Analysis of failure in patients with adenoid cystic carcinoma of the head and neck. An international collaborative study

Adenoid cystic carcinoma of the parotid and submandibular glands in children and young adults: A population-based study

OBJECTIVES

This study aims to analyze the behavior and treatment of adenoid cystic carcinoma (AdCC) in the pediatric and young adult population and to identify factors affecting overall survival (OS).

MATERIALS AND METHODS

The study analyzed salivary gland malignancies in patients aged 0-21 with AdCC histology using the National Cancer Database from 2004 to 2018.

RESULTS

A total of 72 patients (59.7% parotid, 36.1% submandibular, 1.4% sublingual, 2.8% unspecified) met criteria. Median age was 18 years [range: 0-21]. High-grade dysplasia was present in 67% of cases. Therapy consisted of primary surgery for all cases, regional lymph node dissection (LND) (74%), radiotherapy (71%), chemotherapy (8%), and chemoradiation (7%). The 5-year OS rate was 93.2% [95% confidence interval (CI): 86.9%-99.9%], respectively. Patients who underwent associated LND had improved OS (p = .0083, log-rank test) with a 5-year OS at 82.4% [95% CI: 66.1%-100%] versus 97.6% [95% CI: 93.0%-100%]. A significant difference in OS was found with unfavorable outcomes after positive marginal status: 5-year OS 84.1% [95% CI: 71.0%-99.7%] versus 100% [95% CI: 100%]; p < .001. Adjuvant therapy did not seem to impact the outcome.

CONCLUSION

This study confirms that AdCC in children and young adults has an overall good prognosis despite frequent high grade. It suggests that cervical LND may be of importance, but the value of systematic adjuvant therapy is not confirmed. These findings emphasize the importance and relevance of population-based studies in shaping clinical practice and informing the design of future prospective investigations.

Platinum-based adjuvant chemoradiotherapy versus adjuvant radiotherapy in patients with head and neck adenoid cystic carcinoma

PURPOSE

The objective of the study was to assess the effectiveness and toxicity of platinum-based adjuvant chemoradiotherapy (POCRT) in comparison to postoperative radiotherapy (PORT) in patients with head and neck adenoid cystic carcinoma (HNACC).

MATERIALS AND METHODS

This retrospective study analyzed patients diagnosed with HNACC at our center between January 2010 and April 2020. A 1:1 propensity score matching method was used to create a matched cohort.

RESULTS

In this study, 206 patients were analyzed, with 147 patients (71.4%) receiving postoperative radiotherapy (PORT) and 59 patients (28.6%) receiving POCRT. Twenty-one patients experienced local-regional failure. The 3-, 5-, and 10-yr local-regional control (LRC) rate for the cohort were 92.0%, 90.6%, and 86.9%, respectively. In both the entire cohort and the matched cohort, the POCRT group exhibited superior LRC compared to the PORT group (Gray's test, all P < 0.05*). Multivariate analysis identified adjuvant concurrent chemotherapy as an independent prognostic factor for LRC (Competing risks regression, HR = 0.144, 95% CI 0.026-0.802, P = 0.027*). In addition, the POCRT group had higher incidences of upper gastrointestinal toxicity and hematologic toxicities, including leukopenia, neutropenia, and anemia (all P < 0.05*).

CONCLUSION

In terms of reducing locoregional failures in HNACC patients, POCRT may potentially offer a more effective therapeutic approach than using PORT alone, although it also entails an augmented burden of treatment-related toxicity.

Adenoid cystic carcinoma of submandibular gland: Emphasis on locoregional metastasis and prognosis

OBJECTIVES

To analyze the clinicopathological features, locoregional or distant metastasis, and prognosis of adenoid cystic carcinoma of submandibular gland (SMG-AdCC).

METHODS

The clinicopathological data of 80 patients with SMG-AdCC from January 2005 to December 2017 were analyzed retrospectively, and the relationships between different parameters of SMG-AdCC and its locoregional or distant metastasis or prognosis were analyzed.

RESULTS

As of December 2019, 41 patients (51.25%) were tumor-free, while 20 patients were found to be living with tumors. The locoregional metastasis rate of grade II-III SMG-AdCC were found to be significantly higher than that of grade I. The five-year DFS and OS rates were 70.8% and 87.1%, respectively. Univariate analysis showed that clinical size, extraglandular extension, pathological grade, pathological node (pN) status, and perineural invasion were correlated with DFS. Multivariate Cox regression analysis showed that pathological grade and extraglandular extension were independent prognostic factors for DFS; pN status and extraglandular extension were independent prognostic factors impacting OS.

CONCLUSION

The pathological grade is a risk factor for locoregional metastasis of SMG-AdCC. Pathological grade, pN status, and status of extraglandular extension are independent prognostic factors for DFS/OS in SMG-AdCC patients.

Risk Factors for Locoregional Recurrence and Distant Metastasis in 143 Patients with Adenoid Cystic Carcinoma of the External Auditory Canal

AIMS

Adenoid cystic carcinoma (ACC) grows slowly and is characterised by potential recurrence and metastasis to distant organs. This study aimed to evaluate the risk factors for locoregional recurrence (LRR) and distant metastasis in patients with ACC of the external auditory canal (EAC).

MATERIALS AND METHODS

Demographic, pathological, therapeutic and survival data of 143 patients with EAC ACC were reviewed in this study. Univariate and multivariate Cox proportional hazard regression analyses were carried out to determine the risk factors for LRR and distant metastasis. Factors associated with overall survival after LRR and distant metastasis were also analysed.

RESULTS

During a median follow-up of 49 months, 31 of 143 patients were observed with LRR and 34 developed distant metastasis. Bone invasion and histological subtype were independent risk factors for locoregional recurrence-free survival. T stage and LRR were independent risk factors for distant metastasis-free survival. Salvage surgery and adjuvant radiotherapy or chemoradiotherapy for LRR resulted in better survival, whereas extrapulmonary metastasis and LRR were associated with a higher risk of poor survival after distant metastasis.

CONCLUSION

Patients with distant metastases, especially those with LRR, are at significant risk of poor prognosis. Our findings emphasise the importance of long-term regular follow-up and recommend surgical intervention with radiotherapy for recurrent EAC ACC.

The Role of Parotid Gland Invasion in Adenoid Cystic Carcinoma of the External Auditory Canal

OBJECTIVE

This study aimed to investigate the significance of parotid gland invasion in predicting distant metastasis of adenoid cystic carcinoma in the external auditory canal.

