Tracheobronchial Adenoid Cystic Carcinoma Treated Successfully With Chemoradiotherapy Followed by Durvalumab: A Case Report.

BACKGROUND/AIM: Tracheobronchial adenoid cystic carcinoma (ACC) is a rare type of malignancy. Although complete resection is standard treatment for localized ACC, treatment for unresectable ACC has not been established. It is unclear whether concurrent chemoradiotherapy (CCRT) followed by immune checkpoint inhibitor (ICI) therapy is effective for ACC. CASE REPORT: A 49-year-old man was admitted to our hospital for the treatment of dyspnea and thickening of the bronchial wall from the tracheal carina to the left main bronchus, as observed on a CT scan. Systemic examinations and transbronchial biopsy led to a diagnosis of locally advanced ACC. Although radiotherapy and chemotherapy are not regarded as very sensitive for ACC, a favorable response was obtained with CCRT. Following CCRT, he received ICI therapy with durvalumab for 1 year. The patient has remained in a stable condition 18 months after therapy, with no recurrence. CONCLUSION: ICI after CCRT might be a promising treatment option for unresectable tracheobronchial ACC.

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.

A population study comparing tracheal and lung adenoid cystic carcinoma.

BACKGROUND: Thoracic adenoid cystic carcinoma (ACC) is rare, and the differences between tracheal and lung lesions have not been fully understood. METHODS: Patients were identified from a Chinese cancer center (FUSCC) (2005-2022) and the Surveillance, Epidemiology, and End Results (SEER) database (2000-2019). Incidence was calculated and trends were quantified. Clinicopathological features and overall survival (OS) were analyzed. Nomograms predicting OS were constructed. RESULTS: Totally, 55 tracheal adenoid cystic carcinoma (TACC) and 25 lung and bronchus adenoid cystic carcinoma (LACC) were included in a Chinese cohort, 121 TACC and 162 LACC included in the SEER cohort. There were larger tumor sizes, more lymph nodes and distant metastases for LACC than TACC patients. TACC patients are more likely to get local treatments. Patients with LACC had significantly worse median OS than patients with TACC (SEER cohort: 68.0 months vs. 109.0 months, p = 0.001, Chinese cohort: 62.9 months vs. 124.8 months, p = 0.061). Age, lymph node metastasis, distant metastasis and local treatment were identified as independent prognostic factors for OS of TACC. Distant metastasis and local treatment were identified for LACC. Specifically, surgery alone or in combination with radiotherapy is crucial for improving survival in both TACC and LACC. Only TACC benefits from radiotherapy alone, while chemotherapy does not improve survival for either. The nomograms constructed using these factors revealed good prognostic accuracy. CONCLUSIONS: LACC is more aggressive and has a worse prognosis than TACC. TACC patients have more opportunities for local treatment, which is important for the prognosis of both TACC and LACC. Nomograms were created for TACC and LACC to aid in personalized survival predictions and clinical decisions.

Prognosis of primary breast salivary gland-type carcinoma: a propensity score-matching analysis with invasive carcinoma of no special type based on the SEER database for years 2010-2020.

