should be considered particularly for patients who develop local recurrence and distant metastasis during follow-up.

Systemic therapies for salivary gland carcinoma (excluding adenoid cystic carcinoma): REFCOR recommendations by the formal consensus method

OBJECTIVE

To determine the therapeutic indications for systemic medical treatment in the management of salivary gland carcinoma (excluding adenoid cystic carcinoma) according to the clinical situation.

MATERIALS AND METHODS

The French Network of Rare Head and Neck Tumors (REFCOR) formed a steering group who drafted a narrative review of the literature published on Medline and proposed recommendations. The level of adherence to the recommendations was then assessed by a rating group, according to the formal consensus method.

RESULTS

Salivary gland carcinoma is rare and there is currently insufficient evidence to indicate chemotherapy at the localized stage. At the metastatic stage, initial management can be based on a phase of monitoring for indolent disease. Some histological subtypes (salivary duct carcinoma and adenocarcinoma) are more aggressive and require systemic treatment from the outset. To guide systemic treatment, it is recommended to perform immunohistochemistry and molecular biology analyses (overexpression of HER2 and androgen receptors, NTRK fusion, next-generation sequencing).

CONCLUSION

Salivary gland carcinoma is a rare tumor for which there are currently few effective medical treatments. It is therefore recommended to include patients in clinical trials.

Systemic therapies for salivary gland cancer: Adenoid cystic carcinoma. REFCOR recommendations by the formal consensus method

OBJECTIVE

To determine the therapeutic indications for systemic medical treatment in the management of adenoid cystic carcinoma (ACC) according to the clinical situation.

MATERIALS AND METHODS

The French Network of Rare Head and Neck Tumors (REFCOR) formed a steering group, which drafted a narrative review of the literature published on Medline and proposed recommendations. The level of adherence to the recommendations was then assessed by a rating group, according to the formal consensus method.

RESULTS

ACCs are rare tumors and there is currently insufficient evidence to indicate chemotherapy at the localized stage. At the metastatic stage, progression is often slow. In case of oligometastatic ACC, local treatment should be discussed. The most often indolent nature of polymetastatic ACC can allow management by active surveillance. Molecular screening is recommended, for abnormalities potentially accessible to targeted therapy.

CONCLUSION

ACCs are rare tumors for which there are currently few effective medical treatments. It is therefore recommended to include patients in clinical trials.

Extracellular Vesicles Containing circMYBL1 Induce CD44 in Adenoid Cystic Carcinoma Cells and Pulmonary Endothelial Cells to Promote Lung Metastasis

Adenoid cystic carcinoma (ACC) is a rare malignant epithelial neoplasm that arises in secretory glands and commonly metastasizes to the lungs. MYBL1 is frequently overexpressed in ACC and has been suggested to be a driver of the disease. In this study, we identified a circular RNA (circRNA) derived from MYBL1 pre-mRNA that was accompanied by the overexpression of MYBL1 in ACC. Overexpression of circMYBL1 was correlated with increased lung metastasis and poor overall survival in patients with ACC. Ectopic circMYBL1 overexpression promoted malignant phenotypes and lung metastasis of ACC cells. Mechanistically, circMYBL1 formed a circRNA-protein complex with CCAAT enhancer-binding protein β (CEBPB), which inhibited ubiquitin-mediated degradation and promoted nuclear translocation of CEBPB. In the nucleus, circMYBL1 increased the binding of CEBPB to the CD44 promoter region and enhanced its transcription. In addition, circMYBL1 was enriched in small extracellular vesicles (sEV) isolated from the plasma of patients with ACC. Treatment with sEVs containing circMYBL1 in sEVs enhanced prometastatic phenotypes of ACC cells, elevated the expression of CD44 in human pulmonary microvascular endothelial cells (HPMEC), and enhanced the adhesion between HPMECs and ACC cells. Moreover, circMYBL1 encapsulated in sEVs increased the arrest of circulating ACC cells in the lung and enhanced lung metastatic burden. These data suggest that circMYBL1 is a tumor-promoting circRNA that could serve as a potential biomarker and therapeutic target for ACC. Significance: circMYBL1 stabilizes CEBPB and upregulates CD44 to promote adhesion between cancer cells and endothelial cells and enables lung metastasis of adenoid cystic carcinoma, suggesting that inhibition of this axis could improve patient outcomes.

The Potential Role of PSMA-Targeted PET in Salivary Gland Malignancies: An Updated Systematic Review

BACKGROUND

Recent studies have suggested using positron emission tomography/computed tomography (PET/CT) with prostate-specific membrane antigen (PSMA)-targeting radiopharmaceuticals for the detection of salivary gland malignancies (SGM), particularly adenoid-cystic carcinoma (ACC).

METHODS

The authors conducted an extensive review of the scientific literature to examine the potential diagnostic role of PET/CT using PSMA-targeting radiopharmaceuticals in salivary gland malignancies (SGMs) and adenoid cystic carcinoma (ACC). This study included newly diagnosed SGM patients and those with disease recurrence in their imaging evaluation.

RESULTS

This updated systematic review included a total of six studies that examined the diagnostic performance of PSMA-targeted PET/CT in ACC. The articles provided evidence of a high detection rate of PSMA-targeting PET/CT in ACC across all clinical contexts examined. SGMs other than ACC exhibited poorer diagnostic performance.

CONCLUSIONS

PSMA-targeted PET/CT seems promising in detecting ACC lesions; moreover, PSMA appears to be a suitable potential target for radioligand therapy. Prospective multicentric studies are warranted to strengthen the role of PSMA-targeting radiopharmaceuticals in ACC, as both diagnostic and theragnostic agents.