STUDY DESIGN

Single-institution retrospective cohort study.

METHODS

A retrospective review of patients with adenoid cystic carcinoma of the external auditory canal who underwent surgery was performed. Information on patient demographics, parotid gland invasion, tumor stage, perineural invasion, lymphovascular invasion, and follow-up data were collected and analyzed.

RESULTS

One hundred twenty-nine patients were identified for review. Parotid gland invasion was noted in 45 patients (34.9%). Parotid gland invasion was significantly associated with tumor stage, perineural invasion, distant metastasis, and postoperative adjuvant therapy. Distant metastasis was noted in 30 patients (23.3%). Multivariate Cox proportional hazards analysis identified parotid gland invasion as an independent risk factor for predicting distant metastasis. The 5-year distant metastasis-free survival rate was 83.6% for patients without parotid gland invasion and 61.8% for patients with parotid gland invasion (p = 0.010).

CONCLUSIONS

The parotid gland invasion rate is relatively high in adenoid cystic carcinoma of the external auditory canal and is significantly related to tumor stage. Parotid gland invasion is associated with worse distant metastasis-free survival.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:419-425, 2024.

Prognostic Significance of Histopathological Parameters for Salivary Gland Adenoid Cystic Carcinoma

Adenoid cystic carcinoma (ACC) is a rare salivary gland tumor that accounts for approximately 1% of all head and neck cancers. Despite its initial indolent behavior, long-term survival is poor due to locoregional recurrence in approximately 40% and distant metastasis in up to 60% of patients who undergo radical treatment. The histological parameters of ACC and the combination of these parameters in histopathological grading systems provide valuable prognostic information about the clinical course of the disease. Within this context, this review aims to analyze the impact of histopathological parameters, individual or combined in histopathological grading systems of malignancy, on ACC prognosis. Individual histopathological parameters such as solid pattern, presence of tumor necrosis, high-grade transformation, dominance of the epithelial component, presence of perineural and lymphovascular invasion, and positive surgical margins have negative impacts on the survival of patients with ACC. There are currently four histopathological grading systems for ACC; however, few studies have validated these systems and most of them explored small cohorts with short follow-up. Considering that the application of grading systems has been associated with ACC prognosis, a broader validation will allow not only their use for prognostic prediction but also assist in treatment planning.

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.

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.

Major and minor salivary gland cancers: A multicenter retrospective study

BACKGROUND

Most of the studies on salivary gland cancers are limited for various reasons such as being single-center, small number of patients, including only major or minor SGCs, or only including epidemiological data.

METHODS

A total of 37 medical oncology clinics from different regions of Turkey participated in this retrospective-multicenter study. The analyzed data included clinical and demographical features, primary treatment, metastasis localizations, and treatments and includes certain pathologic features.

RESULTS

The study included data from a total of 443 SGCs. 56.7% was in major salivary glands and 43.3% was in minor salivary glands. Distant metastasis in the major SGCs was statistically significantly more common than in the minor SGCs, locoregional recurrence was statistically significantly more common in the minor SGCs than in the major SGCs (p = 0.003).

CONCLUSIONS

Epidemiological information, metastasis and recurrence patterns, treatment modalities, and survival analysis of the patients over 20 years of follow-up are presented.

Survival and prognosis of metastatic head and neck adenoid cystic carcinoma

BACKGROUND

To investigate the clinical characteristics, treatment, and prognosis of patients with metastatic head and neck adenoid cystic carcinoma (HNACC).

METHOD

The clinical data of metastatic HNACC from 1999 to 2020 at the National Cancer Center of China were retrospectively collected.

RESULTS

One hundred seventy-four patients with metastatic HNACC were enrolled and median overall survival (OS) was 45.6 months. Univariate analysis indicated that smoking history, disease-free interval (DFI), number and sites of metastases, and systemic therapy were associated with OS. In the multivariate analysis, non-smokers, DFI ≥3 years, and lung metastasis were prognostic factors. Local therapy for localized disease could prolong survival in patients with both recurrent and metastatic disease.

CONCLUSION

No smoking history, DFI ≥3 years, and lung metastasis were favorable prognostic factors. Local therapy for metastases could not provide survival benefits, but local therapy for localized disease may prolong survival. Whether initial systemic therapy could improve prognosis needs further exploration.

High-grade salivary gland cancer: is surgery followed by radiotherapy an adequate treatment to reach tumor control? Results from a tertiary referral centre focussing on incidence and management of distant metastases

Purpose

Salivary Gland cancer (SGC) is a rare and heterogenous group of tumors. Standard therapeutic options achieve high local but poor distant control rates, especially in high-grade SGC. The aim of this monocentric study was to evaluate patterns of recurrence and its treatment options (local ablative vs. systemic) in a homogenously treated patient population with high-grade SGC after surgery and radio(chemo)therapy.

Methods

Monocentric, retrospective study of patients with newly diagnosed high-grade salivary gland cancer. We retrospectively reviewed clinical reports from 69 patients with high-grade salivary gland cancer in a single-center audit. Survival rates were calculated using the Kaplan–Meier method and prognostic variables were analyzed (univariate analysis: log-rank test; multivariate analysis: Cox regression analysis).

Results

The median time of follow-up was 31 months. After 5 years, the cumulative overall survival was 65.2%, cumulative incidence of local recurrence was 7.2%, whereas the cumulative incidence of distant metastases was 43.5% after 5 years. 30 of 69 patients developed distant metastases during the time of follow-up, especially patients with adenoid cystic carcinoma, salivary duct carcinoma, adenocarcinoma NOS and acinic cell carcinoma with high-grade transformation. The most common type of therapy therefore was chemotherapy (50%). 85.7% of patients with local ablative therapy of distant metastases show disease progression during follow-up afterwards.

Conclusion

With surgery and radio-chemotherapy, a high rate of loco-regional control is reached, but over 40% of patients develop distant metastases in the further follow-up which usually present a diffuse pattern involving in a diffuse metastases. Therefore, in the future, intensified interdisciplinary combination therapies even in the first-line treatment in certain subtypes of high-grade SGC should be investigated.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00405-021-07024-9.

