Salivary gland adenoid cystic carcinoma: A review of chemotherapy and molecular therapies

Post-operative radiotherapy in adenoid cystic carcinoma of salivary glands versus surgery alone: what is the evidence about survival and local control? A systematic review and meta-analysis

BACKGROUND

Adenoid cystic carcinoma of the salivary glands is a relatively rare malignancy characterized by slow growth and a poor prognosis, and effective treatments remain challenging to identify. This systematic review, following the PRISMA guidelines, aimed to analyze the potential benefits of post-operative radiotherapy in terms of local control of recurrences and survival advantages when compared with surgery alone in patients with adenoid cystic carcinoma.

METHODS

A comprehensive systematic review was conducted by searching the MEDLINE, Cochrane, EMBASE, and OVID databases from January 1999 to July 2022. The goal was to identify articles comparing surgery alone with surgery plus postoperative radiotherapy for adenoid cystic carcinoma of the salivary glands. Downs and Black Checklist was used to assess the methodological quality and risk of bias of each included study. The data analysis was performed using Review Manager version 5.4.1.

RESULTS

This review included 8 studies comprising a total of 3103 patients, divided based on the analyzed outcomes. The pooled odds ratio for overall survival at 5 years was 0.87 (95% confidence interval 0.43-1.76, p = 0.70), and at 10 years was 1.23 (95% confidence interval 0.69-2.16, p = 0.48). In both cases, no statistically significant differences were observed. However, the pooled odds ratio for local control at 5 years was 3.37 (95% confidence interval 1.35-8.42, p = 0.009), providing strong support for the use of post-operative radiation.

CONCLUSIONS

The findings from the meta-analysis suggest that post-operative radiotherapy significantly improves local control in patients with adenoid cystic carcinoma. However, there was no statistically significant increase in survival at 5 and 10 years. It is essential to note that the quality of the studies included in this meta-analysis ranged from fair to poor. To better clarify the indications for post-operative radiotherapy, future high-quality research is needed, particularly with improved stratification of patient groups. Additionally, it is important to recognize that achieving local control in adenoid cystic carcinoma is crucial for enhancing the overall quality of life for patients. We acknowledge that this review was not registered in the PROSPERO database, and the data pooling was conducted using a random effects model.

Artificial intelligence-powered spatial analysis of tumor-infiltrating lymphocytes as a predictive biomarker for axitinib in adenoid cystic carcinoma

BACKGROUND

This study analyzed the predictive value of artificial intelligence (AI)-powered tumor-infiltrating lymphocyte (TIL) analysis in recurrent or metastatic (R/M) adenoid cystic carcinoma (ACC) treated with axitinib.

METHODS

Patients from a multicenter, prospective phase II trial evaluating axitinib efficacy in R/M ACC were included in this study. H&E whole-side images of archival tumor tissues were analyzed by Lunit SCOPE IO, an AI-powered spatial TIL analyzer.

RESULTS

Twenty-seven patients were included in the analysis. The best response was stable disease, and the median progression-free survival (PFS) was 11.1 months (95% CI, 9.2-13.7 months). Median TIL densities in the cancer and surrounding stroma were 25.8/mm2 (IQR, 8.3-73.0) and 180.4/mm2 (IQR, 69.6-342.8), respectively. Patients with stromal TIL density >342.5/mm2 exhibited longer PFS (p = 0.012).

CONCLUSIONS

Cancer and stromal area TIL infiltration were generally low in R/M ACC. Higher stromal TIL infiltration was associated with a longer PFS with axitinib treatment.

FNIII14 Peptide-Enriched Membrane Nanocarrier to Disrupt Stromal Barriers through Reversing CAFs for Augmenting Drug Penetration in Tumors

Given the key roles of cancer associated fibroblasts (CAFs) in shaping tumor stroma, this study shows a CAF-associated ITGB1-inactivating peptide-enriched membrane nanodelivery system (designated as PMNPs-D) to simultaneously target CAFs and tumor cells for boosted chemotherapy through promoted drug perfusion. In the structure of PMNPs-D, the PLGA-based inner core is loaded with the chemotherapeutic drug doxorubicin, and the outer surface is cloaked by hybrid biomembranes with the insertion of integrin β1 (ITGB1) inhibiting peptide (i.e., FNIII14). After prolonged blood circulation and actively targeting in tumor sites, PMNPs-D can respond to CAF-overexpressed fibroblast activation protein-α (FAP-α) to trigger the release of FNIII14, which will bind to ITGB1 and inhibit CAFs' biological function in producing the stromal matrix, thereby loosening the condensed stromal structure and enhancing the permeability of nanotherapeutics in tumors. As a result, this tailor-designed nanosystem shows substantial tumor inhibition and metastasis retardation in aggressive adenoid cystic carcinoma (ACC) tumor-harboring mice.

Comparison of 68Ga-PSMA-HBED-CC and 18F-FDG PET/CT in the Evaluation of Adenoid Cystic Carcinoma-A Prospective Study

PURPOSE OF STUDY

18F-FDG PET/CT plays a major role in diagnosis and staging of head and neck cancer; however, FDG has lower uptake in adenoid cystic carcinoma (AdCC). Prostate-specific membrane antigen (PSMA) expression is found to be associated with endothelial cells or tumor neovasculature in malignant AdCC and salivary duct carcinoma. Thus, present study is aimed to compare the role of 68Ga-PSMA and 18F-FDG PET/CT in patients with primary and/or metastatic AdCC.

MATERIALS AND METHODS

Histopathologically proven AdCC patients were intravenously injected with 370 MBq (10 mCi) of 18F-FDG and 111-185 MBq (3-5 mCi) of 68Ga-PSMA. Images were acquired at 60 and 45 minutes postinjection for 18F-FDG and 68Ga-PSMA, respectively, on dedicated PET/CT scanners. Visual and semiquantitative analyses of PSMA expression in regional and metastatic sites were performed by 2 experienced nuclear medicine physicians.

RESULTS

Seventeen patients (7 men, 10 women) having mean age of 44 ± 14.19 years were prospectively included in the study. Of 17 patients, FDG PET/CT was performed in only 14 (82%) patients. PSMA and FDG uptakes were seen at the primary site in 16 (94%) and 13 (93%) patients, respectively, whereas 1 patient was postradical tumor excision. Lung lesions (n = 7) and lymph nodes (n = 5) were detected on both FDG and PSMA PET scans. However, cerebellar and meningeal metastasis (n = 1, 6%) and bony lesions (n = 2, 12%) were detected only on PSMA PET/CT but not visualized on FDG PET/CT scan.

CONCLUSIONS

PSMA may have theranostic importance in unresectable or metastatic AdCC, besides having a role in staging/restaging.

Epidemiology of and factors associated with overall survival for patients with head and neck adenoid cystic carcinoma

BACKGROUND

Updated epidemiologic and survival data of head and neck adenoid cystic carcinoma (HNACC) are lacking. This retrospective study aimed to clarify the incidence, prevalence, and overall survival (OS) of patients with HNACC and establish relevant nomogram.

METHODS

Trends in incidence, limited-duration prevalence, and relative survival (RS) rates were evaluated using data from the Surveillance, Epidemiology, and End Results (SEER) database, and annual percent change (APC) in rates was calculated using joinpoint regression. Data on age, sex, site, stage, and surgery were used in construction and validation of the nomogram.

RESULTS

The study included 6474 patients; 57.7% were female and 78.6% were white. The age-adjusted incidence rates of HNACC decreased significantly from 0.41 to 0.25 per 100,000 [1975-2018; average annual percent change (AAPC): - 1.37, P < 0.001], which was dominated by the localized stage. The 20-year limited duration prevalence increased from 0.00028% to 0.00262%. The 5- and 10-year RS rates of all HNACC patients were 80.0% and 65.5%, respectively. RS rates in HNACC showed a slight increase over time, with APC values of 0.03 for 5-year (P < 0.05) and 0.13 for 10-year (P < 0.05) RS. A prognostic model was constructed. The C-indices for the training and testing sets were both 0.734. The nomogram's discrimination efficiency was evaluated using the receiver operating characteristic curve and had moderate predictive power.

