Primary adenoid cystic carcinoma of the trachea: clinical outcome of 38 patients after interdisciplinary treatment in a single institution

Treatment outcomes of patients with primary tracheal tumors - analysis of a large retrospective series

OBJECTIVE

Primary tracheal tumors are very rare and their management is not definitely established. Due to its rarity, providing patient care in terms of optimal management poses a considerable challenge. The purpose of this study was to investigate treatment outcomes in patients with these rare tumors.

METHODS

We carried out a retrospective analysis of 89 patients with primary tracheal tumors treated at the Maria Sklodowska-Curie National Research Institute of Oncology in Warsaw, Poland, over sixteen years. The study assessed patient demographics, tumor characteristics and treatment. Different treatment options were compared in terms of overall survival, disease-free survival, and progression-free survival.

RESULTS

A total of 89 patients were included in the study. In the group presented, 45 patients underwent primary radical treatment and 44 were qualified for palliative treatment. Surgical resection was performed in 13 patients out of radically treated patients. The 5 year OS rates in the group of patients who underwent radical treatment and in the group of patients who underwent palliative treatment were 45.9% and 2.3%, respectively. In the group of patients who underwent radical surgical treatment, the 5 year OS was 76.9% compared to 35.8% in the group of patients who underwent nonsurgical treatment.

CONCLUSION

A multidisciplinary team should decide treatment options, including in-depth consideration of surgical treatment options.

[Tracheal Tumours]

Malignant primary tracheal tumours are rare. The most common histological subtypes are squamous cell carcinoma and adenoid cystic carcinoma. These two entities have different prognoses and growth patterns. Tracheobronchoscopy and thoracic sectional imaging are standard diagnostic tools for tumour staging and local evaluation. Complete surgical resection of the affected tracheal segment is the treatment of choice for limited disease without distant metastases. Incomplete gross tumour resection with additional irradiation is an acceptable therapeutic option for adenoid cystic carcinoma. Interventional endoscopy with tumour debulking or tracheal stenting and/or definitive mediastinal radiotherapy are treatment alternatives in either a locally advanced or palliative setting.

Integrated endoscopic treatment of primitive unresectable tracheal tumor: the INTACT retrospective cohort study

Background

Primitive tracheal tumors represent a rare entity whose management, when unresectable, remains challenging. Primary aim of this study was to explore the survival and the factors influencing prognosis of patients with unresectable primitive tracheal tumor undergoing multimodal treatment integrating interventional bronchoscopy and radiotherapy.

Methods

This retrospective cohort study was conducted at the University Hospital of Modena (Italy) over a 12-year period (January 2010 to January 2022) analyzing patients with unresectable primary tracheal tumor receiving interventional bronchoscopy treatment followed by radiotherapy. Survival analysis was conducted for the whole population and according to histology, development of metastasis, stent placement and the onset of disease relapse. The raw and independent association between potential risk factor and 5-year mortality and the reported complications were investigated.

Results

A total of 12 patients were included. Five-year survival rate was 42% with a median survival time of 26.7 (interquartile range, 4.1-82) months. Survivors showed a higher prevalence of cystic-adenoid histology (80% vs. 14%), while patients who were dead at 5 years were those with a more advanced T (prevalence of T2: 71% vs. 0%) and a lower response to first line treatment (57% vs. 0%). Treatment complications accounted for stent dislocation (33%) and the onset of granuloma (18%), while no major side effects were reported. The presence of cystic-adenoid histology resulted in significantly improved 5-year survival rate (80% vs. 14%). The onset of distal metastasis, the occurrence of disease relapse and the placement of tracheal stent did not result significantly associated with lower survival. Among analysed variables, only the presence of cystic-adenoid histology resulted independently associated with survival (odds ratio =0.1, P=0.04).

Conclusions

Multimodal treatment including interventional bronchoscopy and associated radiotherapy for unresectable primary tracheal tumors seems not burdened by significant complications and may provide benefits in terms of survival for those patients with cystic-adenoid histology.

Tracheal adenoid cystic carcinoma with microscopic positive margin-how we approached with a systematic analysis review of its management

Purpose

Adenoid cystic carcinoma (ACC) of the trachea is a rare malignancy. We report a patient with ACC who underwent multimodal management including tracheal resection. A systematic review was also conducted on tracheal resection for ACC.