Immunophenotypical alterations with impact on the epithelial-mesenchymal transition (EMT) process in salivary gland adenoid cystic carcinomas

Adenoid cystic carcinoma (ACC) is one of the most common malignant salivary glands neoplasms with an indolent clinical course, slow-growing but locally aggressive and quite often with delayed recurrence and distant metastasis. In order to elucidate this tumoral behavior, we conducted an immunohistochemical study investigating the alterations of epithelial phenotype with anti-cytokeratin (CK) AE1/AE3 and anti-E-cadherin antibodies, and the acquisition of mesenchymal phenotype with vimentin, fibronectin, N-cadherin and P-cadherin in salivary ACCs. Thus, we recorded a reduction of CK AE1/AE3, E-cadherin, P-cadherin and fibronectin reactivity in the solid variant and especially in the cells from the periphery of invasive neoplastic proliferations, regardless histological type. These phenotypical alterations suggest the involvement of the epithelial–mesenchymal transition (EMT) process in the progression of salivary ACCs.

Impact of tumor site on the prognosis of salivary gland neoplasms: A systematic review and meta-analysis

In numerous types of cancer, the primary tumor site can show a correlation with disease behavior and survival outcomes. In salivary gland tumors (SGTs) this association remains controversial. This study assessed the association between primary sites of SGTs and prognosis. Studies from five databases were assessed and a meta-analysis was performed using studies that presented 95 % confidence interval (95 % CI), hazard ratio (HR) and survival analysis. Gathered information from 46,361 patients showed that site had a prognostic impact on SGTs. Tumors involving minor salivary glands showed worse overall survival (HR = 1.60; 95 % CI = 1.17-2.19; p = 0.003), disease-specific survival (HR=1.63; 95 % CI = 1.12-2.37; p = 0.01), and cause-specific survival (HR=2.10; 95 % CI = 1.72-2.55; p = 0.00001). Tumors from major salivary glands showed better recurrence-free survival (HR=2.31; 95 % CI = 1.77-3.02; p = 0.00001), and locoregional control of disease (HR=2.66; 95 % CI = 1.20-5.91; p = 0.02). Our results showed that the primary site of SGTs has an impact on patient prognosis.

The immunophenotype of epithelial to mesenchymal transition inducing transcription factors in salivary gland adenoid cystic carcinomas

Adenoid cystic carcinoma (ACC) is the second most common malignant salivary glands neoplasms with a controversial biological behavior. Even though these tumors grow slowly, they have increased potential for recurrence and distant metastasis. In order to elucidate this behavior, our study aimed to investigate the immunoexpression in such tumors of the most important transcriptional factors [Twist, Snail, Slug, and zinc finger E-box binding homeobox 1 (ZEB1)] involved in the epithelial–mesenchymal transition process. The highest level of expression was recorded for Twist, present in all the investigated cases, followed by the Slug and Snail, while no tumor parenchyma reactivity was noticed for the ZEB1 factor. There were tumor reactivity differences regarding topography, histopathological variant, and nerve and lymph node invasion status. Thus, tumors developed from the intraoral minor salivary glands, with solid pattern, perineural invasion, locally aggressive and with lymph node metastasis were the most reactive. Therefore, these transcription factors could be useful as prognostic biomarkers and efficient therapeutic targets in such salivary malignancies.

Outcome of Adenoid Cystic Carcinoma of Head and Neck After Postoperative Intensity Modulation Radiotherapy: A Single Institution Study

Objective

This study was retrospectively evaluated the outcome of postoperative intensity modulation radiotherapy (IMRT) for patients with adenoid cystic carcinoma of head and neck (ACCHN), and identified the unfavorable prognostic factors.

Methods

Fifty-five ACCHN patients treated in Sichuan Cancer Hospital between January 2007 and December 2016 were retrospectively evaluated. Median age of patient was 47 years (range, 21–73 years). Thirty-five patients were male and 20 were female. In 30 patients, tumors were located in major salivary glands (54.5%), and 25 patients in minor salivary glands (45.5%). The numbers of R0, R1, and R2 surgical resection classification patients were 22 (40.0%), 20 (36.4%), and 13 (23.6%). The median total RT dose was 62 Gy (range, 46–72 Gy), and 54.5% of patients were treated with adjuvant chemotherapy. Statistical analyses were performed using the Log rank test for univariate analysis and the Cox proportional hazard model for multivariate analysis.

Results

Median follow-up period was 68.5 months (12–132 months). The 5-year local-regional recurrence-free survival (LRRFS), distant metastasis-free survival (DMFS) and overall survival (OS) were 93.9%, 75.3% and 82.5%. In univariate analysis, T stages (p=0.025) and AJCC stages (p=0.036) were the prognostic factors for OS; Age (p=0.042), T stages (p=0.025), N stages (p=0.021), AJCC stages (p=0.021) and adjuvant chemotherapy (p=0.010) were the prognostic factors for DMFS; T stage (p=0.049) was the prognostic factor for LRRFS. In multivariate factors analyses, T stages (p=0.026), AJCC stages (p=0.028) and RT dose (p=0.025) were the significant prognosticators for OS. The most common acute toxicities over three degrees were myelosuppression (5.5%), mucositis (9.1%) and dermatitis (1.8%).

Conclusion

Postoperative IMRT seems to achieve reasonable local-regional control and OS in patients with adenoid cystic carcinoma of head and neck, with acceptable treatment relative toxicities.

Liver Resection for Metastasis of Adenoid Cystic Carcinoma of the Lacrymal Gland : A Case Report and Literature Review

Adenoid cystic carcinoma (ACC) is a rare malignant tumor. The first description of the ACC dates back to 1856 by Billroth. The ACC of the lacrimal glands are very rare. They are known for their locally aggressive character. Liver metastases are almost exceptional. We report the case of a patient with hepatic metastasis ACC. After eye enucleation of the primitive lacrimal gland ACC, the patient received external adjuvant radiotherapy. Three years later, she presented an upper abdominal pain. CT scan and MRI showed a liver tumor and the diagnosis of intrahepatic cholangiocarcinoma was made regarding imaging features. A left hepatectomy was performed; histology concluded to a liver metastasis of ACC. The immediate post-operative course was uneventful and no adjuvant treatment was decided. Thirty four months later, the patient presented with lung metastasis. Liver metastasis of ACC are very rare. Extended liver surgery is recommended especially for isolated liver metastasis with a long free gap between primary tumor and the liver metastasis. Keywords: Adenoid cystic carcinoma, Hepatic metastasis, Lacrymal gland

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.