Molecular characterization of the salivary adenoid cystic carcinoma immune landscape by anatomic subsites

Adenoid cystic carcinoma (AdCC) is a slow-growing salivary gland malignancy that relapses frequently. AdCCs of the submandibular gland exhibit unique differences in prognosis and treatment response to adjuvant radiotherapy compared to other sites, yet the role of tumor anatomic subsite on gene expression and tumor immune microenvironment (TIME) composition remains unclear. We used 87 samples, including 48 samples (27 AdCC and 21 normal salivary gland tissue samples) from 4 publicly available AdCC RNA sequencing datasets, a validation set of 33 minor gland AdCCs, and 39 samples from an in-house cohort (30 AdCC and 9 normal salivary gland samples). RNA sequencing data were used for single sample gene set enrichment analysis and TIME deconvolution. Quantitative PCR and multiplex immunofluorescence were performed on the in-house cohort. Wilcoxon rank-sum, nonparametric equality-of-medians tests and linear regression models were used to evaluate tumor subsite differences. AdCCs of different anatomic subsites including parotid, submandibular, sublingual, and minor salivary glands differed with respect to expression of several key tumorigenic pathways. Among the three major salivary glands, the reactive oxygen species (ROS)/nuclear factor erythroid 2-related factor 2 (NRF2) pathway signature was significantly underexpressed in AdCC of submandibular compared to parotid and sublingual glands while this association was not observed among normal glands. Additionally, the NRF2 pathway, whose expression was associated with favorable overall survival, was overexpressed in AdCCs of parotid gland compared to minor and submandibular glands. The TIME deconvolution identified differences in CD4+ T cell populations between AdCC of major and minor glands and natural killer (NK) cells among AdCC of minor, submandibular, and parotid glands while plasma cells were enriched in normal submandibular glands compared to other normal gland controls. Our data reveal key molecular differences in AdCC of different anatomic subsites. The ROS and NRF2 pathways are underexpressed in submandibular and minor AdCCs compared to parotid gland AdCCs, and NRF2 pathway expression is associated with favorable overall survival. The CD4+ T, NK, and plasma cell populations also vary by tumor subsites, suggesting that the observed submandibular AdCC tumor-intrinsic pathway differences may be responsible for influencing the TIME composition and survival differences.

A Retrospective Analysis of Salivary Gland Tumor Cases: Histological Variations and Clinical Outcomes

Background

Salivary gland tumors (SGTs) present a diagnostic challenge due to their diverse histological subtypes and variable clinical behavior.

Methods

This research conducted a retrospective analysis of SGT cases diagnosed and managed at a tertiary care center between 2017 and 2022. Clinical and pathological data were retrieved from medical records and histopathology reports. Statistical analysis was performed to identify factors associated with recurrence and survival outcomes.

Results

A total of 150 SGT cases were included, comprising 70% benign and 30% malignant tumors. Pleomorphic adenoma and adenoid cystic carcinoma were the most prevalent benign and malignant subtypes, respectively. Surgical resection was the primary treatment modality, with varying recurrence rates observed among different treatment groups.

Conclusion

The current study provides insights into the histological variations and clinical outcomes of SGTs. Surgical resection remains the mainstay of treatment, with adjuvant therapy reserved for cases with adverse prognostic factors. Further research is needed to optimize therapeutic strategies and improve patient outcomes.

Vascular Endothelial Growth Factor Receptor Inhibitors for Recurrent or Metastatic Adenoid Cystic Carcinoma: A Systematic Review and Meta-Analysis

Importance

There is no systemic therapy for recurrent or metastatic adenoid cystic carcinoma (ACC) approved by the US Food and Drug Administration.

Objective

To examine the efficacy, safety, and tolerability of vascular endothelial growth factor receptor (VEGFR) inhibitors in recurrent or metastatic ACC.

Data Sources

PubMed, Embase, and Cochrane Library were systematically searched for studies of VEGFR inhibitors in recurrent or metastatic ACC from database inception to August 31, 2023.

Study Selection

Inclusion criteria were prospective clinical trials of recurrent or metastatic ACC treated with VEGFR inhibitors, reporting at least 1 outcome of interest specifically for ACC. Of 1963 identified studies, 17 (0.9%) met inclusion criteria.

Data Extraction and Synthesis

The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) reporting guideline was followed to extract data. Data were pooled using a random-effects generalized linear mixed model with 95% CIs.

Main Outcomes and Measures

The primary efficacy outcome was best overall response to VEGFR inhibitors, including objective response, stable disease, or progressive disease (PD). Safety and tolerability outcomes included incidence of grade 3 or higher adverse events, rates of exit from trial due to PD or drug-related toxic effects, and dose reduction rate (DRR).

Results

A total of 17 studies comprising 560 patients with recurrent or metastatic ACC treated with 10 VEGFR inhibitors were included. The objective response rate was 6% (95% CI, 3%-12%; I2 = 71%) and stable disease was the most frequent best overall response (82%; 95% CI, 74%-87%; I2 = 67%). The 6-month disease control (defined as objective response and stable disease) rate was 54% (95% CI, 45%-62%; I2 = 52%). The rate of grade 3 or higher adverse events was 53% (95% CI, 42%-64%; I2 = 81%) and of DRR was 59% (95% CI, 40%-76%). Most patients (57%; 95% CI, 44%-70%; I2 = 83%) continued therapy until PD; 21% (95% CI, 15%-28%; I2 = 62%) of patients suspended therapy for toxic effects. In subgroup analysis by specific VEGFR inhibitor, the objective response rate was 14% (95% CI, 7%-25%; I2 = 0%), stable disease rate was 76% (95% CI, 63%-85%; I2 = 0%), proportion treated until PD was 61% (95% CI, 14%-94%; I2 = 94%), and DRR was 78% (95% CI, 66%-87%; I2 = 39%) with lenvatinib. Corresponding axitinib results were objective response rate of 8% (95% CI, 4%-15%; I2 = 0%) and stable disease rate of 85% (95% CI, 72%-92%; I2 = 69%), with 73% (95% CI, 63%-82%; I2 = 0%) of patients treated until PD, and the DRR was 22% (95% CI, 12%-38%; I2 = 77%). Rivoceranib had the highest objective response rate (24%; 95% CI, 7%-57%) but high heterogeneity among studies (I2 = 95%) and the lowest rate of patients who continued therapy until PD (35%; 95% CI, 20%-55%; I2 = 90%).

Conclusions and Relevance

This systematic review and meta-analysis found that VEGFR inhibitors were associated with high rates of disease stabilization in recurrent or metastatic ACC. Of 10 included VEGFR inhibitors, lenvatinib and axitinib were associated with the best combined and consistent efficacy, safety, and tolerability profiles, substantiating their inclusion in treatment guidelines.