BACKGROUND: Primary breast salivary gland-type carcinoma has weak evidence to support its management due to its rare occurrence and limited data regarding its clinicopathological features and prognosis. Therefore, this study aimed to assess clinicopathological features and prognosis for this type of carcinoma diagnosed over the past decade and compared those to the common breast invasive carcinoma of no special type (NST). METHODS: This study used the Surveillance, Epidemiology, and End Results (SEER) database to extract data regarding primary breast salivary gland-type carcinoma. Using a propensity score-matching approach, the prognosis was compared with invasive carcinoma, NST. RESULTS: This study included 488 cases of salivary gland-type carcinoma and 375,660 cases of invasive carcinoma, NST, giving an occurrence ratio of 1 to 770. Adenoid cystic carcinoma (81%) formed the majority of salivary gland-type carcinoma, followed by secretory carcinoma (13%). For salivary gland-type carcinoma, acinic cell carcinoma histological type, tumor grade 3, HER2-overexpressed status, and higher AJCC stage groups were significant worse prognostic factors for breast cancer-specific survival in univariate analyses (p < 0.05). Nonetheless, tumor grade 3 and higher AJCC stage groups remained as significant independent prognostic factors in multivariate analysis (p < 0.05). The apparent better breast cancer-specific survival of salivary gland-type carcinoma as compared to that of invasive carcinoma, NST, was diminished following adjustment for differences in baseline clinicopathological features and treatment-related variables. CONCLUSIONS: This study suggests that when managing primary breast salivary gland-type carcinoma, greater emphasis should be given to the tumor grade and AJCC stage group in addition to acinic cell carcinoma histological type and HER2 overexpression. Conventional prognostic factors are important as salivary gland-type carcinoma had similar prognosis as invasive carcinoma, NST, following adjustment for confounding variables.

[Diagnosis and treatment of subglottic mass（report of 5 cases）].

Subglottic masses is very rare. The clinical data of five cases of subglottic mass in our hospital from 2017 to 2022 were summarized, and their clinical manifestations, auxiliary examination findings, treatment plan and pathological features were analyzed. Among the 5 patients, 1 case was subglottic pleomorphic adenoma, 1 case was subglottic granuloma, 1 case was subglottic breast cancer metastasis, 1 case was subglottic primary adenoid cystic carcinoma, and 1 case was immunoglobulin G4-related disease. No recurrence was observed in the patients so far. Subglottic mass is easy to be missed. Therefore, when the lesion is suspected in this area, the examination of ear, nose and throat should be carried out systematically to detect the lesion early and improve the prognosis.

Adenoid Cystic Carcinoma, Clinical Presentation, Current Treatment and Approaches Towards Novel Therapies.

Adenoid cystic carcinoma (AdCC) is a rare cancer originating from secretory glands with unknown aetiology. It is one of the most dominant malignant salivary tumours (MST). However, it can arise in other areas of the head and neck region and in secretory glands outside this area. It occurs at all ages, but is more frequent between 50-70 years of age and more common in females than in males. The symptoms of AdCC are generally unspecific and the clinical diagnosis of AdCC maybe challenging, partially due to its heterogenous histopathology and indolent growth. Moreover, there is a lack of good prognostic markers, and due to its rarity, it is difficult to predict which therapeutic methods are the most optimal for each patient, especially since very late recurrences occur. This review presents some major characteristics of AdCC and some current treatments for this disease.

Salivary gland adenoid cystic carcinoma in the U.S population: Importance of grade, site of metastases, and adjuvant radiation for survival.

BACKGROUND: Adenoid cystic carcinoma (AdCC) is a rare and relatively heterogenous salivary gland malignancy, for which there is debate regarding grading, and clinical prognostic factors, including the role of adjuvant radiotherapy. METHODS: Surveillance, Epidemiology, and End Results (SEER) data were reviewed for AdCC cases from 2000 to 2018. RESULTS: A total of 1978 patients with AdCC were identified. Most patients were between 50 and 59 years of age (21.4 %), female (59.9 %), and Caucasian (76.8 %). Most tumors were localized at presentation (44.3 %), and moderately differentiated (or grade II) (43.7 %). Overall and DSS 5-year survival rates were 70.7 % (95 % CI, 69.9-78.8), and 78.6 % (95 % CI, 77.6-79.6). The best overall 5-year survival rate was observed for those treated with surgery plus radiation, 76.8 % (95 % CI, 75.5-78.1). Multivariate analysis revealed male sex, age > 65 (H.R. 2.659 (95 % CI,2.291-3.098), p < .001), grade III/IV (H.R.5.172 (95 % CI, 3.418-7.824), p < .001), nodal metastasis, distant metastasis (H.R. 2.400 (95 % CI, 2.178-2.645), p < .001), chemotherapy only, and combination therapy as negative prognostic factors, and receiving surgery plus radiation therapy (H.R.0.586 (95 % CI, 0.505-0.679), p < .001) as a positive prognostic factor. When limited just to the lungs, had much better survival than those patients with distant metastases to other sites such as the bones and liver (p < .001). CONCLUSION: This SEER study identifies grade, particularly III and IV, to be the strongest single predictor of worse survival. Patients did best when treated with surgery and postoperative radiotherapy. These results can inform future management of patients with this challenging cancer type.