CONCLUSIONS

Over the past 40 years, the incidence of HNACC decreased accompanied by slightly improved survival rates. Nomogram was capable of predicting the 5- and 10-year OS rates with moderate accuracy.

Successful Treatment with Definitive Concurrent Chemoradiotherapy Followed by Durvalumab Maintenance Therapy in a Patient with Tracheal Adenoid Cystic Carcinoma

Adenoid cystic carcinoma (ACC) is a rare type of malignant tracheal tumor originating from the secretory glands. Complete surgical resection is the current standard of care for tracheal ACC. However, there have been few case reports of chemoradiotherapy for unresectable tracheal ACC. We herein report a 28-year-old man with unresectable tracheal ACC who received concurrent chemoradiotherapy (CCRT) followed by maintenance therapy with durvalumab. CCRT was completed with a good response and safety, and the patient is currently receiving durvalumab as maintenance therapy. Durvalumab after CCRT can be a treatment option for patients with unresectable tracheal ACC.

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.

Therapeutic inhibition of Bmi-1 ablates chemoresistant cancer stem cells in adenoid cystic carcinoma

OBJECTIVES

Adenoid Cystic Carcinomas (ACC) typically show modest responseto cytotoxic therapy. Cancer stem cells (CSC) have been implicated in chemoresistance and tumor relapse. However, their role in ACC remains unknown. The purpose of this work was to evaluate the impact of targeting ACC CSCs with Bmi-1 inhibitors on resistance to cytotoxic therapy and tumor relapse.

MATERIALS AND METHODS

Therapeutic efficacy of a small molecule inhibitor of Bmi-1 (PTC596; Unesbulin) and/or Cisplatin on ACC stemness was evaluated in immunodeficient mice harboring PDX ACC tumors (UM-PDX-HACC-5) and in human ACC cell-lines (UM-HACC-2A,-14) or low passage primary human ACC cells (UM-HACC-6). The effect of therapy on stemness was examined by salisphere assays, flow cytometry for ALDH activity and CD44 expression, and Western blots for Bmi-1 (self-renewal marker) and Oct4 (embryonic stem cell marker) expression.

RESULTS

Platinum-based agents (Cisplatin, Carboplatin) induced Bmi-1 and Oct4 expression, increased salisphere formation and the CSC fraction in vitro and in vivo. In contrast, PTC596 inhibited expression of Bmi-1, Oct4 and pro-survival proteins Mcl-1 and Claspin; decreased the number of salispheres, and the fraction of ACC CSCs in vitro. Silencing Claspin decreased salisphere formation and CSC fraction. Both, single agent PTC596 and PTC596/Cisplatin combination decreased the CSC fraction in PDX ACC tumors. Notably, short-term combination therapy (2 weeks) with PTC596/Cisplatin prevented tumor relapse for 150 days in a preclinical trial in mice.

CONCLUSION

Therapeutic inhibition of Bmi-1 ablates chemoresistant CSCs and prevents ACC tumor relapse. Collectively, these results suggest that ACC patients might benefit from Bmi-1-targeted therapies.

Salivary gland cancer organoids are valid for preclinical genotype-oriented medical precision trials

Salivary gland cancers (SGCs) are heterogeneous tumors, and precision oncology represents a promising therapeutic approach; however, its impact on SGCs remains obscure. This study aimed to establish a translational model for testing molecular-targeted therapies by combining patient-derived organoids and genomic analyses of SGCs. We enrolled 29 patients, including 24 with SGCs and 5 with benign tumors. Resected tumors were subjected to organoid and monolayer cultures, as well as whole-exome sequencing. Organoid and monolayer cultures of SGCs were successfully established in 70.8% and 62.5% of cases, respectively. Organoids retained most histopathological and genetic profiles of their original tumors. In contrast, 40% of the monolayer-cultured cells did not harbor somatic mutations of their original tumors. The efficacy of molecular-targeted drugs tested on organoids depended on their oncogenic features. Organoids recapitulated the primary tumors and were useful for testing genotype-oriented molecular targeted therapy, which is valuable for precision medicine in patients with SGCs.

Proton therapy and/or helical tomotherapy for locally advanced sinonasal skull base adenoid cystic carcinoma: Focus on experience of the Institut Curie and review of literature

BACKGROUND

Sinonasal adenoid cystic carcinomas (SNACC) have high propensity for skull base (SB) infiltration. Unresectability or incomplete surgical resection in such cases make radiotherapy treatment paramount. Curative dose escalation is challenging because of adjacent organs at risk, especially in locally advanced cases.

METHODS

Eighteen patients that had locally advanced SB SNACC with unresectable or incomplete surgical resection treated by proton therapy and/or helical tomotherapy at Institut Curie between 3/2010 and 8/2020 were retrospectively included.

RESULTS

After median follow-up of 52 months, 5-year OS, LRRFS, DMFS, DFS rates were, respectively, 47% (95%CI: 26-83), 50% (95%CI: 36-88), 39% (95%CI: 26-81), 33% (95%CI: 22-73). One patient had grade 4 late optic nerve disorder. Eight patients had grade 3 late toxicity including mainly hearing impairments.

CONCLUSION

Proton therapy and helical tomotherapy are effective and safe methods for curative dose escalation of locally advanced SB SNACC, which are a poor prognosis subgroup. Available literature suggests carbon-ion therapy could be an efficient alternative.

The Epigenesis of Salivary Glands Carcinoma: From Field Cancerization to Carcinogenesis

Salivary gland carcinomas (SGCs) are a diverse collection of malignant tumors with marked differences in biological activity, clinical presentation and microscopic appearance. Although the etiology is varied, secondary radiation, oncogenic viruses as well as chromosomal rearrangements have all been linked to the formation of SGCs. Epigenetic modifications may also contribute to the genesis and progression of SGCs. Epigenetic modifications are any heritable changes in gene expression that are not caused by changes in DNA sequence. It is now widely accepted that epigenetics plays an important role in SGCs development. A basic epigenetic process that has been linked to a variety of pathological as well as physiological conditions including cancer formation, is DNA methylation. Transcriptional repression is caused by CpG islands hypermethylation at gene promoters, whereas hypomethylation causes overexpression of a gene. Epigenetic changes in SGCs have been identified, and they have been linked to the genesis, progression as well as prognosis of these neoplasms. Thus, we conduct a thorough evaluation of the currently known evidence on the involvement of epigenetic processes in SGCs.

Recent Advances, Systemic Therapy, and Molecular Targets in Adenoid Cystic Carcinoma of the Head and Neck

With an incidence of 3-4.5 cases per million, adenoid cystic carcinoma (ACC) of the head and neck is one of the most common tumors of the parotid and sublingual salivary glands. In the clinical course, ACC is shown to have an aggressive long-term behavior, which leads to the fact that radical surgical resection of the tumor with tumor-free margins remains the "gold standard" in treating ACC. Particle radiation therapy and systemic molecular biological approaches offer new treatment options. However, risk factors for the formation and prognosis of ACC have not yet been clearly identified. The aim of the present review was to investigate long-term experience of diagnosis and treatment as well as risk and prognostic factors for occurrence and outcome of ACC.

Combined all-trans retinoic acid with low-dose apatinib in treatment of recurrent/metastatic head and neck adenoid cystic carcinoma: A single-center, secondary analysis of a phase II study

BACKGROUND

Treatment options are limited for recurrent/metastatic adenoid cystic carcinoma of the head and neck (R/M ACCHN). We aimed to evaluate the preliminary results of the efficacy and safety of all-trans retinoic acid (ATRA) combined with low-dose apatinib in patients with R/M ACCHN according to a secondary analysis of a phase II study.

METHODS

Patients from a phase II study (NCT02775370) who orally administered 500 milligram (mg) apatinib daily until treatment-related adverse events (AEs) intolerance or progression occurred were eligible for inclusion. Patients were further treated with combination therapy of ATRA (25 mg/m² /day) and apatinib (250 mg/day) between March 2019 and October 2021 until progression of disease (PD).