Exploiting BRAF mutations in the therapeutic approach towards oral and maxillofacial tumors

Oral and maxillofacial tumors pose a significant clinical challenge due to their tendency to recur, despite advancements in surgical removal techniques. The jaw's intricate structure further complicates treatments and affects patient quality of life. Consequently, emphasis has shifted towards pharmacological interventions, to potentially reduce invasive surgical procedures. One promising approach targets BRAF mutations, specifically the common V600E mutation. BRAF, a critical protein kinase, regulates cell growth and differentiation via the RAS-RAF-MEK-ERK-MAP kinase pathway. A specific nucleotide change at position 1799, swapping Thymine (T) for Adenine (A), results in the V600E mutation, causing unchecked cell growth. This mutation is common in certain oral and maxillofacial tumors like ameloblastoma. A recent neoadjuvant therapy targeting BRAF, involving the use of dabrafenib and trametinib, has showcased a promising, safe, and effective strategy for organ preservation in the treatment of mandibular ameloblastoma. This convergence of molecular insights and targeted therapies holds the key to managing BRAF-mutated oral and maxillofacial tumors effectively, promising improved patient outcomes.

Advances in Radioligand Theranostics in Oncology

Theranostics with radioligands (radiotheranostics) has played a pivotal role in oncology. Radiotheranostics explores the molecular targets expressed on tumor cells to target them for imaging and therapy. In this way, radiotheranostics entails non-invasive demonstration of the in vivo expression of a molecular target of interest through imaging followed by the administration of therapeutic radioligand targeting the tumor-expressed molecular target. Therefore, radiotheranostics ensures that only patients with a high likelihood of response are treated with a particular radiotheranostic agent, ensuring the delivery of personalized care to cancer patients. Within the last decades, a couple of radiotheranostics agents, including Lutetium-177 DOTATATE (177Lu-DOTATATE) and Lutetium-177 prostate-specific membrane antigen (177Lu-PSMA), were shown to prolong the survival of cancer patients compared to the current standard of care leading to the regulatory approval of these agents for routine use in oncology care. This recent string of successful approvals has broadened the interest in the development of different radiotheranostic agents and their investigation for clinical translation. In this work, we present an updated appraisal of the literature, reviewing the recent advances in the use of established radiotheranostic agents such as radioiodine for differentiated thyroid carcinoma and Iodine-131-labeled meta-iodobenzylguanidine therapy of tumors of the sympathoadrenal axis as well as the recently approved 177Lu-DOTATATE and 177Lu-PSMA for differentiated neuroendocrine tumors and advanced prostate cancer, respectively. We also discuss the radiotheranostic agents that have been comprehensively characterized in preclinical studies and have shown some clinical evidence supporting their safety and efficacy, especially those targeting fibroblast activation protein (FAP) and chemokine receptor 4 (CXCR4) and those still being investigated in preclinical studies such as those targeting poly (ADP-ribose) polymerase (PARP) and epidermal growth factor receptor 2.

Efficacy of acupoint injection of metoclopramide for post-chemotherapy vomiting: A systematic review and meta-analysis

BACKGROUND

Vomiting is one of the most common adverse events of chemotherapy. The purpose of this study was to systematically review the clinical efficacy of acupoint injection of metoclopramide in the treatment of post-chemotherapy vomiting.

METHODS

We searched 4 general English databases and 4 conventional Chinese databases, all with a time frame from database creation to December 2022. The retrieved clinical trials of acupoint injection of metoclopramide for post-chemotherapy vomiting were then subjected to meta-analysis and trial sequential analysis.

RESULTS

A total of 12 studies were included, with a total sample size of 965 cases. Meta-analysis showed that acupoint injection of metoclopramide was effective in improving anti-vomiting effective rate [odds ratio = 5.67, 95% confidence interval = (3.80,8.47), P < .00001] compared with intramuscular/intravenous injection, and trial sequential analysis showed that this benefit was conclusive. Subgroup analysis demonstrated that acupoint injection significantly improved the anti-vomiting effective rate at doses of 10 mg qd, 20 mg qd, and 30 mg qd, as well as at durations of 1 day and 5 days. Subgroup analysis also indicated that injection at the Zusanli acupoint significantly increased the anti-vomiting effective rate, while injection at the Neiguan acupoint had an anti-vomiting effective rate comparable to that of the control group. Harbord regression showed no significant publication bias (P = .730).

CONCLUSION

Acupoint injection of metoclopramide for post-chemotherapy vomiting is more effective than intramuscular and intravenous injections and is not limited by dose or duration of treatment, which may be the preferred way of administration.

MYB alternative promoter activity is increased in adenoid cystic carcinoma metastases and is associated with a specific gene expression signature

OBJECTIVE

Adenoid cystic carcinoma (ACC) is a head and neck cancer with a poor long-term prognosis that shows frequent local recurrences and distant metastases. The tumors are characterized by MYB oncogene activation and are notoriously unresponsive to systemic therapies. The biological underpinnings behind therapy resistance of disseminated ACC are largely unknown. Here, we have studied the molecular and clinical significance of MYB alternative promoter (TSS2) usage in ACC metastases.

MATERIALS AND METHODS

MYB TSS2 activity was investigated in primary tumors and metastases from 26 ACC patients using RNA-sequencing and quantitative real-time PCR analysis. Differences in global gene expression between MYB TSS2 high and low cases were studied, and pathway analyses were performed.

RESULTS

MYB TSS2 activity was significantly higher in ACC metastases than in primary tumors (median activity 15.1 vs 3.0, P = 0.0003). MYB TSS2 high ACC metastases showed a specific gene expression signature, including increased expression of multi-drug resistance genes and canonical MYB target genes, and suppression of the p53 and NOTCH pathways.

CONCLUSIONS

Collectively, our findings indicate that elevated MYB TSS2 activity is associated with metastases, potential drug resistance, and augmented MYB-driven gene expression in ACC. Our study advocates the need for new therapies that specifically target MYB and drug resistance mechanisms in disseminated ACC.

Clinical study of salivary gland malignant tumor with skull base metastasis

PURPOSE

To investigate the clinical performance, pathological characteristics, treatment and prognosis of salivary gland malignant tumor (SGMT) with skull base metastasis.