Salivary gland-type cancers: cross-organ demographics of a rare cancer.

BACKGROUND: Salivary gland-type cancers (SGTCs) are histologically heterogeneous and can affect organs other than the salivary glands. Some tumors outside the salivary glands are diagnosed on their unique histological characteristics. Comprehensive cross-organ studies on SGTCs are limited. METHODS: We retrospectively analyzed the data of patients with salivary duct carcinoma (SDC), adenoid cystic carcinoma (AdCC), mucoepidermoid carcinoma (MEC), epithelial-myoepithelial carcinoma (EMC), acinic cell carcinoma (AcCC), and polymorphous adenocarcinoma (PAC) who visited our institution between 2009 and 2019. The primary tumor sites were classified into four categories; major salivary glands, head/neck (H/N) excluding (exc) major salivary glands (MSG) regions, broncho-pulmonary regions, and "others". H/N exc MSG was further divided into three subcategories, nasal/paranasal sinus, oral and pharynx/larynx. RESULTS: We identified 173 patients with SGTCs, with SDC, AdCC, MEC, EMC, AcCC, and PAC accounting for 20%, 42%, 27%, 3%, 8%, and 1% of the cases, respectively. The most frequent primary site was the major salivary glands (64%), followed by H/N exc MSG regions (27%), broncho-pulmonary regions, and "others", thus non-salivary gland origins accounted for 9% of all cases. Patients with SDC, MEC, AcCC, or SGTC of the major salivary glands and broncho-pulmonary regions were more frequently treated by surgery. The overall survival time of the patients with MEC was significantly better than that of patients with SDC or EMC. CONCLUSIONS: This cross-organ study highlights the clinical significance of SGTCs, underscoring the need for developing novel therapies for this rare disease entity.

Molecular Profiling and the Impact of Treatment on Outcomes in Adenoid Cystic Carcinoma Type I and II.

PURPOSE: Adenoid cystic carcinoma (ACC) is an uncommon salivary gland cancer with no approved therapies available to treat advanced, incurable disease. Recent molecular profiling efforts have identified two important subtypes: the more aggressive ACC-I is characterized by Notch pathway alterations and MYC amplification whereas ACC-II demonstrates a more indolent phenotype and TP63 overexpression. EXPERIMENTAL DESIGN: This retrospective observational cohort study involved de-identified samples from 438 patients with ACC with tumor samples sent for commercially-available molecular profiling (Caris Life Sciences). Next-generation whole-exome and whole-transcriptomic sequencing was performed on primary and metastatic samples. Immunostaining for PD-L1 and RNA deconvolution (quanTIseq) was used to explore the tumor immune microenvironment (TME). Real-world clinical and survival outcome metrics were extracted from insurance claims data. RESULTS: MYC expression was 1.61-fold higher (39.8 vs. 24.7; P < 0.0001) among NOTCH1-mutant ACC-I tumors, whereas MYB/L1 fusion rates were similar among ACC-I/II. The median B-cell fraction in the TME was higher among ACC-II (7.1% vs. 5.8%; P < 0.01), although infiltrating T cells subsets were low among either ACC subgroup (both <1%). When pooling systemic treatment categories, ACC-I patients had worse outcomes with available therapies (HR, 3.06; 95% confidence interval, 1.65-5.68; P < 0.01), with no significant difference in overall survival between ACC-I/II based on chemotherapy or VEGFR tyrosine kinase inhibitor exposure in smaller subsets. CONCLUSIONS: We confirmed the previously reported associations with MYC and TP63 in the prognostically relevant subgroups of ACC-I and -II, respectively, and report immunologic differences among these subtypes. Survival outcomes are comparatively worse in ACC-I regardless of treatment type.