RESULTS

A total of 16 patients were included with nine (56.3%) males and aged 35-69 years old. All recruited patients previously received anti-angiogenic therapy then withdrew due to toxicities or progression occurred. The objective response rate (ORR) and disease control rate (DCR) were 18.8% and 100%, respectively. During a median follow-up of 23.9 months (range:17.8-31.7 months), 11 (68.8%) patients developed PD and one of them died in 20.9 months. The median of progression-free survival (PFS) was 16.3 months (95% CI: 7.2-25.4 months), and the 6-month, 12-month, and 24-month PFS rates were 100%, 81.3%, and 33.3%, respectively. The grade 3 adverse events were albuminuria (n = 2, 12.5%) and hand-foot syndrome (n = 1, 6.25%).

CONCLUSION

All-trans retinoic acid combined with low-dose apatinib might be a potential efficacy therapeutic option for patients with R/M ACCHN. This finding will be further confirmed by our registered ongoing trial, the APLUS study (NCT04433169).

Analysis of Cytological Misdiagnosis and Oversight of Adenoid Cystic Carcinoma of Salivary Gland

OBJECTIVE

In this article on adenoid cystic carcinoma (ACC) of salivary gland, we intend to summarize the causes of misdiagnosis and oversight of ACC hoping to improve cytological diagnostic accuracy, clinical management and patient treatment.

METHODS

The study retrospectively reviewed 32 patients with ACC of salivary gland, registered at the Affiliated Hospital of Southwest Medical University from July 2014 to June 2021. These cases were diagnosed by FNA and surgical excision biopsy. All cytopathological results were retrospectively categorized according to Milan system for reporting salivary gland cytopathology (MSRSGC). The accuracy of FNA was verified by surgical excision biopsy.

RESULTS

Of these 32 patients, 16 (50.0%) cases were male, and 16 (50.0%) were female. Their age ranged from 21 to 79 years, with an average age of 50.32 years. The highest incidence (15/32, 46.9%) of ACC was observed in patients between 41 and 50 years of age. 10 cases (31.3%) occurred in the parotid gland, 9 cases (28.1%) in the submandibular gland, 9 cases (28.1%) in the sublingual gland, 3 cases (9.4%) in the palate, and 1 case (3.1%) in the lip. Among the 32 cases of ACC, 23 cases (71.9%) were classified to VI, 4 cases (12.5%) to IVa, and 5 cases (15.6%) to II by MSRSGC. A comparison of the FNA results with biopsy showed that the accuracy of FNA in ACC of salivary gland is 71.9%. Being able to identify the cytomorphological features is the key factor for accurate diagnosis of ACC of the salivary gland.

CONCLUSION

Our results confirm that FNA is an important initial screening in the diagnosis of ACC of salivary gland. Increased study of the cytomorphology of ACC is beneficial for more accurate diagnosis of ACC, to reduce misdiagnosis and oversight.

Adenoid Cystic Carcinoma of Salivary Glands: A Ten-Year Review and an Assessment of the Current Management, Surgery, Radiotherapy, and Chemotherapy

Adenoid cystic carcinoma (ACC) is a rare cancer that arises from the salivary glands and other sites in the body, such as the lung and breast. Although the tumor accounts for 10% of all salivary gland malignancies, it only accounts for 1% of head and neck malignancies. It can affect both major and minor salivary glands; here, it is called salivary gland adenoid cystic carcinoma or SACC, with a slight predilection to the latter, and commonly manifests between the 6_th and 7_th decades of life. The disease also shows a slight female predilection, with a reported female to male ratio of 3 : 2. Lesions of SACC are often insidious and slow-growing, and symptoms such as pain and altered sensation are frequently associated with advanced stages of the disease. Salivary adenoid cystic carcinoma is characterized by perineural invasion (PNI), a distinctive feature that potentially plays a significant role in the tumor's relapse and recurrence, which is approximately 50%. The disease is not prevalent, and its etiopathogenesis is poorly understood, although several genetic patterns and biomarkers have been linked to its initiation and/or progression. The discovery of these mutations and biomarkers has encouraged several clinical studies to use therapeutic agents to target the specific receptors on the cancer cells to potentially prevent further proliferation of the tumor cells and metastasis of the disease. Diagnosis of SACC is often challenging and frequently requires a combination of clinical examination, imaging, and histopathology. Management of SACC is primarily surgical excision, while radiotherapy has shown to be effective in improving local control in cases with microscopic residual disease. However, treatment of recurrent or metastatic tumors by radiotherapy with or without chemotherapy has so far shown limited success. The aim of this thesis is to provide an update of literature on SACC with a particular focus on the latest management approaches and future trends.

Treatment of Adenoid Cystic Carcinoma of the Palate and Reconstruction of Defect With Nasoseptal Flap: A Clinical Case and Review of Literature

Adenoid cystic carcinoma (ACC) is a malignant tumor arising from the salivary glands. While surgery is the mainstay of treatment for ACC of the palate, adjuvant radiotherapy and/or chemotherapy should be considered in high-risk cases. Oronasal fistula, a complication of palatal surgery, may cause speech disturbance and food regurgitation; the nasoseptal flap is a potential option to repair this defect as it is readily available and reliable. Here, we present a case of locally advanced ACC of the palate in a patient who underwent endoscopic-assisted transoral tumor excision with nasoseptal flap reconstruction postoperative chemoradiotherapy.

The imminent role of microRNAs in salivary adenoid cystic carcinoma

Unfortunately, despite the severe problem associated with salivary adenoid cystic carcinoma (SACC), it has not been studied in detail yet. Therefore, the time has come to understand the oncogenic cause of SACC and find the correct molecular markers for diagnosis, prognosis, and therapeutic target to tame this disease. Recently, we and others have suggested that non-coding RNAs, specifically microRNAs and long non-coding RNAs, can be ideal biomarkers for cancer(s) diagnosis and progression. Herein, we have shown that various miRNAs, like miR-155, miR‑103a‑3p, miR-21, and miR-130a increase the oncogenesis process, whereas some miRNAs such as miR-140-5p, miR-150, miR-375, miR-181a, miR-98, miR-125a-5p, miR-582-5p, miR-144-3p, miR-320a, miR-187 and miR-101-3p, miR-143-3p inhibit the salivary adenoid cystic carcinoma progression. Furthermore, we have found that miRNAs also target many vital genes and pathways like mitogen-activated protein kinases-snail family transcriptional repressor 2 (MAPK-Snai2), p38/JNK/ERK, forkhead box C1 protein (FOXC1), mammalian target of rapamycin (mTOR), integrin subunit beta 3 (ITGB3), epidermal growth factor receptor (EGFR)/NF-κB, programmed cell death protein 4 (PDCD4), signal transducer and activator of transcription 3 (STAT3), neuroblastoma RAS (N-RAS), phosphatidylinositol-3-kinase (PI3K)/Akt, MEK/ERK, ubiquitin-like modifier activating enzyme 2 (UBA2), tumor protein D52 (TPD52) which play a crucial role in the regulation of salivary adenoid cystic carcinoma. Therefore, we believe that knowledge from this manuscript will help us find the pathogenesis process in salivary adenoid cystic carcinoma and could also give us better biomarkers of diagnosis and prognosis of the disease.

A curious case of metastatic parotid adenoid cystic carcinoma to kidney

A woman in her 60s presented with a 2-week history of non-specific left-sided abdominal pain. She previously underwent a total parotidectomy and adjuvant radiotherapy for left parotid adenoid cystic carcinoma 13 years prior, with a local recurrence 4 years after. Investigations revealed a large left-sided renal mass with appearances of renal carcinoma and no signs of metastatic disease. Pathology following nephrectomy revealed a metastatic adenoid cystic carcinoma.Metastatic disease recurred 11 months postradical nephrectomy to the contralateral kidney and lung, and she was referred to medical oncology for further management.This case history demonstrates the highly aggressive nature of an adenoid cystic carcinoma primary of salivary gland origin with rare metastasis to the kidney.