METHODS

Five SGMT patients with skull base metastasis were retrospectively studied. Major clinical symptoms included headache, facial paralysis, and ear hearing loss. Three patients had previous history of SGMT resection. All patients underwent preoperative computed tomography (CT) and magnetic resonance imaging (MRI). Craniotomy was performed in three patients, and all the five patients underwent radiotherapy and chemotherapy.

RESULTS

Two patients were confirmed as having adenocarcinoma, one patient was pathologically confirmed to have squamous cell carcinoma, one patient had ductal carcinoma, and one patient had acinar cell carcinoma. One patient died after 2 years of treatment, and the remaining 4 patients were followed up for 6 ∼ 24 months, suggesting that the tumor size was not enlarged or showed no local recurrence.

CONCLUSION

SGMT with skull base metastasis is extremely rare, and due to similar imaging characteristics, it can be easily misdiagnosed as meningioma or schwannoma. Early diagnosis, extent of invasion, surgery and combination of chemotherapy and radiotherapy are the prognostic factors of the disease.

First Use of AXL Targeting in Metastatic, Refractory, Adenoid Cystic Carcinoma: A Case Report

First use of AXL-targeting in adenoid cystic carcinoma (ACC); with positive results, ACC now included in AXL studies.

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.

B-cell specific Moloney murine leukemia virus insertion site 1 contributes to invasion, metastasis, and poor prognosis in salivary adenoid cystic carcinoma

Background/purpose

Upregulation of B-cell specific Moloney murine leukemia virus insertion site 1 (BMI-1) has been involved in the invasion, metastasis, and poor prognosis of many cancers. The aim of this study was to evaluate the levels and clinical significance of BMI-1 in saliva of patients with salivary adenoid cystic carcinoma (SACC), and to analyze biological function and mechanism of BMI-1 in the invasion and metastasis of SACC.

Materials and methods

The levels of BMI-1 in saliva and tumor tissues of SACC patients were determined. The correlation of salivary BMI-1 levels with clinicopathological parameters and clinical outcomes in patients with SACC was analyzed. Additionally, the effects of BMI-1 on wound-healing, transwell invasion, and epithelial-mesenchymal transition (EMT)-related protein expression in vitro as well as on tumorigenicity and experimental lung metastasis in vivo were investigated through exogenous overexpression and silencing of BMI-1 in SACC cells.

Results

BMI-1 levels increased in saliva and tumor tissues in SACC patients with invasion or metastasis. High salivary BMI-1 levels were correlated with poor TNM stage, poor overall survival, and disease-free survival. Exogenous expression of BMI-1 in SACC-83 promoted its migration and invasion, while silencing BMI-1 in SACC-LM inhibited its migration and invasion in vitro and suppressed tumorigenesis and lung metastasis in vivo. Furthermore, BMI-1 regulated the expression of EMT-related proteins in SACC.

Conclusion

Our study shows that BMI-1 can serve as a valuable biomarker to identify tumor invasion and metastasis in SACC, predict its prognosis, and act as a promising therapeutic target for SACC.

Analysis of B7-H4 Expression Across Salivary Gland Carcinomas Reveals Adenoid Cystic Carcinoma-Specific Prognostic Relevance

B7-H4 (VTCN1), a member of the B7 family, is overexpressed in several types of cancer. Here we investigated the pattern of expression of B7-H4 in salivary gland carcinomas (SGC) and assessed its potential as a prognostic marker and therapeutic target. Immunohistochemistry (IHC) analyses were performed in a cohort of 340 patient tumors, composed of 124 adenoid cystic carcinomas (ACC), 107 salivary duct carcinomas (SDC), 64 acinic cell carcinomas, 36 mucoepidermoid carcinomas (MEC), 9 secretory carcinomas (SC), as well as 20 normal salivary glands (controls). B7-H4 expression was scored and categorized into negative (<5% expression of any intensity), low (5%-70% expression of any intensity or >70% with weak intensity), or high (>70% moderate or strong diffuse intensity). The associations between B7-H4 expression and clinicopathologic characteristics, as well as overall survival, were assessed. Among all tumors, B7-H4 expression was more prevalent in ACC (94%) compared with those of SC (67%), MEC (44%), SDC (32%), and acinic cell carcinomas (0%). Normal salivary gland tissue did not express B7-H4. High expression of B7-H4 was found exclusively in ACC (27%), SDC (11%), and MEC (8%). In SDC, B7-H4 expression was associated with female gender (P = .002) and lack of androgen receptor expression (P = .012). In ACC, B7-H4 expression was significantly associated with solid histology (P < .0001) and minor salivary gland primary (P = .02). High B7-H4 expression was associated with a poorer prognosis in ACC, regardless of clinical stage and histologic subtype. B7-H4 expression was not prognostic in the non-ACC SGC evaluated. Our comparative study revealed distinct patterns of B7-H4 expression according to SGC histology, which has potential therapeutic implications. B7-H4 expression was particularly high in solid ACC and was an independent prognostic marker in this disease but not in the other SGC assessed.

Nivolumab plus ipilimumab in advanced salivary gland cancer: a phase 2 trial

Salivary gland cancers (SGCs) are rare, aggressive cancers without effective treatments when metastasized. We conducted a phase 2 trial evaluating nivolumab (nivo, anti-PD-1) and ipilimumab (ipi, anti-CTLA-4) in 64 patients with metastatic SGC enrolled in two histology-based cohorts (32 patients each): adenoid cystic carcinoma (ACC; cohort 1) and other SGCs (cohort 2). The primary efficacy endpoint (≥4 objective responses) was met in cohort 2 (5/32, 16%) but not in cohort 1 (2/32, 6%). Treatment safety/tolerability and progression-free survival (PFS) were secondary endpoints. Treatment-related adverse events grade ≥3 occurred in 24 of 64 (38%) patients across both cohorts, and median PFS was 4.4 months (95% confidence interval (CI): 2.4, 8.3) and 2.2 months (95% CI: 1.8, 5.3) for cohorts 1 and 2, respectively. We present whole-exome, RNA and T cell receptor (TCR) sequencing data from pre-treatment and on-treatment tumors and immune cell flow cytometry and TCR sequencing from peripheral blood at serial timepoints. Responding tumors universally demonstrated clonal expansion of pre-existing T cells and mutational contraction. Responding ACCs harbored neoantigens, including fusion-derived neoepitopes, that induced T cell responses ex vivo. This study shows that nivo+ipi has limited efficacy in ACC, albeit with infrequent, exceptional responses, and that it could be promising for non-ACC SGCs, particularly salivary duct carcinomas. ClinicalTrials.gov identifier: NCT03172624 .