Adenoid cystic carcinoma: a review of clinical features, treatment targets and advances in improving the immune response to monoclonal antibody therapy

The natural history of adenoid cystic carcinoma (ACC) is relentless, defined by treatment failure heralded by locoregional recurrence and distant metastatic disease. In this review, we present an update of clinical features, molecular classification, current targeted therapies, immune landscapes and novel treatment targets with their respective clinical trials. The presented results are defined by a lack of overall response rate and limited progression free survival, with restriction to stable disease. In addition, ACC is resistant to immune checkpoint inhibition due to low tumour immunogenicity and lack of PD-L1 expression. Here we present a new prospective research paradigm for ACC, including the potential to target prostate specific membrane antigen (PSMA) and the potential for manipulation of target receptors in the clinic. The presentation of this review aims to promote future research to improve response rates and outcomes for therapeutics undergoing clinical trial in ACC.

Prognostic value of elective neck dissection in adenoid cystic carcinoma of head and neck: a meta-analysis. A call for randomized trials and international consensus

Adenoid cystic carcinoma of head and neck (AdCCHN) is an uncommon salivary gland cancer characterized for infrequent neck metastases, and high rate of local and distant recurrence. The aim of this meta-analysis was to analyse the significance of elective neck dissection (END) in terms of overall survival (OS) in patients with AdCCHN. A systematic literature search and meta-analysis was performed. Endpoint assessed by this meta-analysis included 5-year OS (death from any cause). Statistical heterogeneity was assessed using the Cochrane Q test and I² statistic. A pooled odds ratio (OR) was reported with 95% confidence interval (CI). There were 1934 patients in the END arm and 3083 in the observation group. The pooled OR, calculated for END vs. observation, was 0.94. Patients receiving END had similar risk for death compared to observation cohort (P=0.76). No significant difference in final outcome after patient stratification based on T stage was identified (OR for T1/T2 1.27, P=0.39; OR for T3/T4 0.95, P=0.90). Observation for cN0 neck is a reasonable option in AdCCHN. These findings suggest the need for prospective trials on indications and extent of END in AdCCHN.

Concurrent chemoradiotherapy for locally advanced unresectable adenoid cystic carcinoma of head and neck: experience from a single institute

PURPOSE

To analyze the outcome of locally advanced unresectable adenoid cystic carcinoma (ACC) of head and neck treated with radical concurrent chemoradiotherapy (CRT) at a single tertiary care centre.

METHODS

Between 2011 and 2018, 23 patients with locally advanced unresectable ACC of head and neck treated with non-surgical radical treatment with concurrent chemoradiotherapy were evaluated for outcome and toxicity. All but one patient received cisplatin-based concurrent chemotherapy and 74% of patients were treated with intensity-modulated radiotherapy.

RESULTS

Median follow-up was 53 months (range 3-115 months). Following treatment, 11 patients achieved complete response (47.8%) and of the 12 patients with residual disease, 7 patients additionally had disease stabilization without local progression. Overall 15 patients had disease progression. Median time to progression was 28 months (range 6-67 months). The 3-year and 5-year overall survival, local progression-free survival (LPFS) and distant progression-free survival (DPFS) were 78%, 79.7%, 67.4% and 63%, 50.9%, 48.6%, respectively. Acute grade 3 mucositis was observed in three patients, and one patient additionally developed grade 4 neutropenia with subsequent complete recovery. No grade 3 or higher late toxicity was observed.

CONCLUSION

Radical concurrent chemoradiotherapy is a promising treatment option in locally advanced unresectable ACC with acceptable toxicity.

Prognostic Factors and Survival in Adenoid Cystic Carcinoma of the Head and Neck: A Retrospective Clinical and Histopathological Analysis of Patients Seen at a Cancer Center

Adenoid cystic carcinoma (AdCC) is a rare malignancy that accounts for approximately 1% of all head and neck cancers. This neoplasm is characterized by slow but often relentless growth and dissemination. Our aim was to retrospectively evaluate the clinical-pathological features of patients diagnosed with head and neck AdCC and to identify possible prognostic factors. This retrospective observational study analyzed 87 cases of AdCC of the head and neck. Clinical parameters (tumor size, lymph node and distant metastasis, clinical stage, and survival) were obtained from the records. Survival curves were constructed using the Kaplan-Meier method. A p value ≤ 0.05 was considered significant. There was a slight predominance of cases diagnosed in female patients (54%). The mean age at diagnosis was 51.5 years. Analysis using Cox's proportional hazards model considering 10-year disease-specific survival identified histologic pattern and presence of perineural invasion as independent prognostic variables. Primary tumor size and distant metastasis were prognostic predictors of 5- and 10-year disease-free survival. Detailed analysis of the association between clinical-pathological parameters and prognosis can assist professionals with cancer treatment planning and adequate patient management. Considering the long-term aggressive behavior of AdCC, rigorous patient follow-up is important to identify possible locoregional or distant recurrences.

Predictors of Distant Metastasis and Survival in Adenoid Cystic Carcinoma of the External Auditory Canal

OBJECTIVE

To analyze the predictors of both distant metastasis and survival in patients with adenoid cystic carcinoma of the external auditory canal.

STUDY DESIGN

Retrospective patient review.

SETTING

A single university hospital.

PATIENTS

Eighty-two cases with adenoid cystic carcinoma of the external auditory canal were referred to our institution between 2004 and 2016.

MAIN OUTCOME MEASURES

Distant metastasis was detected by lung computed tomography, proton emission tomography computed tomography, or histopathologic examination of tissue samples. Distant metastasis predictors were analyzed using Student's t tests and χ tests. The log-rank tests of Kaplan-Meier survival curves were used to evaluate survival differences.

RESULTS

During a median follow-up of 36 months (range, 6-162 mo), distant metastasis developed in 25 patients. The occurrence of distant metastasis was significantly associated with histopathologic subtype, T classification, and local recurrence (p < 0.05). The 1-, 10-, 20-, and 25-year cumulative survival rates in the patents with DM were 95.7, 95.7, 71.7, and 0%, respectively, and all survival rates were 100% for the 57 patients without distant metastasis (p = 0.115). Median survival time after occurrence of distant metastasis was 13 months (range, 1-120 mo). Prognosis was better with solely lung metastasis than with metastases to other visceral organs or bone (p < 0.05).