Adenoid Cystic Carcinoma of the Breast May Be Exempt from Adjuvant Chemotherapy

Consistent standards regarding whether postoperative adjuvant chemotherapy is required in the treatment of adenoid cystic carcinoma of the breast (ACCB) are currently lacking. Using clinical data from the Surveillance, Epidemiology, and End Results (SEER) database (1988−2015), and the National Cancer Center of China (2004−2020), we retrospectively analyzed patients with ACCB who received radical treatment. A total of 661 patients were eligible. The median age at diagnosis was 61 years; 99.5% of patients were initially diagnosed with stage I and II breast cancer, and 76.7% had triple-negative breast cancer. Only 12.4% of patients received adjuvant chemotherapy. Multivariate analysis showed that patients with lymph node metastasis and non-radiotherapy had worse overall survival (OS) (p < 0.05). Patients with lymph node metastasis, stage IIB and III, histological grade ≥ 2, and non-radiotherapy had worse breast cancer-specific survival (BCSS) (p < 0.05). Adjuvant chemotherapy did not improve the OS or BCSS. Patients treated with adjuvant chemotherapy also had no better survival outcomes after propensity score matching. External data verification confirmed that chemotherapy did not improve disease-free survival or OS. Adjuvant chemotherapy cannot improve the clinical outcomes of ACCB, even in subgroups with a high risk of recurrence and metastasis.

Low-dose radiotherapy combined with immunotherapy for suboral adenoid cystic carcinoma with bilateral lung metastasis: A case report and literature review

Adenoid cystic carcinoma (ACC) is a type of malignant tumor arising from the salivary glands. The tumor is characterized by a predilection for recurrence and metastasis. At present, there is no effective treatment for ACC complicated with lung metastasis. The present study reported on a case of suboral ACC with bilateral lung metastasis and the clinical features and treatment options were discussed based on a literature review. A 55-year-old female presented with suboral ACC accompanied with bilateral lung metastases. The main symptoms were masses in the right mandible and shortness of breath. Low-dose radiotherapy (LDRT) combined with immunotherapy were administered to control lung metastases. The patient is currently in a stable condition and is receiving immunotherapy. LDRT combined with immunotherapy is a feasible treatment option for such patients. Our experience with this case and the information from the literature review provide insight into the therapeutic approach for this relatively rare entity.

Is prophylactic neck irradiation indicated for patients with cN0 Adenoid cystic carcinoma of the paranasal sinuses?

PURPOSE

To study the prevalence of nodal metastases in sinonasal adenoid cystic carcinoma (SNACC) and to evaluate whether prophylactic neck irradiation (PNI) should be performed in patients with clinical N0 (cN0) disease.

PATIENTS AND METHODS

Between April 1992 and November 2020, 166 patients with SNACC who had undergone radiotherapy at our department were retrospectively analyzed. The median follow-up time was 71.3 months.

RESULTS

Among 166 cases of SNACC, a total of 13 (7.8%) had retropharyngeal or cervical nodal metastasis and 93% (12/13) cases occurred in patients with advanced T stage (T3-T4). Levels VIIa, Ib, and IIa were the most common sites of initial nodal involvement. Only 1.2% (2/166) of patients presented late neck recurrence. Lymph node metastasis independently predicted a poor progression-free survival (PFS) (P = 0.017) but had no impact on overall survival (OS) (P = 0.38). PNI was performed on 36% (55/153) of cN0 patients. The OS (P = 0.42), PFS (P = 0.59), nodal recurrence-free survival (NRFS) (P = 0.46) and distant metastasis-free survival (DMFS) (P = 0.63) rates showed no significant difference between cases with and without PNI. Furthermore, cN0 patients with T4b (P = 0.53; P = 0.61), tumor origin from maxillary sinus (P = 0.55; P = 0.53) or nasopharynx involvement (P = 0.56; P = 0.60) showed no extended OS or PFS associated with PNI.

CONCLUSIONS

Regardless of the T stage or the site of origin, prophylactic neck irradiation (PNI) for cN0 patients did not provide any benefit on OS and PFS, suggesting that its application on such patients is not warranted unless there is clinical suspicion.

The anti-tumor effect of proteasome inhibitor MG132 for human adenoid cystic carcinoma: correlate with the emerging role of Nrf2/Keap1 signaling pathway

BACKGROUND

Adenoid cystic carcinoma (ACC) is one of the most common malignant salivary gland tumors. Moreover, the unique biological characteristics and complex structures of ACC contribute to its poor survival rates. Recently, proteasome inhibitors have been shown to elicit satisfactory therapeutic effects in the treatment of certain solid tumors, but few studies have been implemented to investigate the effects of proteasome inhibitor therapy for ACC.

METHODS

In this present study, cell counting kit-8 assay and flow cytometry assay were performed to examine the effects of proteasome inhibitor (MG132) on cell viability and apoptosis. We applied western blot and immunofluorescence staining to explore the expression of the Nrf2/Keap1 signaling pathway and P62, additionally Nrf2 inhibitor (ML385) was utilized to evaluate the role of Nrf2/Keap1 signaling pathway in MG132-induced cell apoptosis.

RESULTS

Our data indicated that MG132 significantly suppressed the growth of ACC-83 cells(MG132 10µM P = 0.0046; 40µM P = 0.0033; 70µM P = 0.0007 versus control) and induced apoptosis (MG132 10µM P = 0.0458; 40µM P = 0.0018; 70µM P = 0.0087 versus control). The application of MG132 induced the up-regulation of Nrf2/Keap1 signaling pathway. Furthermore, inhibition of Nrf2 attenuated the therapeutic effects of MG132 for ACC (both ML385 + MG132 10µM P = 0.0013; 40µM P = 0.0057; 70µM P = 0.0003 versus MG132). P < 0.05 was considered statistically significant.

CONCLUSIONS

Our results revealed that proteasome inhibitors MG132 could inhibit the cell viability and induce the apoptosis of ACC through Nrf2/Keap1 signaling pathway.

Graphene-containing metal-organic framework nanocomposites for enhanced microwave ablation of salivary adenoid cystic carcinoma

Salivary adenoid cystic carcinoma (SACC), one of the most common malignant tumors in the head and neck region, is characterized by high postoperative recurrence rate and poor prognosis. Microwave (MW) ablation possesses advantages in preserving SACC patients' facial aesthetics and oral function, but unfortunately, it suffers from low therapeutic efficacy due to the limited MW-thermal efficiency. Moreover, the insufficient thermal ablation may aggravate hypoxic state in tumors, which is deleterious to the treatment of residual tumors and aggressive tumors. Hence, MW ablation has been rarely applied in treating head and neck tumors in recent years. To minimize the unfavorable outcomes and maximize the therapeutic effects of MW ablation, a MW sensitizer coupled with a self-sufficient oxygen nanoagent was employed for the first time in MW ablation to treat head and neck tumors. We prepared a graphene-containing metal-organic framework (ZIF67@Gr-PEG), which exhibited excellent MW thermal conversion ability endowed by the incorporated Gr and showed in situ oxygen generation capacity derived from the ZIF67 matrix. In an animal experiment, ZIF67@Gr-PEG-based MW ablation with a temperature up to 66.1 °C exhibited a high tumor ablation rate. More importantly, insufficient MW ablation-induced high expressions of HIF-1α and VEGF were observed in our experiment, whereas the levels of tumor hypoxia and angiogenesis were efficiently decreased in MW ablation with the assistance of ZIF67@Gr-PEG nanocomposites (NCs). Notably, our strategy for MW ablation not only evidences the great potential of ZIF67@Gr-PEG but also promotes the translation of thermotherapeutic graphene from basic research to clinical practice.