A Phase II Trial of Rivoceranib, an Oral Vascular Endothelial Growth Factor Receptor 2 Inhibitor, for Recurrent or Metastatic Adenoid Cystic Carcinoma

PURPOSE

This open-label, single-arm, phase II study evaluated the vascular endothelial growth factor receptor 2 (VEGFR2) tyrosine kinase inhibitor (TKI) rivoceranib in patients with recurrent or metastatic (R/M) adenoid cystic carcinoma (ACC).

PATIENTS AND METHODS

Eligible patients had confirmed disease progression per Response Evaluation Criteria in Solid Tumors (RECIST) with ≥20% increase in radiologically or clinically measurable lesions or appearance of new lesions within the preceding 6 months. Patients received oral rivoceranib 700 mg once daily. Primary outcomes were objective response rate (ORR) by investigator review and by blinded independent review committee (BIRC).

RESULTS

Eighty patients were enrolled and 72 were efficacy evaluable. Seventy-four patients had distant metastases and 49 received prior systemic treatment (14 received VEGFR TKIs). Per investigator and BIRC, respectively, ORR was 15.3% [95% confidence interval (95% CI), 7.9-25.7] and 9.7% (95% CI, 4.0-19.0); median duration of response was 14.9 months (95% CI, 4.9-17.3) and 7.2 months (95% CI, 3.5-8.4); and median progression-free survival was 9.0 months (95% CI, 7.3-11.5) and 9.0 months (95% CI, 7.7-11.5). Grade ≥3 treatment-related adverse events occurred in 56 patients (70.0%); the most common were hypertension (34, 42.5%) and stomatitis (6, 7.5%). Four grade 5 events occurred with one attributed to rivoceranib (epistaxis). Sixty-eight patients (85.0%) had ≥1 dose modifications and 16 patients (20.0%) discontinued rivoceranib for toxicity.

CONCLUSIONS

In patients with progressing R/M ACC, rivoceranib demonstrated antitumor activity and a manageable safety profile consistent with other VEGFR TKIs.

Comprehensive molecular characterization of adenoid cystic carcinoma reveals tumor suppressors as novel drivers and prognostic biomarkers

Adenoid cystic carcinoma (ACC) is a MYB-driven head and neck malignancy with high rates of local recurrence and distant metastasis and poor long-term survival. New effective targeted therapies and clinically useful biomarkers for patient stratification are needed to improve ACC patient survival. Here, we present an integrated copy number and transcriptomic analysis of ACC to identify novel driver genes and prognostic biomarkers. A total of 598 ACCs were studied. Clinical follow-up was available from 366 patients, the largest cohort analyzed to date. Copy number losses of 1p36 (70/492; 14%) and of the tumor suppressor gene PARK2 (6q26) (85/343; 25%) were prognostic biomarkers; patients with concurrent losses (n = 20) had significantly shorter overall survival (OS) than those with one or no deletions (p < 0.0001). Deletion of 1p36 independently predicted short OS in multivariate analysis (p = 0.02). Two pro-apoptotic genes, TP73 and KIF1B, were identified as putative 1p36 tumor suppressor genes whose reduced expression was associated with poor survival and increased resistance to apoptosis. PARK2 expression was markedly reduced in tumors with 6q deletions, and PARK2 knockdown increased spherogenesis and decreased apoptosis, indicating that PARK2 is a tumor suppressor in ACC. Moreover, analysis of the global gene expression pattern in 30 ACCs revealed a transcriptomic signature associated with short OS, multiple copy number alterations including 1p36 deletions, and reduced expression of TP73. Taken together, the results indicate that TP73 and PARK2 are novel putative tumor suppressor genes and potential prognostic biomarkers in ACC. Our studies provide new important insights into the pathogenesis of ACC. The results have important implications for biomarker-driven stratification of patients in clinical trials. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Induction of perineural invasion in salivary adenoid cystic carcinoma by circular RNA RNF111

OBJECTIVE

Local recurrence, distant metastasis, and perineural invasion (PNI) viciously occur in salivary adenoid cystic carcinoma (SACC), resulting in a poor prognosis. This study aimed to explore the mechanism by which circular RNA RNF111 (circ-RNF111) regulates PNI in SACC by targeting the miR-361-5p/high mobility group box 2 (HMGB2) axis.

METHOD

Circ-RNF111 and HMGB2 were highly expressed in SACC specimens, while miR-361-5p was underexpressed. Functional experiments showed that ablating circ-RNF111 or promoting miR-361-5p hindered the biological functions and PNI of SACC-LM cells.

RESULTS

HMGB2 overexpression induced the reversal of SACC-LM cell biological functions and PNI caused by circ-RNF111 knockout. Furthermore, reduction of circ-RNF111 suppressed PNI in a SACC xenograft model. Circ-RNF111 regulated HMGB2 expression through targeted modulation of miR-361-5p.

CONCLUSION

Taken together, circ-RNF111 stimulates PNI in SACC by miR-361-5p/HMGB2 axis and may serve as a potential therapeutic target for SACC.

NISCAHN: a phase II trial of nivolumab in patients with salivary gland carcinoma (Unicancer ORL-08)

Objective

Salivary gland cancers (SGC) are rare cancers with currently no standard treatment for recurrent/metastatic disease. Based on checkpoint inhibitors benefit in a broad range of tumours, NIvolumab in Salivary gland CArcinoma of the Head and Neck (NISCAHN) evaluated nivolumab efficacy in SGC.

Methods and analysis

In this phase II single-stage Fleming design, patients with SGC with a progressive disease progression within 6 months prior to entering the study, were divided into ACC (adenoid cytic carcinoma) and non-ACC. All received nivolumab for a maximum of 12 months. The primary endpoint was the non-progression rate at 6 months (NPR6m) according to Response Evaluation Criteria in Solid Tumors V.1.1. Secondary endpoints included progression-free survival (PFS), overall survival (OS), overall response rate (ORR), tumour growth rate, safety and quality of life (health-related quality of life).