Current diagnosis and treatment of salivary gland-type tumors of the lung.

Salivary gland-type tumors of the lung are thought to originate from the submucosal exocrine glands of the large airways. Due to their rare occurrence, reports of their study are limited to small-scale or case reports. Therefore, daily clinical practices often require a search for previous reports. In the last 20 years, several genetic rearrangements have been identified, such as MYB::NF1B rearrangements in adenoid cystic carcinoma, CRTC1::MAML2 rearrangements in mucoepidermoid carcinoma, EWSR1::ATF1 rearrangements in hyalinizing clear cell carcinoma and rearrangements of the EWSR1 locus or FUS (TLS) locus in myoepithelioma and myoepithelial carcinoma. These molecular alterations have been useful in diagnosing these tumors, although they have not yet been linked to molecularly targeted therapies. The morphologic, immunophenotypic, and molecular characteristics of these tumors are similar to those of their counterparts of extrapulmonary origin, so clinical and radiologic differential diagnosis is required to distinguish between primary and metastatic disease of other primary sites. However, these molecular alterations can be useful in differentiating them from other primary lung cancer histologic types. The management of these tumors requires broad knowledge of the latest diagnostics, surgery, radiotherapy, bronchoscopic interventions, chemotherapy, immunotherapy as well as therapeutic agents in development, including molecularly targeted agents. This review provides a comprehensive overview of the current diagnosis and treatment of pulmonary salivary gland tumors, with a focus on adenoid cystic carcinoma and mucoepidermoid carcinoma, which are the two most common subtypes.

Primary pulmonary adenoid cystic carcinoma: A clinicopathological study of 64 patients.

BACKGROUND: This study aimed to investigate the clinicopathological features and prognostic indicators of primary pulmonary adenoid cystic carcinoma (PACC). METHODS: Clinical data were collected from 64 primary PACC patients and analyzed retrospectively at the Tianjin Medical University General Hospital, the West China Hospital of Sichuan University, the First Affiliated Hospital of Guangxi Medical University, and the Bishan Hospital of Chongqing Medical University from January 2003 to August 2023. The 64 patients (28 males and 36 females) were aged from 20 to 73 years, with a median age of 49 years and an average age of 49.3 years. RESULTS: Immunohistochemical staining showed that the tumors expressed CK7, S-100 protein, CK5/6, CD117, and p63. Seven patients underwent fluorescence in situ hybridization (FISH) testing and three were found to have myeloblastosis (MYB) gene translocation. In total, 53 patients underwent surgery, among whom 31 received only surgery and 22 received both surgery and postoperative chemoradiotherapy. In addition, 10 patients received chemoradiotherapy only, while one patient underwent treatment with traditional Chinese medicine. The overall survival rates in the first, third, and fifth years were 98.4%, 95.3%, and 87.5%, respectively. CONCLUSION: Prognostic analysis revealed that age, tumor size, lymph node metastasis status, margin status, and choice of treatment modality significantly influenced the patients' prognosis.

The Efficacy of Immunotherapy and Clinical Utility of Comprehensive Genomic Profiling in Adenoid Cystic Carcinoma of Head and Neck.