CONCLUSIONS

Distant metastasis appeared to result in a poorer prognosis, occurrence of distant metastasis was significantly associated with local recurrence, extensive surgery is recommended to achieve local control and reduce distant metastasis risk. Routine follow-up investigations for detecting distant metastasis are warranted for patients with an increased risk for distant metastasis.

ICAR: endoscopic skull-base surgery

BACKGROUND

Endoscopic skull-base surgery (ESBS) is employed in the management of diverse skull-base pathologies. Paralleling the increased utilization of ESBS, the literature in this field has expanded rapidly. However, the rarity of these diseases, the inherent challenges of surgical studies, and the continued learning curve in ESBS have resulted in significant variability in the quality of the literature. To consolidate and critically appraise the available literature, experts in skull-base surgery have produced the International Consensus Statement on Endoscopic Skull-Base Surgery (ICAR:ESBS).

METHODS

Using previously described methodology, topics spanning the breadth of ESBS were identified and assigned a literature review, evidence-based review or evidence-based review with recommendations format. Subsequently, each topic was written and then reviewed by skull-base surgeons in both neurosurgery and otolaryngology. Following this iterative review process, the ICAR:ESBS document was synthesized and reviewed by all authors for consensus.

RESULTS

The ICAR:ESBS document addresses the role of ESBS in primary cerebrospinal fluid (CSF) rhinorrhea, intradural tumors, benign skull-base and orbital pathology, sinonasal malignancies, and clival lesions. Additionally, specific challenges in ESBS including endoscopic reconstruction and complication management were evaluated.

CONCLUSION

A critical review of the literature in ESBS demonstrates at least the equivalency of ESBS with alternative approaches in pathologies such as CSF rhinorrhea and pituitary adenoma as well as improved reconstructive techniques in reducing CSF leaks. Evidence-based recommendations are limited in other pathologies and these significant knowledge gaps call upon the skull-base community to embrace these opportunities and collaboratively address these shortcomings.

Major and minor salivary gland tumours

Salivary glands carcinomas are very rare epithelial malignant tumors. In 2013 in Europe, 7800 new diagnoses were estimated, 8.5 % of all head and neck cancer. The last WHO classification (2017) counts more than 20 malignant histotypes, this variety as well as the rarity of some of them needs a skilled pathologist for diagnosis. Surgery remains the mainstay of management followed by radiation in high-grade and high-risk pathological features cases. The intensity modulated radiotherapy (IMRT) should be preferred over conformational radiotherapy techniques as adjuvant and exclusive treatment in advanced cases. Particle radiotherapy (i.e. protons, carbon ions) can have a role in advanced/unresectable disease since it was proved to have better results over photons in loco-regional control both in adenoid cystic carcinoma and in other histotypes. Although chemotherapy is still the most frequent treatment for metastatic patients, several new compounds (i.e. anti-angiogenic agents, tailored agents, checkpoint inhibitors) are under investigation.

[Diagnosis, prognosis and treatment of sinonasal carcinomas (excluding melanomas, sarcomas and lymphomas)]

Sinonasal carcinomas account for 3% of ENT cancers. They are subdivided into squamous cell carcinomas (50%), adenocarcinomas [20%, mostly of intestinal type (ITAC)], and more rarely, adenoid cystic carcinomas, olfactory neuroblastomas (=esthesioneuroblastomas), neuroendocrine carcinomas or undifferentiated sinonasal carcinomas (SNUC). The 5-year survival rates are, in descending order, 72% for neuroblastomas, 63% for adenocarcinomas, 50-60% for large-cell neuroendocrine carcinomas, 53% for squamous cell carcinomas, 25-50% for adenoid cystic, 35% for small-cell neuroendocrine carcinomas and 35% for SNUC and newly discovered histologies. Surgery is the main treatment; endoscopic approaches reduce the morbidity with equivalent tumour control. Intensity-modulated radiation therapy (IMRT) is almost systematic. Nodal involvement is rare in ethmoidal adenocarcinomas and adenoid cystic carcinomas; it is intermediate and may justify prophylactic radiotherapy for N0 necks in SNUC, neuroblastoma, squamous cell carcinomas and sinonasal neuroendocrine carcinomas. IMRT or proton therapy is the mainstay of treatment of unresectable disease. Radiotherapy optimization by carbon ion therapy for adenoid cystic carcinomas, or by chemotherapy for all carcinomas with IMRT or proton therapy, is investigated within clinical trials in France. Neoadjuvant chemotherapy is reserved for rapidly progressive disease or histologies with a high metastatic potential such as neuroendocrine carcinomas or SNUC. Given their histologic and molecular specificities and different relapse patterns, an expertise of the REFCOR network, with REFCORpath review, is likely to correct diagnoses, rectify treatments, with an impact on survival.

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.

A prospective multicentre REFCOR study of 470 cases of head and neck Adenoid cystic carcinoma: epidemiology and prognostic factors

BACKGROUND

Adenoid cystic carcinoma (ACC) accounts for 1% of malignant head and neck tumours [1] and 10% of salivary glands malignant tumours. The main objective of our study is to investigate the prognostic factors influencing the event-free survival (EFS) of patients with ACC.

PATIENTS AND METHODS

A multicentre prospective study was conducted from 2009 to 2018. All 470 patients with ACC whose survival data appear in the REFCOR database were included in the study. The main judgement criterion was EFS. Both a bivariate survival analysis using log-rank test and a multivariate using Cox model were performed using the R software.

RESULTS

Average age was 55 years. Females accounted for 59.4% of the cohort. The body mass index (BMI) was normal in 86% of cases. Tumours were located in minor salivary glands in 60% of cases. T3/T4 stages represented 58%; 89% of patients were cN0. histological grade III was observed on 21% of patients. The EFS and overall 5-year survival rates were 50% and 85%, respectively. After adjustment, the most significant pejorative prognostic factors were age ≥65 years (hazard ratio [HR] = 1.67), BMI<16.5 (HR = 2.62), and lymph node invasion cN (HR = 2.08).

CONCLUSION

Age, BMI and N stage are the three main clinical prognostic factors determining EFS identified in this prospective series of patients with ACC. Such findings open new research perspectives on the influence of these components on initial patient care.

Distant metastasis of salivary gland cancer: Incidence, management, and outcomes

BACKGROUND

Distant metastases (DMs) are the primary cause of treatment failure in patients with salivary gland carcinoma. There is no consensus on the standard treatment.