Results

46 patients with ACC and 52 patients without ACC were enrolled over 1 year. Median follow-up was respectively 29.2 months and 16.9 months for patients with ACC and non-ACC. In the ACC cohort, with 15/45 patients non-progressive at 6 months, the primary endpoint was met (33.3%; 95% CI 21.8 to NE). Nivolumab failed to demonstrate efficacy in the non-ACC cohort (NPR6m: 14.0%; 7/50 patients). ORR, PFS and OS were 8.7% (95% CI 2.4 to 20.8), 5.3 (95% CI 3.2 to 5.6) and 17.2 months (95% CI 12.5-NE) in the ACC cohort, and 3.8% (95% CI 0.5 to 13.2), 1.8 (95% CI 1.7 to 3.5) and 11.5 months (95% CI 7.5 to 14.8) in the non-ACC cohort. Nivolumab safety profile was consistent with previous reports.

Conclusion

Nivolumab has limited efficacy in SGC. Differential results were observed in the two cohorts. The primary endpoint was met in the ACC cohort and no new safety signals were identified.

Trial registration number

EudraCT number: 2016-001794-32/NCT03132038.

The clinical significance for primary tumor surgery in metastatic head and neck adenoid cystic carcinoma

PURPOSE

This study aimed to determine the prognostic significance and optimal candidates for primary tumor surgery (PTS) among patients with metastatic head and neck adenoid cystic carcinoma (HNACC).

METHODS

The data were retrieved from Surveillance, Epidemiology, and End Results (SEER) database. Patients with metastatic HNACC at the initial diagnosis were included in this study. Univariate survival analysis was performed using the Kaplan-Meier method, and the difference in survival curves between PTS and non-PTS groups was estimated using the log-rank test. Multivariate analysis was performed to evaluate the independent prognostic factors associated with overall survival (OS) and cancer-specific survival (CSS).

RESULTS

Overall, 155 patients were eligible, of whom 93 underwent palliative PTS. Patients with lung metastasis alone were more likely to undergo PTS. PTS was associated with significantly improved OS and CSS compared with non-PTS. In the multivariate model, patients who underwent PTS had better OS than those who did not undergo PTS; however, no improvement was observed in the CSS. Subgroup analyses further revealed that patients aged < 60 years with T3-4 or N0 classification might benefit from PTS.

CONCLUSION

PTS significantly improved the OS of patients with metastatic HNACC. PTS had a favorable prognostic impact on highly selected patients, namely, those aged < 60 years with T3-4 and N0 classification, which could be adopted in future clinical practice.

A Review of the Molecular Landscape of Adenoid Cystic Carcinoma of the Lacrimal Gland

Adenoid cystic carcinoma (ACC) has a worldwide incidence of three to four cases per million population. Although more cases occur in the minor and major salivary glands, it is the most common lacrimal gland malignancy. ACC has a low-grade, indolent histological appearance, but is relentlessly progressive over time and has a strong proclivity to recur and/or metastasise. Current treatment options are limited to complete surgical excision and adjuvant radiotherapy. Intra-arterial systemic therapy is a recent innovation. Recurrent/metastatic disease is common due to perineural invasion, and it is largely untreatable as it is refractory to conventional chemotherapeutic agents. Given the rarity of this tumour, the molecular mechanisms that govern disease pathogenesis are poorly understood. There is an unmet, critical need to develop effective, personalised targeted therapies for the treatment of ACC in order to reduce morbidity and mortality associated with the disease. This review details the evidence relating to the molecular underpinnings of ACC of the lacrimal gland, including the MYB-NFIB chromosomal translocations, Notch-signalling pathway aberrations, DNA damage repair gene mutations and epigenetic modifications.

MicroRNAs as the pivotal regulators of cisplatin resistance in head and neck cancers

Although, there is a high rate of good prognosis in early stage head and neck tumors, about half of these tumors are detected in advanced stages with poor prognosis. A combination of chemotherapy, radiotherapy, and surgery is the treatment option in head and neck cancer (HNC) patients. Although, cisplatin (CDDP) as the first-line drug has a significant role in the treatment of HNC patients, CDDP resistance can be observed in a large number of these patients. Therefore, identification of the molecular mechanisms involved in CDDP resistance can help to reduce the side effects and also provides a better therapeutic management. MicroRNAs (miRNAs) as the post-transcriptional regulators play an important role in drug resistance. Therefore, in the present review we investigated the role of miRNAs in CDDP response of head and neck tumors. It has been reported that the miRNAs exerted their roles in CDDP response by regulation of signaling pathways such as WNT, NOTCH, PI3K/AKT, TGF-β, and NF-kB as well as apoptosis, autophagy, and EMT process. The present review paves the way to suggest a non-invasive miRNA based panel marker for the prediction of CDDP response among HNC patients. Therefore, such diagnostic miRNA based panel marker reduces the CDDP side effects and improves the clinical outcomes of these patients following an efficient therapeutic management.

Molecular Biology and Therapeutic Targets of Primitive Tracheal Tumors: Focus on Tumors Derived by Salivary Glands and Squamous Cell Carcinoma

Primary tracheal tumors are rare, constituting approximately 0.1-0.4% of malignant diseases. Squamous cell carcinoma (SCC) and adenoid cystic carcinoma (ACC) account for about two-thirds of these tumors. Despite most primary tracheal cancers being eligible for surgery and/or radiotherapy, unresectable, recurrent and metastatic tumors may require systemic treatments. Unfortunately, the poor response to available chemotherapy as well as the lack of other real therapeutic alternatives affects the quality of life and outcome of patients suffering from more advanced disease. In this condition, target therapy against driver mutations could constitute an alternative to chemotherapy, and may help in disease control. The past two decades have seen extraordinary progress in developing novel target treatment options, shifting the treatment paradigm for several cancers such as lung cancer. The improvement of knowledge regarding the genetic and biological alterations, of major primary tracheal tumors, has opened up new treatment perspectives, suggesting the possible role of biological targeted therapies for the treatment of these rare tumors. The purpose of this review is to outline the state of knowledge regarding the molecular biology, and the preliminary data on target treatments of the main primary tracheal tumors, focusing on salivary-gland-derived cancers and squamous cell carcinoma.