Background and Objectives: Adenoid cystic carcinoma (ACC) of the head and neck is generally slow-growing but has a high potential for local recurrence and metastasis to distant organs. There is currently no standard pharmacological treatment for recurrent/metastatic (R/M) ACC, and there are cases in which immune checkpoint inhibitors (ICIs) are administered for ACC according to head and neck squamous cell carcinoma (HNSCC). However, the efficacy of ICIs for ACC remains unclear, and the predictive biomarkers need to be elucidated. Materials and Methods: The Center for Cancer Genomics and Advanced Therapeutics (C-CAT) database enabled the retrospective but nationwide analysis of 263 cases of ACC of the head and neck. Then, we examined and reported four cases of ACC that received ICIs and comprehensive genomic profiling (CGP) in our institution. Results: The C-CAT database revealed that 59 cases out of 263 received ICIs, and the best response was 8% of objective response rate (ORR) and 53% of disease control rate (DCR) (complete response, CR 3%, partial response, PR 5%, stable disease, SD 44%, progressive disease, PD 19%, not evaluated, NE 29%). The tumor mutational burden (TMB) in ACC was lower overall compared to HNSCC and could not be useful in predicting the efficacy of ICIs. Some cases with MYB structural variants showed the response to ICIs in the C-CAT database. A patient with MYB fusion/rearrangement variants in our institution showed long-term stable disease. Conclusions: ICI therapy is a potential treatment option, and the MYB structural variant might be a candidate for predictive biomarkers for immunotherapy in patients with R/M ACC.

Prognostic factors for sublingual gland carcinoma: a population-based Surveillance, Epidemiology and End Results database study.

OBJECTIVE: To identify the clinical features and prognostic factors for sublingual gland carcinoma. METHODS: This was a case-control study. Patients with surgically treated sublingual gland carcinoma were retrospectively included in the Surveillance, Epidemiology and End Results database and divided into adenoid cystic carcinoma (ACC) and non-ACC groups. Primary outcome variables were disease-specific survival (DSS) and overall survival (OS). Prognostic factors for each group were analyzed using Cox models. RESULTS: We included 251 patients (115 men and 136 women). Compared with the non-ACC group, the ACC group had a larger average tumor size and received more adjuvant radiotherapy. In patients with ACC, the pathologic grade had an independent impact on DSS and OS, and patients who were undergoing adjuvant chemotherapy had worse DSS than those who were not receiving chemotherapy. In the non-ACC group, pathologic grade IV, lymph node metastasis, and adjuvant chemotherapy were associated with poor DSS and OS, and tumor extension predicted worsening DSS. CONCLUSIONS: In sublingual gland carcinoma, the pathologic grade and adjuvant chemotherapy were the most important prognostic factors, whereas lymph node metastasis had a negative impact in non-ACC patients but not in ACC patients.

Treatment and outcomes of minor salivary gland cancers of the larynx and trachea: a systematic review.

Objectives: Malignant minor salivary glands carcinomas (MiSGC) of the larynx and trachea are rare tumours and published evidence is sparse. We conducted a systematic review to describe shareable treatment strategies and oncological outcomes of these neoplastic entities. Methods: Full text English manuscripts published from January 1st 2000 to December 14th 2022 were included. Data on demographics, treatments and outcomes were collected. A pooled analysis of 5-year overall survival (OS) was performed. Results: Seventeen articles and 365 patients met the inclusion criteria. The most common subsites involved were subglottic and distal trachea. Adenoid cystic carcinoma was, by far, the most frequent histotype. The first-choice treatment strategy was surgery (86.8%), while adjuvant treatments were delivered in 57.4% of patients. Only 12.9% were treated with definitive radiotherapy with/without chemotherapy. The mean follow-up was 68.3 months. One hundred nine (34.9%) deaths were recorded and 62.4% were cancer-related. Five-year OS ranged from 20% to 100% and, at pooled analysis, it was 83% (range, 78-87%). Conclusions: In case of MiSGC of the larynx and trachea, surgery remains the mainstay of treatment. Adjuvant treatments are frequently delivered. Survival estimates are good overall, but highly heterogeneous.

[Misdiagnosis of adenoid cystic carcinoma of oropharynx: a case report].