METHODS

Patients with DMs were identified from an institutional database of 884 patients with salivary gland cancer who underwent resection of the primary tumor between 1985 and 2015. Survival outcomes for patients with DMs were determined with the Kaplan-Meier method. Univariate and multivariate analyses were performed to identify factors associated with DM.

RESULTS

Of the 884 patients identified, 137 (15%) developed DMs during follow-up. Most of the primary tumors (n = 77 [56%]) were located in a major salivary gland. At clinical presentation, 53% of the tumors were classified as T3 or T4, and 32% had clinical node metastases. The median time to DM was 20.3 months. The factors associated with shorter distant recurrence-free survival were male sex, high-risk tumor histology, and advanced pathological T and N classifications. Patients with bone metastases had a lower survival rate than patients with lung metastases. The total number of DMs in a patient was inversely associated with survival. Patients who underwent surgical resection of DMs had a significantly higher 5-year rate of metastatic disease-specific survival than patients who underwent observation or nonsurgical treatment (44%, 29%, and 19%, respectively; P = .003).

CONCLUSIONS

In patients with DMs of salivary gland carcinoma, survival is negatively associated with high-grade histology, bone DMs, and the total number of DMs. Metastasectomy can help to lengthen disease-free survival.

Primary Adenoid Cystic Carcinoma of the Upper Anterior Mediastinum Mimicking a Thyroid Tumor: A Case Report and Review of Literature

Primary adenoid cystic carcinoma (ACC) of the upper anterior mediastinum mimicking a thyroid tumor has rarely been seen in clinical practice and lacks a standard of care therapy. Here, we report a 47-year old female patient with an ACC originated from the upper anterior mediastinum presenting as a thyroid gland tumor. The patient received gross surgical resection of the tumor and underwent post-surgical chemotherapy and radiotherapy. The patient was free from local recurrence 3-years following initial treatment, but developed multiple lung metastases. She remains under clinical observation without discomfort and is still followed as an outpatient. Here, we also summarized recent reports of similar cases with hope to provide some experience for future clinical practice.

NT-3/TrkC Axis Contributes to the Perineural Invasion and the Poor Prognosis in Human Salivary Adenoid Cystic Carcinoma

The present study was aimed to investigate the role and mechanism of neurotrophin-3 (NT-3) and its specific receptor tropomyosin receptor kinase C (TrkC) in the perineural invasion (PNI) process of the salivary adenoid cystic carcinoma (SACC). The co-cultured system between SACC cells and Schwann cells (SCs) was employed to detect the expression of NT-3 and TrkC. The results of ELISA, qRT-PCR and western blot showed that NT-3 was noticeably elevated in the co-cultured SACC-83 cells, while TrkC was increased in the co-cultured SCs. The results of scratch wound healing, migration, and 3D co-culture assays showed that the directional migration abilities of the co-cultured SACC-83 cells and SCs were significantly increased. Under the stimulation of NT-3, the directional motor ability of SACC-83 cells and SCs was significantly improved, and the apoptosis of SACC-83 cells and SCs were obviously inhibited. In addition, blocking TrkC by its specific inhibitor AZD7451 could significantly inhibit these effects. Immunohistochemistry staining showed that the positive expression of NT-3 (88.5%) and TrkC (92.3%) was significantly correlated with the PNI in SACC specimens (P < 0.05). Additionally, the high expression of NT-3 was significantly associated with the poor prognosis of SACC patients (P < 0.05). The present study indicated that NT-3/TrkC axis contributed to the PNI progression and the poor prognosis of SACC via regulating the interaction between SACC cells and SCs. Interruption of the interaction between SACC cells and SCs by blocking the NT-3/TrkC axis might be an effective strategy for anti-PNI therapy in SACC.

[Treatment plan and prognosis of salivary adenoid cystic carcinoma with lung metastasis]

Salivary adenoid cystic carcinoma (SACC) is a common malignant tumor in the oral and maxillofacial region and accounts for approximately 3%-5% of all head and neck carcinomas. SACC always occurs in the palatal salivary gland and parotid gland. The tumor has the characteristics of strong invasion, perineural invasion, high hematogenous metastasis, and low lymph node metastasis rate. The biological characteristics of SACC determine the specificity of clinical treatment. Thus far, few clinical trials have investigated the efficacy of systemic therapy owing to the rarity of SACC with lung metastasis. Moreover, long-term results are poor, and no consensus on standard treatment has been reached yet. This systematic review aims to provide a retrospective analysis of treatment options and prognosis for SACC with lung metastasis and evidence for future clinical treatment.

MYB Translocation Status in Salivary Gland Epithelial-Myoepithelial Carcinoma: Evaluation of Classic, Variant, and Hybrid Forms

Epithelial-myoepithelial carcinoma (EMC) is a malignant salivary gland neoplasm comprised of a biphasic arrangement of inner luminal ductal cells and outer myoepithelial cells. Adenoid cystic carcinoma (AdCC) is also a biphasic tumor comprised of ductal and myoepithelial cells, but these components tend to be arranged in a more cribriform pattern. The occurrence of "hybrid carcinomas" that show mixed patterns of EMC and AdCC raises questions about the relationship of these morphologically overlapping but clinically distinct tumors. AdCCs frequently harbor MYB-NFIB gene fusions. Mapping of EMCs (including hybrid forms with an AdCC component) for this fusion could help clarify the true nature of EMC as a distinct entity or simply as some variant form of AdCC. Twenty-nine cases of EMC were evaluated including 15 classic low-grade EMCs, 7 intermediate-grade EMCs, 2 EMCs with myoepithelial anaplasia, 1 EMC with high-grade transformation, and 4 hybrid EMCs with an AdCC component. Break apart fluorescence in situ hybridization for MYB was performed, as was MYB immunohistochemistry. For the hybrid carcinomas and those with high-grade transformation, the divergent tumor components were separately analyzed. A MYB translocation was identified in 5 of 28 (18%) tumors including 3 of 4 (75%) hybrid carcinomas and 2 of 7 (29%) intermediate-grade EMCs. For the positive hybrid carcinomas, the fusion was detected in both the EMC and AdCC components. The MYB fusion was not detected in any of the classic EMCs (0/15) or in any of the EMCs with myoepithelial anaplasia (0/2) or high-grade transformation (0/1). The fluorescence in situ hybridization assay was unsuccessful in 1 case. MYB immunostaining was seen in 5 of 5 fusion-positive cases, and also 9 of 23 fusion-negative tumors. Classic low-grade EMCs are genetically distinct from AdCCs in that they do not harbor MYB fusions. The presence of a MYB fusion in EMCs showing hybrid features of AdCC or exhibiting highly infiltrative growth points to a subset of these tumors that may well be true AdCCs masquerading as EMCs.