Inverse agonists of retinoic acid receptor/retinoid X receptor signaling as lineage-specific antitumor agents against human adenoid cystic carcinoma

BACKGROUND

Adenoid cystic carcinoma (ACC) is a lethal malignancy of exocrine glands, characterized by the coexistence within tumor tissues of 2 distinct populations of cancer cells, phenotypically similar to the myoepithelial and ductal lineages of normal salivary epithelia. The developmental relationship linking these 2 cell types, and their differential vulnerability to antitumor treatments, remains unknown.

METHODS

Using single-cell RNA sequencing, we identified cell-surface markers (CD49f, KIT) that enabled the differential purification of myoepithelial-like (CD49fhigh/KITneg) and ductal-like (CD49flow/KIT+) cells from patient-derived xenografts (PDXs) of human ACCs. Using prospective xenotransplantation experiments, we compared the tumor-initiating capacity of the 2 cell types and tested whether one could differentiate into the other. Finally, we searched for signaling pathways with differential activation between the 2 cell types and tested their role as lineage-specific therapeutic targets.

RESULTS

Myoepithelial-like cells displayed higher tumorigenicity than ductal-like cells and acted as their progenitors. Myoepithelial-like and ductal-like cells displayed differential expression of genes encoding for suppressors and activators of retinoic acid signaling, respectively. Agonists of retinoic acid receptor (RAR) or retinoid X receptor (RXR) signaling (all-trans retinoic acid, bexarotene) promoted myoepithelial-to-ductal differentiation, whereas suppression of RAR/RXR signaling with a dominant-negative RAR construct abrogated it. Inverse agonists of RAR/RXR signaling (BMS493, AGN193109) displayed selective toxicity against ductal-like cells and in vivo antitumor activity against PDX models of human ACC.

CONCLUSIONS

In human ACCs, myoepithelial-like cells act as progenitors of ductal-like cells, and myoepithelial-to-ductal differentiation is promoted by RAR/RXR signaling. Suppression of RAR/RXR signaling is lethal to ductal-like cells and represents a new therapeutic approach against human ACCs.

A comparison of two chemotherapy regimens in advanced, recurrent, or metastatic salivary gland carcinoma

BACKGROUND

The efficacy of chemotherapy in locally advanced, recurrent, and metastatic salivary gland carcinomas (LA-R/M SGCs) is still undefined. We aimed to compare the efficacy of two chemotherapy regimens in LA-R/M SGC.

MATERIALS AND METHODS

This prospective study compared paclitaxel (Taxol) plus carboplatin (TC) versus cyclophosphamide, doxorubicin, plus cisplatin (CAP) regimen in terms of overall response rate (ORR), clinical benefit rate (CBR), progression-free survival (PFS), and overall survival (OS).

RESULTS

Between October 2011 and April 2019, 48 patients with LA-R/M SGCs were recruited. The ORRs of first-line TC and CAP regimens were 54.2% and 36.3%, respectively (P = 0.57). The ORRs in recurrent and de novo metastatic patients were 50.0% and 37.5% for TC and CAP, respectively (P = 0.26). The median PFS of TC and CAP arms were 10.2 and 11.9 months, respectively (P = 0.91). In the subanalysis, patients with adenoid cystic carcinoma (ACC) had longer PFS in the TC arm (14.5 vs. 8.2 months, P = 0.03), irrespective of the tumor grade (low grade: 16.3 vs. 8.9 months, high grade: 11.7 vs. 4.5 months; P = 0.03). The median OS rates were 45.5 and 19.5 months for TC and CAP groups, respectively (P = 0.71).

CONCLUSION

For patients with LA-R/M SGC, there was no significant difference between first-line TC and CAP in terms of ORR, PFS, and OS.

Retrospective study of outcomes after extended resection for tracheobronchial adenoid cystic carcinoma

OBJECTIVE

Tracheobronchial adenoid cystic carcinoma is a rare, slow-growing malignancy with a considerable propensity for local extension that may require complex airway resection to achieve tumor-free margins. The objective of this study was to assess whether our experience supports complex airway resection for tracheobronchial adenoid cystic carcinoma.

METHODS

Consecutive patients who underwent curative resection for tracheobronchial adenoid cystic carcinoma at our institution between 1970 and 2019 were included retrospectively and classified as having had complex or standard resection. Complex surgery included total tracheal replacement, associated esophageal resection, pneumonectomy, total laryngectomy with tracheal resection, and carinal resection. Standard surgery included tracheal resection, bronchoplastic resection, lobectomy, and bilobectomy. We obtained data from medical records, referring physicians, patients, relatives, and public death records.

RESULTS

Of 59 included patients, 38 had complex and 21 had standard surgery. All 4 (6.8%) patients who died postoperatively had undergone complex surgery. Postoperative morbidity was 32.2% overall and was significantly higher after complex surgery (P = .043). Overall 5- and 10-year survival rates were 81.5% and 60.2%, with no significant differences between groups (P = .31). By univariate analysis, T4 tumor and microscopically detectable tumor in the operative specimen margins and gross tumor in the operative specimen margins were associated with poorer survival (P < .05). In the subgroup with microscopically detectable tumor resection, survival was significantly better with adjuvant radiotherapy (P < .05).

CONCLUSIONS

Complex resection for extended tracheobronchial adenoid cystic carcinoma may achieve local control and satisfying long-term survival. However, this demanding procedure is associated with high postoperative morbidity and mortality rates. Because adjuvant radiotherapy improved outcomes after resection resulting in microscopically detectable tumor in the operative specimen margins, expected outcomes after resection with no detectable tumor in the margins must be compared to those after resection resulting in microscopically detectable tumor in the margins plus radiotherapy, according to the operative risk.