Adenoid cystic carcinoma usually occurs in the salivary glands of the head and neck. It is a malignant tumor with a high degree of malignancy, resistance to radiotherapy and chemotherapy and poor prognosis. The clinical course of adenoid cystic carcinoma is slow and easy to be misdiagnosed. The main diagnosis and treatment means are individualized and precise treatment under the multi-disciplinary consultation mode, that is, surgical treatment and radiotherapy and chemotherapy. Adenoid cystic carcinoma is prone to relapse and hematologic metastasis, and the traditional radiotherapy and chemotherapy based therapies have not achieved satisfactory efficacy in the past three decades. How to detect, diagnose and treat early is an urgent task faced by clinicians.

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

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

Failure Patterns Within Different Histological Types in Sinonasal Malignancies: Making the Complex Simple.

OBJECTIVE: To analyze the failure patterns in patients with different histological subtypes of sinonasal malignancies (SNMs). STUDY DESIGN: Retrospectively gathered data. SETTING: Academic university hospital. METHODS: Patients with SNMs treated at a tertiary referral center between January 1999 and January 2019 were included. We assessed the failure patterns within different histological subtypes. RESULTS: The study included 897 patients. The median follow-up time was 100 months. Adenoid cystic carcinoma (ACC) had a moderate risk of developing local recurrence (LR) and distant metastasis (DM). Compared with ACC, squamous cell carcinoma (SCC), adenocarcinoma (AC), soft tissue sarcoma (STS), and mucosal melanoma (MM) were classified as a high LR risk group. For DM, neuroendocrine carcinoma (NEC), STS, and MM were in the high-risk group. CONCLUSIONS: ACC had intermediate local and distant failure risks, while SCC, AC, STS, and MM were at high LR risks. NEC, STS, and MM were at high DM risk.

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

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

Management and outcome of adenoid cystic carcinoma of the major salivary glands: the 22-year experience of a single institution.

BACKGROUND: Prognostic factors and survival rate are difficult to determine for adenoid cystic carcinoma(AdCC) of salivary glands. AIMS/OBJECTIVES: To clarify the clinical characteristics of AdCC and examine factors associated with recurrence and prognosis by histopathological grade classification. MATERIALS AND METHODS: Twenty-five patients with AdCC of the parotid gland and 10 patients with AdCC of the submandibular gland were included. We classified AdCC histopathologically by the proportion of solid components. Clinical features, fine-needle aspiration cytology (FNAC), and patient outcomes were examined according to grade. Factors associated with local recurrence and distant metastases were examined. RESULTS: Age was significantly higher in the grade III group than in the grade I group. The grade III group had significantly higher proportions of patients with cN+, pN+, and perineural invasion. In FNAC, lower-grade groups showed higher rates of correct histopathological type. Five-year disease-specific survival and disease-free survival rates were significantly lower in the grade III than in the grade I. Distant metastases were more common among patients with high-stage and perineural invasion. CONCLUSIONS: Five-year survival is significantly worse in patients with grade III.

Pulmonary adenoid cystic carcinoma: molecular characteristics and literature review.

BACKGROUND: Pulmonary adenoid cystic carcinoma (PACC) is an exceptionally rare salivary gland-type malignant neoplasm. Because of its clinical manifestations, imaging features are not different from other types of non-small cell lung cancer, which is a diagnostic challenge for most doctors. CONCLUSIONS: A review of the literature shows that high amounts of immunohistochemical (IHC) markers, such as CK7, CD117, P63, SMA, CK5/6, and S-100 are helpful for PACC diagnosis. Surgical resection is the main treatment of PACC, but treatment options for advanced PACC patients are limited and the research of molecular targeted drugs is ongoing in advanced cases not eligible for surgery. Currently, research on PACC targeted therapy mainly focuses on the exploration of v-myb avian myeloblastosis virus oncogene homolog (MYB) and its downstream target genes. In addition, median tumor mutation burden and PD-1/PD-L1 were lower in PACC, which may indicate poor efficacy of immunotherapy in PACC patients. This review focuses on the pathologic features, molecular characteristics, diagnosis, treatment and prognosis of PACC to establish a comprehensive understanding of PACC.