Methods

A literature search was conducted on MEDLINE, Embase, and PubMed using the search terms "trachea AND adenoid cystic carcinoma AND (surgery OR resection)" and articles from 2000 to August 2021 were identified. A total of 29 journal articles were included in the review.

Results

A total of 403 patients underwent surgery for tracheal ACCs. The mean age was 48.1 years and 54.7% were female. The commonest anatomical location was the lower trachea (46.9%). The mean time from symptom onset to diagnosis was 16.6 months with the commonest symptom being dyspnoea (52%). Fifty-eight percent of the patients had intraluminal growth. Tracheal resection (46.2%) and access via thoracotomy (41.4%) were the commonest procedures described. The mean length of trachea resected was 39.2 mm and the mean tumour size was 31.5 mm. 16.8% of lymph nodes were involved and 73.8% of cases had positive resection margins. The overall complication rate was 1.4-5.4% and the in-hospital mortality rate was 9.8%. The overall survival reported was 61.7% at 5 years and 54.6% at 10 years.

Conclusion

Surgical resection followed by adjuvant radiotherapy is the mainstay in the treatment of tracheal ACC, notwithstanding the high rates of involved margins. Achieving tension-free anastomosis should be the first priority given the favourable response of adjuvant therapies in reducing recurrence rate and improving overall survival.

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.

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.

Rare but clinically important salivary gland-type tumor of the lung: A review

Salivary gland-type tumor (SGT) of the lung, which arises from the bronchial glands of the tracheobronchial tree, was first recognized in the 1950s. SGT represents less than 1% of all lung tumors and is generally reported to have a good prognosis. Mucoepidermoid carcinoma (MEC) and adenoid cystic carcinoma (ACC) are the two most common subtypes, comprising more than 90% of all SGTs. The reported 5-year survival rate of patients with SGT is 63.4%. Because this type of tumor develops in major bronchi, patients with SGT commonly present with symptoms of bronchial obstruction, including dyspnea, shortness of breath, wheezing, and coughing; thus, the tumor is usually identified at an early stage. Most patients are treated by lobectomy and pneumonectomy, but bronchoplasty or tracheoplasty is often needed to preserve respiratory function. Lymphadenectomy in the surgical resection of SGT is recommended, given that clinical benefit from lymphadenectomy has been reported in patients with MEC. For advanced tumors, appropriate therapy should be considered according to the subtype because of the varying clinicopathologic features. MEC, but not ACC, is less likely to be treated with radiation therapy because of its low response rate. Although previous researchers have learned much from studying SGT over the years, the diagnosis and treatment of SGT remains a complex and challenging problem for thoracic surgeons. In this article, we review the diagnosis, prognosis, and treatment (surgery, chemotherapy, and radiotherapy) of SGT, mainly focusing on MEC and ACC. We also summarize reports of adjuvant and definitive radiation therapy for ACC in the literature.

Pulmonary Adenoid Cystic Carcinoma Mimicking Asthma-Like Symptoms: A Case Report and Literature Review

Introduction

Pulmonary adenoid cystic carcinoma (PACC) is a rare, low-grade malignant salivary gland-type tumor characterized by a dormant onset and slow progression, often leading to misdiagnosis. Due to its rarity, limited cases have been reported in the literature. This report aimed to enhance clinicians' understanding of this infrequent disease.

Case Presentation

We present the case of a 41-year-old female patient diagnosed with PACC. Our report provides a comprehensive analysis of the patient's imaging, pathology, and treatment, with a particular focus on immunohistochemical results. Importantly, we emphasize the significance of considering foreign bodies and tumors in the bronchus when encountering asthma-like symptoms unresponsive to conventional treatments. Due to the uncertain etiology and pathophysiology of PACC, there are currently no established guidelines for chemotherapy and radiotherapy.

Conclusion

PACC predominantly manifests as bronchial lesions without significant clinical heterogeneity. Therefore, it is crucial to consider foreign bodies and tumors in the bronchus when dealing with asthma-like symptoms, especially in patients without chronic lung disease who do not respond to anti-infective, antispasmodic, and antiasthmatic treatments. Additionally, meticulous examination of lesions is essential for timely diagnosis and intervention, ultimately improving patient survival rates.