Unraveling the Role of Epithelial-Mesenchymal Transition in Adenoid Cystic Carcinoma of the Salivary Glands: A Comprehensive Review

Salivary adenoid cystic carcinoma (SACC) is considered a challenging malignancy; it is characterized by a slow-growing nature, yet a high risk of recurrence and distant metastasis, presenting significant hurdles in its treatment and management. At present, there are no approved targeted agents available for the management of SACC and systemic chemotherapy protocols that have demonstrated efficacy remain to be elucidated. Epithelial-mesenchymal transition (EMT) is a complex process that is closely associated with tumor progression and metastasis, enabling epithelial cells to acquire mesenchymal properties, including increased mobility and invasiveness. Several molecular signaling pathways have been implicated in the regulation of EMT in SACC, and understanding these mechanisms is crucial to identifying new therapeutic targets and developing more effective treatment approaches. This manuscript aims to provide a comprehensive overview of the latest research on the role of EMT in SACC, including the molecular pathways and biomarkers involved in EMT regulation. By highlighting the most recent findings, this review offers insights into potential new therapeutic strategies that could improve the management of SACC patients, especially those with recurrent or metastatic disease.

A Case of Primary Intraosseous Adenoid Cystic Carcinoma of the Mandible

Primary intraosseous adenoid cystic carcinoma (PIACC) of the jaw is rare. To our knowledge, only 51 cases have been reported in the English literature. We present a rare case of PIACC arising in the mandible with multiple bone metastases and review the previous articles. A 70-year-old woman presented with paresthesia of the right chin and lower gingiva for 4 months. Radiography revealed an irregular radiolucent region on the right side of the ramus, infiltrating to the mandibular canal. Biopsy revealed a pathological diagnosis of adenoid cystic carcinoma. Multiple bone metastases were present in the sternum, scapula, and thighs. The treatment effect was progressive disease for chemotherapy; therefore, best supportive care was provided for 3 years.

Phase II Clinical Trial of Axitinib and Avelumab in Patients With Recurrent/Metastatic Adenoid Cystic Carcinoma

PURPOSE

We conducted a phase II trial evaluating the efficacy of VEGFR inhibitor axitinib and PD-L1 inhibitor avelumab in patients with recurrent/metastatic adenoid cystic carcinoma (R/M ACC).

PATIENTS AND METHODS

Eligible patients had R/M ACC with progression within 6 months before enrollment. Treatment consisted of axitinib and avelumab. The primary end point was objective response rate (ORR) per RECIST 1.1; secondary end points included progression-free survival (PFS), overall survival (OS), and toxicity. Simon's optimal two-stage design tested the null hypothesis of ORR ≤5% versus ORR ≥20% at 6 months; ≥4 responses in 29 patients would reject the null hypothesis.

RESULTS

Forty patients enrolled from July 2019 to June 2021; 28 were evaluable for efficacy (six screen failures; six evaluable for safety only). The confirmed ORR was 18% (95% CI, 6.1 to 36.9); there was one unconfirmed partial response (PR). Two patients achieved PR after 6 months; thus, the ORR at 6 months was 14%. The median follow-up time for surviving patients was 22 months (95% CI, 16.6 to 39.1 months). The median PFS was 7.3 months (95% CI, 3.7 to 11.2 months), 6-month PFS rate was 57% (95% CI, 41 to 78), and median OS was 16.6 months (95% CI, 12.4 to not reached months). Most common treatment-related adverse events (TRAEs) included fatigue (62%), hypertension (32%), and diarrhea (32%). Ten (29%) patients had serious TRAEs, all grade 3; four patients (12%) discontinued avelumab, and nine patients (26%) underwent axitinib dose reduction.

CONCLUSION

The study reached its primary end point with ≥4 PRs in 28 evaluable patients (confirmed ORR of 18%). The potential added benefit of avelumab to axitinib in ACC requires further investigation.

Single-cell RNA sequencing reveals the heterogeneity and microenvironment in one adenoid cystic carcinoma sample

Adenoid cystic carcinoma (ACC) is one of the most common malignancy of the major salivary glands with a high recurrence rate and poor prognosis. Determining tumor heterogeneity and factors in the microenvironment may provide novel therapeutic targets for ACC. We performed single-cell RNA sequencing of one ACC sample and normal salivary gland tissues from a patient to analyze tumor heterogeneity, immunosuppressive landscape, and intercellular communication networks. The heterogeneity of epithelial cells in ACC tissues was significantly higher compared with that in normal tissues, whereas immune cells were almost absent. We found four malignant cell clusters in ACC and explored their characteristics and function. In tumor tissues, CD8 + cytotoxic T cells and CD4 + T helper cells were significantly decreased, whereas IgA + plasma cells were absent. There were two clusters of macrophages, one representing IL1B macrophages and the other consisted of a cluster of macrophages associated with the epithelial mesenchymal transition (EMT). Both were significantly different from the normal tissue composition. In addition, the communication between epithelial cells and other cells in the tumor tissue was enhanced. MIF-CD74 and APP-CD74 were significantly upregulated. We comprehensively described the heterogeneity of ACC and the tumor microenvironment (TME) from a single cell perspective including cell characteristics, immune cell infiltration, and cell communication. CLINICAL RELEVANCE: This study provided further insights into ACC and may lead to new treatment strategies.

Current trends in the treatment of recurrent adenocystic cancer of the salivary glands: case report

Salivary gland carcinomas is a rare family of neoplasms with different histological characteristics and biological behavior. Treatment regimens have remained virtually unchanged for decades, leaving the leading role for surgical treatment and radiation therapy. However, a special place in the salivary gland carcinomas group is occupied by adenoid cystic carcinoma, which is quite often characterized by a recurrent and / or metastatic course with the use of chemotherapy as the main option in treatment. It is worth noting the fact that the results of standard chemotherapy regimens show unsatisfactory results, respectively, with recurrent or metastatic adenoid cystic carcinoma, treatment options are minimal. Accordingly, there is a need to study new therapeutic methods for the treatment of this disease. In this situation, high hopes were placed on targeted therapy, in particular, the family of epidermal growth factor receptors, c-Kit are the most frequently studied molecular targets. Due to the rare occurrence of adenoid cystic carcinoma, the number of cases of using targeted therapy for analysis is relatively small, so each clinical observation is of particular value. The following is a clinical case of treatment of recurrent adenoid cystic carcinoma using a personalized treatment approach.

Aim. To describe the clinical observation of the use of targeted drugs in recurrent or metastatic adenocystic cancer of the salivary glands.