Targeted Therapy, Chemotherapy, Immunotherapy and Novel Treatment Options for Different Subtypes of Salivary Gland Cancer

Surgical resection remains the first line treatment for salivary gland cancer (SGC). In the case of locally advanced disease, surgery is followed by adjuvant radiotherapy. Surgical resection should be favored in resectable locoregional recurrent disease as well, and even the complete resection of all distant oligometastases has clinical benefit for the patients. For inoperable and disseminated metastatic disease, a multitude of systemic therapies including chemotherapy, targeted therapy, and immunotherapy are available. In this review, the current therapeutic options for inoperable recurrent or metastatic SGCs are summarized. Systemic treatment can achieve prolonged progression-free and overall survival, while the overall prognosis remains poor. Current clinical trials include only a limited number of patients and mostly combine different histologic subtypes. Additionally, no randomized controlled trial comparing different therapeutic options has been performed. In the future, further studies with a larger patient cohort and ideally only one histologic subtype are needed in order to improve the outcome for SGC patients. However, this may be difficult to accomplish due to the rarity and diversity of the disease. Additionally, molecular analyses need to be performed routinely in order to individualize treatment and to go one step further towards precision medicine.

Salivary Microbiome in Adenoid Cystic Carcinoma Detected by 16S rRNA Sequencing and Shotgun Metagenomics

Microorganisms are confirmed to be closely related to the occurrence and development of cancers in human beings. However, there has been no published report detailing relationships between the oral microbiota and salivary adenoid cystic carcinoma (SACC). In this study, unstimulated saliva was collected from 13 SACC patients and 10 healthy controls. The microbial diversities, compositions and functions were comprehensively analyzed after 16S rRNA sequencing and whole-genome shotgun metagenomic sequencing. The alpha diversity showed no significant difference between SACC patients and healthy controls, while beta diversity showed a separation trend. The SACC patients showed higher abundances of Streptococcus and Rothia, while Prevotella and Alloprevotella were more abundant in healthy controls. The prevalent KEGG pathways, carbohydrate-active enzymes, antibiotic resistances and virulence factors as well as the biomarkers in SACC were determined by functional gene analysis. Our study preliminarily investigated the salivary microbiome of SACC patients compared with healthy controls and might be the basis for further studies on novel diagnostic and treatment strategies.

The Potential Prognostic Value of a Novel Hematologic Marker Fibrinogen-to-Lymphocyte Ratio in Head and Neck Adenoid-Cystic Carcinoma

Many patients with adenoid-cystic carcinoma (ACC) experience an indolent course of disease over many years but face late recurrence, and long-term survivors are rare. Due to its infrequent occurrence, it is hard to predict outcome in these patients. The fibrinogen-to-lymphocyte ratio (FLR) was recently proposed as an outcome prognosticator in different cancer entities. We aimed to investigate its prognostic relevance in patients with head and neck ACC. This retrospective analysis was performed including all patients treated for ACC between 1998 and 2020. The FLR ratio was calculated based on pretreatment values (0-7 days). The study cohort was dichotomized based on optimized threshold value and compared for differences in outcome (overall survival (OS) and disease-free survival (DFS)). In the cohort of 39 included patients, the OS was significantly longer in the low (n = 28) compared to the high pretreatment FLR group (n = 11) (median OS 150.5 months, 95% confidence intervals (CI) 85.3-215.7 months vs. 29.4 months, 95% CI not reached; p = 0.0093). Similarly, the DFS was significantly longer in the low FLR group (median DFS 74.5 months, 95% CI 30.6-118.4 months vs. 11.0 months, 95% CI 5.1-16.9 months; p = 0.019). The FLR is an easily obtainable and simple marker and may be a valuable outcome prognosticator in patients with ACC. Further studies are needed for validation of our results.

Rapid response to radiotherapy in unresectable tracheal adenoid cystic carcinoma: A case report

BACKGROUND

Adenoid cystic carcinoma (ACC) occurs mainly in the head and neck. Tracheal ACC (TACC) is uncommon. Primary resection is recommended as the main treatment of choice, and radiotherapy is considered for residual disease in the postoperative setting. Definitive radiotherapy is an alternative approach to cure unresectable TACC. As the status of radiosensitivity in TACC is uncertain, the evidence for radiotherapy in unresectable TACC is not well established, especially in terms of the optimal dosage and its response evaluation. Herein, we report a case of locally advanced TACC.

CASE SUMMARY

A 49-year-old woman was diagnosed with TACC, which included a range of lesions arising in the upper trachea extending caudally 2 cm to 7 cm of the glottis. She was treated with definitive radiotherapy, given the low likelihood of complete resection of the disease. Due to the indolent growth and the propensity for infiltration along the airways, the scheduled radiation dose of 76 Gy in 38 fractions with 6-MV X-ray delivered by intensity-modulated radiotherapy was conducted to the primary tumor volume. After irradiation of 40 Gy, the patient’s dyspnea on exertion was dramatically relieved and bronchoscopy revealed that the previous large polypoid intra-luminal mass was significantly eliminated, with near-complete response. The patient completed two phases of scheduled radiotherapy, and acute reactions to treatment included subjective chest tightness and grade 2 esophagitis, managed medically. After 5 years of treatment, the patient is alive without recurrent disease, and there were no serious late radiation esophagus and lung damage, with only slight dysphagia without perforation and fistula.

CONCLUSION

Taken together, TACC is uncommon and the treatment of unresectable TACC is challenging. This case indicated that patients with unresectable TACC who rapidly respond to radiation may benefit from primary radical radiotherapy. Radiotherapy may be considered an effective alternative treatment modality.

Comparison of Clinical Outcomes of Definitive and Postoperative Radiotherapy for Adenoid Cystic Carcinoma of the Head and Neck: Can Definitive Radiotherapy Be a Treatment Option?

Simple Summary

Adenoid cystic carcinoma of the head and neck is a rare malignant tumor; thus, it is difficult to establish an optimal treatment based on clinical trials with a large number of enrolled patients. Retrospective analyses of a small number of cases have revealed that the standard treatment is surgical resection followed by postoperative radiotherapy, while definitive radiotherapy is considered inadequate. Previous studies have used classical techniques for radiotherapy and did not evaluate the efficacy of current radiotherapy techniques, which may have underestimated the efficacy of definitive radiotherapy. We retrospectively analyzed 44 cases of adenoid cystic carcinoma of the head and neck treated with current radiotherapy techniques. Our results show that definitive radiotherapy is comparable to surgical resection followed by postoperative radiotherapy with respect to overall survival and local control. The results suggest that definitive radiotherapy can be an effective treatment option for adenoid cystic carcinoma of the head and neck.

Abstract

Background: The standard treatment for adenoid cystic carcinoma of the head and neck is surgical resection followed by postoperative radiotherapy (PORT). Currently, definitive radiotherapy (defRT) is considered an inadequate treatment; however, its data are based on studies using classical radiotherapy techniques. Therefore, the therapeutic effects of current radiotherapy techniques have not been adequately evaluated, and it may have underestimated the efficacy of defRT. Methods: We retrospectively analyzed 44 adenoid cystic carcinoma patients treated with radiotherapy based on modern treatment techniques from 1993 to 2017. Results: Twenty-four patients underwent PORT and 20 patients underwent defRT. The 5-year overall survival rates for patients treated with PORT and defRT were 85.3% and 79.7%, respectively. The 5-year local control rates were 82.5% and 83.1%, respectively. There were no statistically significant differences in the overall survival and local control of patients treated with PORT and defRT (p = 0.4392 and p = 0.0904, respectively). Conclusion: Our results show that defRT is comparable to surgical resection followed by PORT with respect to overall survival and local control. The results suggest that defRT can be an effective treatment option for adenoid cystic carcinoma of the head and neck.

Detection of novel fusion genes by next-generation sequencing-based targeted RNA sequencing analysis in adenoid cystic carcinoma of head and neck

OBJECTIVE

Adenoid cystic carcinoma (AdCC) is a rare, indolent salivary gland tumor that is reported to be driven by fusion genes. However, MYB/MYBL1-NFIB fusions have been detected in <60% of all AdCC cases and the oncogenic driver mutations in approximately 40% of AdCC remain unknown. Our aim was to identify novel gene fusions in AdCC.