Prognostic factors and survival in adenoid cystic carcinoma of the sinonasal cavity

BACKGROUND

Optimal treatment and prognostic factors affecting long-term survival in patients with sinonasal adenoid cystic carcinoma (ACC) have yet to be clearly defined.

METHODS

We conducted a retrospective review of patients treated with curative intent from 1980-2015 at MD Anderson Cancer Center.

RESULTS

One hundred sixty patients met inclusion criteria, including 8 who were treated with radiotherapy alone. Median follow-up time was 55 months. The 5-year overall survival (OS) and disease-free survival (DFS) rates were 67.0% and 49.0%, respectively. The 10-year OS and DFS rates were 44.8% and 25.4%, respectively. Factors that portended for poor survival on multivariate analysis were recurrent disease, any solid type histology, epicenter in the sinus cavity, the presence of facial symptoms, or the original disease not treated with surgery. There was no association between surgical margin status or nodal status and survival.

CONCLUSION

In this large cohort of patients with sinonasal ACC with extended follow-up, long-term survival is better than reported in prior literature. Future research should target patients with adverse risk factors.

CXCR4 and PD-1 Expression in Head and Neck Cancer with Perineural Spread

Background  Perineural spread (PNS) is a marker of aggressiveness and has been shown to occur in cranial nerves due to advanced mucosal and cutaneous head and neck cancer. Receptors CXC chemokine receptor 4 (CXCR4) and programmed cell death-1 (PD-1) have been shown to be overexpressed in a variety of cancers with PNS, with the inhibition of these pathways offering a potential future treatment. Methods  Retrospective immunohistochemical staining for the CXCR4 and PD-1 receptors was performed on 28 head and neck specimens that demonstrated PNS from January 2017 to August 2017, at Royal Brisbane and Women's Hospital, Brisbane, Australia. Results  CXCR4 staining was positive in 52 and 60% of the squamous cell carcinoma (SCC) and adenoid cystic carcinoma PNS specimens, respectively. Cutaneous SCC tumors with no PNS stained positively in 33%. No significant staining for PD-1 in peritumoral lymphocytes or tumor specimens was seen. Conclusion  CXCR4 is overexpressed in advanced skin cancer and head and neck tumors that demonstrated PNS to large cranial nerves. Overall, these results provide strong support for using CXCR4 as a biomarker and further investigation of immunotherapeutic agents that could inhibit tumor progression via targeting CXCR4 expression.

Adenoid cystic carcinoma evaluation and management: progress with optimism!

PURPOSE OF REVIEW

Adenoid cystic carcinoma (ACC) when diagnosed presents several diagnostic and treatment challenges. The standard treatment of surgery and postoperative radiotherapy has remained the standard of care for the past 3 decades. The purpose of this review is to update what's been reported and what's new since the last review in 2004.

RECENT FINDINGS

As accurate a histological diagnosis and staging of disease should be achieved prior to commencing any treatment. Patients' prognosis, in the long term, is determined by the finding of any solid tumour component in the examined excised specimen. The continued treatment of patients with ACC by surgery and postoperative radiotherapy has not changed in the long-term tumour-free outcome of patients. The majority of patients die because of loco-regional failure and/or distant metastases. Optimism is being generated by the findings at the molecular and genetic level of ACC giving hope that nonsurgical treatment can be complemented by novel treatments that will improve patients' disease cure and improved long-term survival.

SUMMARY

The histological grading determined by optical methods has not advanced our selection of treatment and new recent research findings on molecular and genetic factors give new hopes to changing the ACC classification, determining differing treatments and thus influencing an improved and prolonged tumour-free survival for more patients.

Defining the surgical margins of adenoid cystic carcinoma and their impact on outcome: An international collaborative study

BACKGROUND

The mainstay of treatment in adenoid cystic carcinoma (ACC) of the head and neck is surgical resection with negative margins. The purpose of this study was to define the margin status that associates with survival outcomes of ACC of the head and neck.

METHODS

We conducted univariate and multivariate analyses of international data.

RESULTS

Data of 507 patients with ACC of the head and neck were analyzed; negative margins defined as ≥5 mm were detected in 253 patients (50%). On multivariate analysis, the hazard ratios (HRs) of positive margin status were 2.68 (95% confidence interval [CI], 1.2-6.2; p = .04) and 2.63 (95% CI, 1.1-6.3; p = .03) for overall survival (OS) and disease-specific survival (DSS), respectively. Close margins had no significant impact on outcome, with HRs of 1.1 (95% CI, 0.4-3.0; p = .12) and 1.07 (95% CI, 0.3-3.4; p = .23) for OS and DSS, respectively, relative with negative margins.

CONCLUSION

In head and neck ACC, positive margins are associated with the worst outcome. Negative or close margins are associated with improved outcome, regardless of the distance from the tumor. © 2017 Wiley Periodicals, Inc. Head Neck 39: 1008-1014, 2017.

Elevated TARP promotes proliferation and metastasis of salivary adenoid cystic carcinoma

OBJECTIVE

This study aims to analyze the expression of T-cell receptor γ chain alternate reading frame protein (TARP) in salivary adenoid cystic carcinoma (SACC) and its distant metastases and to investigate its influences on the development and progression of SACC.

STUDY DESIGN

TARP expression was analyzed in 50 primary SACCs, 13 specimens of metastatic adenoid cystic carcinoma of salivary gland origin, and 20 noncancerous tissues around SACC via immunohistochemistry. Cell Counting Kit-8 tests, wound healing assay, and Transwell experiments were performed to evaluate the effects of lentivirus-mediated TARP overexpression on the proliferation, migration, and invasion of SACC cells.

RESULTS

TARP expression was significantly increased in primary SACCs compared with adjacent noncancerous tissues, and this increase was further enhanced in metastases compared with primary SACCs. The expression level of TARP correlated significantly with tumor size, tumor-node-metastasis stage, perineural invasion, histologic type, and distant metastasis. Furthermore, TARP overexpression promoted the growth, migration, and invasion of SACC cells.

CONCLUSIONS

TARP plays an important role in and may be used as a marker to indicate the development and progression of SACC.

Clinical outcomes of adenoid cystic carcinoma of the head and neck: a single institution 20-year experience

Background:

This study reports the clinical outcomes of head and neck adenoid cystic carcinoma treatment over a 20-year period.

Methods:

The treatment outcome of 51 head and neck adenoid cystic carcinoma patients treated between 1992 and 2013 were analysed. Patients were stratified into radical treatment and disease control groups.

Results:

A total of 40 patients underwent surgery and post-operative radiotherapy. The 10-year disease-specific survival rate was 93 per cent. Eleven patients had tumour recurrence: of these, nine were pulmonary metastases. The 11 patients in the disease control group had a median follow up of 21 months (range, 2–172 months); 5 underwent radical radiotherapy with palliative intent.

Conclusion:

There was late tumour recurrence in over 25 per cent of patients. Adenoid cystic carcinoma has a high tendency to relapse even after radical excision and adjuvant therapy. However, definitive radiotherapy should still be considered on an individual basis because it may provide local control and prolong patient survival.

Cervical lymph node metastasis in adenoid cystic carcinoma of oral cavity and oropharynx: A collective international review

The purpose of this study was to suggest general guidelines in the management of the N0 neck of oral cavity and oropharyngeal adenoid cystic carcinoma (AdCC) in order to improve the survival of these patients and/or reduce the risk of neck recurrences. The incidence of cervical node metastasis at diagnosis of head and neck AdCC is variable, and ranges between 3% and 16%. Metastasis to the cervical lymph nodes of intraoral and oropharyngeal AdCC varies from 2% to 43%, with the lower rates pertaining to palatal AdCC and the higher rates to base of the tongue. Neck node recurrence may happen after treatment in 0-14% of AdCC, is highly dependent on the extent of the treatment and is very rare in patients who have been treated with therapeutic or elective neck dissections, or elective neck irradiation. Lymph node involvement with or without extracapsular extension in AdCC has been shown in most reports to be independently associated with decreased overall and cause-specific survival, probably because lymph node involvement is a risk factor for subsequent distant metastasis. The overall rate of occult neck metastasis in patients with head and neck AdCC ranges from 15% to 44%, but occult neck metastasis from oral cavity and/or oropharynx seems to occur more frequently than from other locations, such as the sinonasal tract and major salivary glands. Nevertheless, the benefit of elective neck dissection (END) in AdCC is not comparable to that of squamous cell carcinoma, because the main cause of failure is not related to neck or local recurrence, but rather, to distant failure. Therefore, END should be considered in patients with a cN0 neck with AdCC in some high risk oral and oropharyngeal locations when postoperative RT is not planned, or the rare AdCC-high grade transformation.

Definitive proton radiation therapy and concurrent cisplatin for unresectable head and neck adenoid cystic carcinoma: A series of 9 cases and a critical review of the literature

BACKGROUND

The primary treatment for head and neck adenoid cystic carcinoma (ACC) is surgery. Infrequently, however, ACC's propensity for perineural and base of skull invasion can preclude definitive surgical management. We present our experience with proton radiation therapy (RT) and concurrent platinum-based chemotherapy.

METHODS

Nine patients with unresectable node-negative, nonmetastatic head and neck ACC received definitive proton RT and concurrent cisplatin. Outcomes and toxicities were recorded. A systematic review of the literature was performed.

RESULTS

Median follow-up was 27 months (range, 9.2-48.3 months). Four patients achieved complete response at the primary site, and an additional 4 patients achieved stabilization of local disease. Only 1 patient developed local disease progression. Four patients had 5 acute grade 3 (G3) toxicities, and 1 patient developed a chronic G4 optic nerve disorder.

CONCLUSION

Our preliminary results suggest proton RT and concurrent chemotherapy is a definitive treatment option for select patients with head and neck ACC. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1472-E1480, 2016.

Ongoing challenges in the treatment of adenoid cystic carcinoma of the head and neck

BACKGROUND

Adenoid cystic carcinoma is a malignant tumour of major and minor salivary glands. Distant metastasis and poor survival are persistent in the literature, with recent publications aimed at understanding molecular pathogenesis and development of pharmaceutical therapeutic options.

AIM

Provide an update of recent studies in the management of adenoid cystic carcinoma of the head and neck.

METHODS

Literature search using Medline, Scopus, Google Scholar, the Cochrane Database of Systematic Reviews and the Cochrane central register of controlled trials for articles on adenoid cystic carcinoma from January 2005 to January 2015.

CONCLUSION

Adenoid cystic carcinoma is characterized by a slow growing mass, with distant metastasis independent of local or regional control. Primary tumour resection remains the preferred option with radiotherapy having an adjuvant role. Recent advances have been made with novel targeted therapies however, limited to clinical trials and advanced disease.

Pattern of recurrent disease in major salivary gland adenocystic carcinoma

This study aims to evaluate the long-term outcome of major salivary gland adenocystic carcinoma (ACC). This is a retrospective review of 54 cases of ACC during a 35-year period from 1974 to 2009 at the Helsinki University Central Hospital, Helsinki, Finland. Medical records and histological samples were reviewed. All patients had a minimum follow-up time of 5 years or until death. Most of the tumours occurred in the parotid gland (n = 30, 56%) followed by submandibular gland (n = 22, 41%) and sublingual gland (n = 2, 4%). Fifty-two patients (96%) were treated with curative intent. All of these patients except one were primarily treated with surgery, and 29 patients (54%) also received postoperative radiotherapy for their primary tumour. Two patients (4%) received palliative radiotherapy. For those treated with curative intent, 32 patients (62%) had disease recurrence. Twenty-four patients (75%) had their first disease recurrence within 5 years and eight patients (25%) later than 5 years. The difference in the length of recurrence-free time interval (<5 vs. >5 years) had a significant impact on 5-year overall survival (OS) and disease-specific survival (DSS). The OS, DSS and disease-free survival (DFS) across stages I-IV varied between 46-100, 50-100 and 46-100%, respectively. Age over 45 years, T stage, and presence of neck metastases had a significant negative prognostic effect. More than half of the patients had recurrent disease. An extended follow-up for these patients seems feasible as most of the distant metastases were detected within a 10-year period.