STUDY DESIGN

We investigated 20 AdCC cases using a targeted RNA sequencing panel to identify gene fusions and performed quantitative real-time reverse transcription polymerase chain reaction to assess MYB, MYBL1, and NFIB expression levels.

RESULTS

A total of 36 fusion transcripts in 15 cases were detected and validated by Sanger sequencing. The MYB-NFIB and MYBL1-NFIB fusion genes were detected in 9 and 3 cases, respectively, in a mutually exclusive manner. Furthermore, novel gene fusions, namely, NFIB-EPB41L2, MAP7-NFIB, NFIB-MCMDC2, MYBL1-C8orf34, C8orf34-NFIB, and NFIB-CASC20, were identified. Among them, NFIB-EPB41L2 and NFIB-MCMDC2 are thought to activate MYB and MYBL1 expression, respectively, through the insertion of a genomic segment in proximity to MYB and MYBL1 genes, respectively.

CONCLUSION

Six novel gene fusions other than MYB/MYBL1-NFIB were identified. The detection of novel fusion genes and investigation of the molecular mechanism will contribute to the development of novel molecular targeted therapies for this disease.

Comparative Proteomic Analysis to Investigate the Pathogenesis of Oral Adenoid Cystic Carcinoma

Adenoid cystic carcinoma (ACC) belongs to salivary gland malignancies commonly occurring in an oral cavity with a poor long-term prognosis. The potential biomarkers and cellular functions acting on local recurrences and distant metastases remain to be illustrated. Proteomics is the core content of precision medicine research, which provides accurate information for early detection of cancer, benign and malignant diagnosis, classification and personalized medication, efficacy monitoring, and prognosis judgment. To obtain a comprehensive regulation network and supply clues for the treatment of oral ACC (OACC), we utilized mass spectrometry-based quantitative proteomics to analyze the protein expression profile in paired tumor and adjacent normal tissues. We identified a total of 40,547 specific peptides and 4454 differentially expressed proteins (DEPs), in which HAPLN1 was the most upregulated protein and BPIFB1 was the most downregulated. Then, we annotated the functions and characteristics of DEPs in detail from the aspects of gene ontology, subcellular structural localization, KEGG, and protein domain to thoroughly understand the identified and quantified proteins. Glycosphingolipid biosynthesis and glycosaminoglycan degradation pathways showed the biggest difference according to KEGG analysis. Moreover, we confirmed 20 proteins from the ECM-receptor signaling pathway by a parallel reaction monitoring quantitative detection and 19 proteins were quantified. This study provides useful insights to analyze DEPs in OACC and guide in-depth thinking of the pathogenesis from a proteomics view for anticancer mechanisms and potential biomarkers.

Outcomes Following Percutaneous Microwave and Cryoablation of Lung Metastases from Adenoid Cystic Carcinoma of the Head and Neck: A Bi-Institutional Retrospective Cohort Study

OBECTIVE

The aim of this study was to report outcomes following percutaneous microwave and cryoablation of lung metastases from adenoid cystic carcinoma (ACC) of the head and neck.

MATERIAL AND METHODS

This bi-institutional retrospective cohort study included 10 patients (6 females, median age 59 years [range 28-81]) who underwent 32 percutaneous ablation sessions (21 cryoablation, 11 microwave) of 60 lung metastases (median 3.5 tumors per patient [range 1-16]) from 2007 to 2019. Median tumor diameter was 16 mm [range 7-40], significantly larger for cryoablation (22 mm, p = 0.002). A median of two tumors were treated per session [range 1-7]. Technical success, local control, complications, and overall survival were assessed.

RESULTS

Primary technical success was achieved for 55/60 tumors (91.7%). Median follow-up was 40.6 months (clinical) and 32.5 months (imaging, per tumor). Local control at 1, 2, and 3 years was 94.7%, 80.8%, and 76.4%, respectively, and did not differ between ablation modalities. Five of fifteen recurrent tumors underwent repeat ablation, and secondary technical success was achieved in four (80%). Assisted local tumor control at 1, 2, and 3 years was 96.2%, 89.8%, and 84.9%, respectively. Complications occurred following 24/32 sessions (75.0%) and 57.2% Common Terminology Criteria for Adverse Events (CTCAE) lower than grade 3. Of 13 pneumothoraces, 7 required chest tube placements. Hemoptysis occurred after 7/21 cryoablation sessions, and bronchopleural fistula developed more frequently with microwave (p = 0.037). Median length of hospital stay was 1 day [range 0-10], and median overall survival was 81.5 months (IQR 40.4-93.1).

CONCLUSION

Percutaneous computed tomography-guided microwave and cryoablation can treat lung metastases from ACC of the head and neck. Complications are common but manageable, with full recovery expected.

Expression profile of circular RNA and construction of circular RNA-Micro RNA network in salivary adenoid cystic carcinoma

BACKGROUND

Circular RNAs (circRNAs) is a newly discovered type of non-coding RNA, the abnormal expression of which has been demonstrated in many types of human tumors. So they have been considered as promising candidates as diagnostic and therapeutic targets in cancer. This research aimed to screen the profile of circRNA expression in salivary adenoid cystic carcinoma (SACC).

METHODS

Using the threshold of FDR < 0.05 and fold change > 2 or < 0.5, 5 up-regulated and 26 down-regulated circRNAs were identified. The reliability of sequencing was verified by the expression detection of randomly selected circRNAs via qRT-PCR.

RESULTS

Moreover, the circRNA-miRNA system was established by bioinformatics approaches and successfully identified an interaction between circRNA ABCA13 and a cancer-related miRNA (miR-138-5p), which was also verified by qRT-PCR. Moreover, the predicted molecular interaction proved that circRNA ABCA13 may promote SACC through inhibition of miR-138-5p.

CONCLUSIONS

Collectively, this study has offered the first report about the circRNA expression profile and circRNA-miRNA network in SACC. All of the above could benefit the exploration of novel therapeutic target in SACC treatment.

A pilot study for presence of circulating tumour cells in adenoid cystic carcinoma

Adenoid cystic carcinoma (ACC) is a rare salivary gland neoplasm with a poor long-term prognosis due to multiple recurrences and distant metastatic spread. Circulating tumour cells (CTCs) are tumour cells shed from a primary, recurrent, or metastatic cancer that are detectable in the blood or lymphatics. There is no literature to date confirming the presence of CTCs in ACC. The aim of this study was to determine whether CTCs are detectable in ACC. Blood samples were collected from eight patients with histologically confirmed ACC. The TNM stage of the tumour was recorded, as well as any prior treatment. CTCs were isolated by spiral microfluidics and detected by immunofluorescence staining. Three of the eight patients recruited (32.5%) had staining consistent with the presence of CTCs. Of these three patients with detectable CTCs, one had confirmed pulmonary metastasis, one had suspected pulmonary metastasis and was awaiting confirmation, and one had local recurrence confirmed on re-resection. One patient with known isolated pulmonary metastasis had previously undergone a lung metastasectomy and did not have CTCs detected. CTCs are detectable in ACC. In this small patient sample, CTCs were found to be present in those patients with recurrent local disease and known distant metastatic disease. CTCs in ACC should be investigated further for their potential use as an adjunct in staging, prognosis, and the detection of recurrence.

CASC9 plays a role in salivary adenoid cystic carcinoma in vitro by upregulation of ACLY

OBJECTIVE

The study was designed to explore the role of cancer susceptibility candidate 9 (CASC9) in salivary adenoid cystic carcinoma (SACC) (SACC-83 and SACC-LM) cell malignant phenotypes.

METHODS

Colony formation assay was used to measure cell proliferation. Transwell assay was used to detect cell migration and invasion. Flow cytometry analysis was applied to determine cell cycle distribution and apoptosis. FISH assay revealed the subcellular location of CASC9.

RESULTS

Downregulation of CASC9 inhibited SACC cell proliferation, migration, and invasion, led to cell arrest at G0/G1 phase, and facilitated cell apoptosis. In mechanism, CASC9 bound with microRNA 146b-5p (miR-146b-5p) and negatively modulated miR-146b-5p expression. MiR-146b-5p directly targeted 3' untranslated region of ATP-Citrate Lyase (ACLY) to degrade ACLY in SACC cells. CASC9 upregulated ACLY expression through competitively binding with miR-146b-5p. Furthermore, rescue assays indicated that ACLY overexpression counteracted the effects triggered by CASC9 knockdown on cell proliferation, migration, invasion, and apoptosis in SACC cells.

CONCLUSION

CASC9 facilitated the malignant phenotypes of SACC cells by the regulation of the miR-146b-5p/ACLY axis. These findings might lay foundation for SACC research.

Tumor growth rate as a prognostic factor for metastatic or recurrent adenoid cystic carcinoma of the head and neck patients treated with carboplatin plus paclitaxel

PURPOSE

Large prospective studies of chemotherapy for metastatic or recurrent adenoid cystic carcinoma (ACC) of the head and neck are lacking due to the rarity of ACC. The aim of this study is to evaluate the efficacy of carboplatin plus paclitaxel toward ACC and perform an exploratory investigation of the prognostic factors to investigate the optimal strategy for metastatic or recurrent ACC.

METHODS

We retrospectively analyzed recurrent or metastatic ACC patients treated with carboplatin plus paclitaxel between April 2007 and September 2019 in our hospital. Objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and overall survival (OS) were evaluated, and an exploratory analysis of the prognostic factors was conducted.

RESULTS

A total of 26 ACC patients were enrolled. ORR and DCR were 11.5 and 76.9%; the median PFS and OS were 8.1 and 22.3 months, respectively. From the results of the multivariate analysis, higher (≥ 6%/month) tumor growth rate (TGR) was associated with worse PFS (hazard ratio [HR] 7.00, 95% CI 1.34-36.53, p = 0.02) and OS (HR 29.33, 95% CI 3.38-254.80, p < 0.01). The median PFS (10.6 vs. 6.6 months, log-rank p < 0.05) and OS (48.5 vs. 16.9 months, log-rank p < 0.01) were significantly shorter in patients with higher TGR.

CONCLUSIONS

Carboplatin plus paclitaxel showed modest efficacy for recurrent or metastatic ACC patients. Watchful waiting may be optimal for ACC patients with lower TGR. Systemic chemotherapy should be considered when TGR increases during active surveillance.

Adenoid Cystic Carcinoma of the Larynx: A SEER Database Review

BACKGROUND

Adenoid cystic carcinoma (AdCC) of the larynx is an uncommon malignancy of the head and neck with very little literature discussing treatment paradigms and prognostic factors influencing survival.

METHODS

This retrospective cohort study uses data obtained from the Surveillance, Epidemiology and End Result database comprising of patients diagnosed with laryngeal AdCC from 1978 to 2016.

RESULTS

A total of 89 records were analyzed. High histologic grade was a significant negative prognostic factor compared to low histologic grade disease for overall survival (OS; 5-year OS: 35.7% vs 90.5%, P < .005) and disease-specific survival (DSS; 5-year DSS: 38.7% vs 95.2%, P < .005). No differences in OS (5-year OS: 88.9% vs 76.4%, P = .287) or DSS (5-year DSS: 100% vs 79.1%, P = .159) were noted between patients with early versus late American Joint Committee on Cancer (AJCC) stage disease. No differences in DSS was noted in cohorts treated with just definitive surgery versus surgery and adjuvant radiation (5-year DSS: 92.9% vs 74.3%, P = .140) even when stratified for late stage disease (5-year DSS: 100% vs 78.6%, P = .290) or high-grade histology (5-year DSS: 100% vs 83.3%, P = .773).

CONCLUSIONS

Histologic grade may be a more significant prognostic factor than AJCC stage for survival in laryngeal AdCC. Treatment with surgery and radiation may provide no additional survival advantage compared to just definitive surgery in these patients, although further study is warranted.

Establishment of PDX-derived salivary adenoid cystic carcinoma cell lines using organoid culture method

To generate a reliable preclinical model system exhibiting the molecular features of salivary adenoid cystic carcinoma (ACC) whose biology is still unclear due to the paucity of stable cell cultures. To develop new in vitro and in vivo models of ACC, the techniques of organoid culture and patient-derived tumor xenograft (PDX), which have attracted attention in other malignancies in recent years, were applied. Tumor specimens from surgically resected salivary ACC were proceeded for the preparation of PDX and organoid culture. The orthotopic transplantation of patient-derived or PDX-derived organoids was demonstrated into submandibular glands of NSG mice and those histology was evaluated. PDX-derived organoid cells were evaluated for the presence of MYB-mediated fusion genes and proceeded for in vitro drug sensitivity assay. Human ACC-derived organoids were successfully generated in three-dimensional culture and confirmed the ability of these cells to form tumors by orthotopic injection. Short-term organoid cell cultures from two individual ACC PDX tumors were also established that maintain the characteristic MYBL1 translocation and histological features of the original parent and PDX tumors. Finally, the establishment of drug sensitivity tests on these short-term cultured cells was confirmed using three different agents. This is the first to report an approach for the generation of human ACC-derived organoids as in vitro and in vivo cancer models, providing insights into understanding of the ACC biology and creating personalized therapy design for patients with ACC.

Neck involvement and disease recurrence in adenoid cystic carcinoma of the minor salivary glands: the role of surgery in primary and progressive disease

The aim of this study was to analyse the rates of metastatic events and clinical outcomes of patients with adenoid cystic carcinoma (ACC) of the minor salivary glands and to critically evaluate the role of surgical therapy. A retrospective cohort study was designed including all patients with ACC of the oral minor salivary glands treated in the study department during the years 2010-2017. Relevant clinicopathological data were analysed to determine factors with an impact on overall survival (OS) and progression-free survival (PFS). Forty-one patients with primary ACC of the oral cavity and the oropharynx were included. Cervical metastases were found in 14 patients (34.1%) and were shown to have a significant negative impact on OS (P=0.009) and PFS (P=0.03). Sixteen patients developed disease recurrence during follow-up (39.0%) and most patients exhibited local disease recurrence with or without regional or distant metastases (14/16, 87.5%). Local recurrence was treated successfully with surgery in five cases. We recommend surgical therapy for patients with ACC of the minor salivary glands, including elective neck dissection and microvascular reconstruction, to optimize the planning of adjuvant therapy.

Analysis of the clinicopathological characteristics and prognosis of adenoid cystic carcinoma of the intraoral minor salivary glands: a retrospective study of 40 cases

The clinicopathological aspects and prognostic factors of 40 patients with adenoid cystic carcinoma (ACC) of the intraoral minor salivary glands, treated between 2007 and 2017 at a single institution, were evaluated retrospectively. Twenty-six were female and 14 were male, and they ranged in age from 26 to 81 years (median 55 years). ACC occurred mainly in the palate, with 54.8% of cases presenting T3-T4 lesions. Curative surgery was performed in all patients, and 62.5% of patients were treated with postoperative adjuvant radiotherapy. In the final analysis, positive surgical margins were noted in 57.5% of cases and perineural invasion in 70%. Follow-up was at least 13 months (range 13-141 months, median 59 months). Nineteen patients (47.5%) developed recurrent disease after initial surgery and nine patients had died at the end of follow-up. The 5- and 10-year overall survival rates were 88.3% and 25.6%, respectively. The 5- and 10-year disease-free survival rates were 75.6% and 34.0%, respectively. Patients with a tumour size >4cm and those with positive surgical margins showed a significantly higher risk of local recurrence. Elective neck dissection is suggested for patients with clinically positive lymph nodes or a locally advanced tumour, especially those undergoing microvascular reconstruction. The survival analysis results are similar to those reported previously in the literature.

Targeting EGFR Enriches Stem Cell-Like Properties in Salivary Adenoid Cystic Carcinoma by Activating the Notch1 Pathway

Background

Salivary adenoid cystic carcinoma (SACC), a rare cancer arising in the salivary glands, is characterized by high rates of relapse and distant metastasis. Epidermal growth factor receptor (EGFR) has been implicated in SACC carcinogenesis. However, prospective trials of EGFR-targeting therapies in SACC are limited, and the optimum regimen is unclear.

Methods

The effects of erlotinib on cell proliferation, colony formation, ALDH enzymatic activity and tumorsphere formation were investigated in SACC cells. Expression of the cancer stem cell markers Bmi-1 and Oct4 was evaluated using Western blotting.

Results

We found that while it robustly inhibited cell growth, targeting EGFR with erlotinib enriched the ALDH⁺ cell population and elevated the clonogenicity of SACC cells, suggesting an increase in stem cell-like potential. In addition, we found that suppression of EGFR kinase activity with erlotinib led to the activation of Notch1 signaling, leading to an increase in stem cell-like properties. Moreover, the γ-secretase inhibitor GSI treatment eliminated the erlotinib-induced increase in stem cell-like properties by decreasing Notch activity.

Conclusion

Our results provide an explanation for the worsened survival observed in some studies of erlotinib therapy in SACC and provide potential therapeutic strategies by combined blockade of the EGFR and Notch1 pathways.

Management of adenoid cystic carcinoma of the head and neck: a single-institute study with over 25-year follow-up

Background

Adenoid cystic carcinoma is a rare malignant tumor arising from exocrine glands such as the major and minor salivary glands of the paranasal sinuses or the external auditory canal. Although multiple retrospective clinical studies of ACC have been reported to date, clinical questions, such as 1) long-term prognosis beyond 20 years, 2) usefulness and suitability for treatment of therapeutic interventions, 3) therapeutic goal to aim for, and 4) prognosis by recurrence sites, are still unclear.

Methods

To improve understanding and management of adenoid cystic carcinoma of the head and neck (ACC), a retrospective study with 58 new ACC cases between 1991 and 2016 was performed. The median observation period was 66.8 months (range 3–316 months). The overall clinical stages were as follows: I, 6.9%; II, 25.9%; III, 19.0%; and IV, 48.2%. Histology was cribriform/tubular type (C-T type) in 62.0% and solid type in 27.5%. The main treatment strategy was definitive surgery, which was performed in 75.2% of cases.

Results

Overall 10-year, 20-year, and 25-year survivals were 63.7, 27.3, and 20.0%, respectively. Similarly, disease-specific survival (DSSs) was 65.7, 51.2, and 38.4%, respectively, and disease-free survival was 25.2, 9.4, and 9.4%, respectively. Conducting surgery (HR: 0.19, 95% CI: 0.06–0.61, p = 0.005) and C-T type (HR: 0.32, 95% CI: 0.11–0.93, p = 0.036) were independent prognostic predictors of DSS. DSS was significantly prolonged after salvage surgery for both locoregional recurrence (p = 0.004) and lung metastatic recurrence (p = 0.012, vs best supportive care).

Conclusions

In ACC cases, both initial surgical treatment and repetitive surgical resection of resectable recurrent lesions, including both locoregional and lung metastases, resulted in longer survival. The major goal of treatment for ACC may be long-term survival including cancer-bearing survival, resulting in either natural death or intercurrent-disease death, since judging cure of ACC is almost impossible.

Trial registration

Retrospectively registered.

Unusual Presentations of Primary and Metastatic Adenoid Cystic Carcinoma Involving the Skin

Adenoid cystic carcinoma (ACC) is most commonly seen in the salivary glands but may occur at other sites. Primary or metastatic involvement of the skin is unusual. We report 2 cases of ACC with unusual presentation. In the first case, a 55-year-old woman presented with a cutaneous lesion on the right shin, and final pathology showed ACC. An extracutaneous origin was excluded by clinical and imaging studies. In the second case, a 49-year-old woman presented with a nodule on the breast, and biopsy confirmed high-grade ACC (>30% solid areas). She underwent lumpectomy and subsequent mastectomy after recurrence. Sixteen months after the initial diagnosis of ACC of the breast, distant metastases at multiple sites, including the skin, were identified. This report will increase awareness of these rare presentations of cutaneous ACC and allow correct diagnosis and appropriate management of such cases.

Adenoid cystic carcinoma of the parotid metastasising to the dura fifteen years post primary resection: A case report

Adenoid cystic carcinoma (ACC), regardless of the primary site, is typically characterized by a long clinical course associated with a high rate of distant metastases. Intracranial metastasis of ACC is a very rare entity with only few reported cases in the literature. In this study, we report an unusual case of extra-axial intracranial metastasis of ACC in the dura. The primary parotid gland tumour was resected 15 y back. No recurrence had been detected before the occurrence of extra-axial metastasis. After surgical decompression, palliative radiotherapy was administered. To our knowledge, this is the longest interval for the development of metastases following excision of a parotid adenoid cystic carcinoma. This case can raise awareness across specialties that patients with adenoid cystic carcinoma are still at risk of developing metastases even following specialist discharge.

Adenoid Cystic Carcinoma of Salivary Gland: A Ten-Year Single Institute Experience

Adenoid cystic carcinoma is a rare tumor, accounting for about 7.5% of all salivary gland neoplasms. More frequent developing in minor salivary gland, this is a slow-growing tumor with a long-lasting natural evolution, quite aggressive locally, but which has a tendency toward local recurrence and even for distant metastasis. We conducted a retrospective study limited to a period of 10 years in a single medical institution to investigate the morphoclinical profile of this tumor. Thus, we have established that about 60% of the tumors developed in men, with near 40% of the cases in patients in the sixth decade and, most common, the pathology affected the parotid and minor salivary glands from the hard palate mucosa. Histopathologically, prevailed the solid variant, with 72% cases presenting perineural invasion, and 41% cases showing positive surgical resection margins. Most cases had a long-standing asymptomatic evolution, so that at the time of diagnosis, more than two thirds of the patients were at least in stage II-pTNM, and in one-fifth of the cases histopathology showed lymph nodes disseminations.

Epigenetic alterations in salivary gland tumors

Salivary gland tumors (SGTs) comprise a heterogeneous group of benign and malignant neoplasms that exhibit significant variability in their microscopic appearance, clinical presentation, and biological behavior. The etiologic factors are unknown; however, chromosomic translocation, secondary radiation, and chemotherapy can be associated with the development of SGT. It has been indicated that epigenetic alterations can be responsible for the development and progress of these neoplasms. The epigenetic mechanisms are defined as a set of DNA changes that do not alter the sequence of nucleotide bases but alter the expression of the proteins. These alterations have been studied in the SGT, and they were associated with the development and progress of these neoplasms and may influence on SGT prognosis. Hence, we critically review the currently available data on the participation of epigenetic events on salivary gland tumors.

Utility of p63 and p40 in Distinguishing Polymorphous Adenocarcinoma and Adenoid Cystic Carcinoma

Objective:

Adenoid cystic carcinoma and polymorphous adenocarcinoma are primarily the tumor of minor salivary glands. Both show certain morphological similarities, which limit their proper diagnosis in settings where there are obscuring factors and limited biopsy material. However, there is a considerable difference in treatment and prognosis, which raises the need to distinguish these two entities. In this study, we discuss the utility of two immunohistochemical stains, p63 and p40, in different combinations for distinguishing polymorphous adenocarcinoma from adenoid cystic carcinoma.

Materials and Methods:

Two immunohistochemical stains, p63 and p40, were performed on 47 cases of adenoid cystic carcinoma and 23 cases of polymorphous adenocarcinoma.

Results:

36 out of 47 cases of adenoid cystic carcinoma showed p63+ve/p40+ve immunoprofile, followed by p63-ve/p40-ve immunoprofile, which is seen in10 cases of adenoid cystic carcinoma. However, 22 out of 23 cases of polymorphous adenocarcinoma displayed p63+ve/p40-ve immunoprofile. p63-ve/p40+ve is the least frequent observed immunoprofile, which is seen in only one case of adenoid cystic carcinoma.

Conclusion:

On combining all possible immunoprofile combinations, p63+ve/p40-ve immunoprofile appears to be the most sensitive profile for distinguishing polymorphous adenocarcinoma from adenoid cystic carcinoma.