Long-term follow-up of unresectable adenoid cystic carcinoma of the trachea and bronchus treated with high-dose proton beam therapy: A report of two cases

Adenoid cystic carcinoma (ACC) of the trachea is a rare disease that is slow growing and has a risk of distant metastasis. The standard treatment for ACC of the trachea is surgery, but this tumor is often unresectable. In definitive radiotherapy using photons for unresectable ACC of the trachea, it is sometimes difficult to deliver a sufficient dose to the target without exceeding the tolerable dose to the surrounding normal tissues. Here, we report two cases of ACC of the trachea that received a high dose (74 Gy [relative biological effectiveness]) of proton beam therapy and achieved long-term survival.

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.

A rare mimic of adult-onset asthma: Case report and review of the literature

Adult-onset asthma is extremely variable in its phenotypic presentation and has gained notoriety for the overall poorer treatment outcomes even on standard asthma therapy. Tracheal tumours are rare but when present, exhibit asthma-like phenomenon in adult patients posing great diagnostic challenges. We report two adult patients with tracheal adenoid cystic tumours who were initially treated for adult-onset asthma. Patient 1, a 45-year-old man was diagnosed and managed for adult-onset asthma over a 12 months period without satisfactory control of his symptoms. Following a late episode of hemoptysis, a chest Computed Tomography (CT) scan done revealed an occluding tracheal tumour. Patient 2 is a 28-year-old female who was diagnosed with adult-onset asthma for over 2 years with poor symptom control despite optimal asthma therapy. She developed cough-induced subcutaneous emphysema for which a chest CT scan revealed a tracheal mass. The patient had surgery with incomplete resection of tumour and adjuvant radiotherapy.

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.

The impact of surgery and age on mortality with primary trachea malignant tumors: a retrospective study based on propensity-score matching analysis

PURPOSE

This study aimed to explore the survival significance of surgery and age on the prognosis of patients with primary trachea malignancies.

METHODS

The entire cohort of 637 patients with primary malignant trachea tumors was used to perform the main analyses. The data of those patients were from a public database. Overall survival (OS) curves were drawn by the Kaplan-Meier method and compared by the Log-rank test. The univariable and multivariable Cox regression analyses calculated the hazard ratio (HR) and 95% confidence interval (CI) for overall mortality. The propensity-score matching analysis was used to reduce the selection bias.

RESULTS

Age, surgery, histological type, N classification, M classification, marital status, and tumor grading were identified as independent prognostic factors after eliminating confounding factors. The results of the Kaplan-Meier method revealed that patients with age < 65 had a survival advantage over those with age ≥ 65 (HR = 1.908, 95% CI 1.549-2.348, P < 0.001). The 5-year OS rates were 28% and 8% in the group with age < 65 and age ≥ 65, respectively (P < 0.001). Cases with surgery had better survival over patients without surgery (HR = 0.372, 95% CI 0.265-0.522, P < 0.001). Compared with patients who did not undergo operations, patients with surgery had a higher median survival time (20 vs. 174 months). For patients with surgery, young age was considered a survival-promoting factor (HR 2.484; 95% CI 1.238-4.983, P = 0.010).

CONCLUSION

We suggested that age and surgery were the independent prognostic factors in patients with primary malignant trachea tumors. Besides, age serves as an essential indicator for evaluating the prognosis of postoperative patients.

TACC diagnosed by transoesophageal endoscopic ultrasonography: A case report

BACKGROUND

Primary adenoid cystic carcinoma in the trachea (TACC) is a rare tumour. Tracheal bronchoscopy is always chosen as a routine approach to obtain a pathological diagnosis, but it can be associated with an increased risk of asphyxia.

CASE SUMMARY

We describe a case of TACC in a patient evaluated by chest computed tomography (CT) with three-dimensional reconstruction imaging and diagnosed by transoesophageal endoscopic ultrasonography. The pathological diagnosis confirmed tracheal adenoid cystic carcinoma.

CONCLUSION

We highlight the importance of CT and provide a successful exploration of transoesophageal biopsy as a safe alternative approach.

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.

Adenoid cystic carcinoma of the trachea mimicking asthma

Adenoid cystic carcinoma (ACC) is primarily a salivary gland tumour that rarely involves the respiratory tract. A 58-year-old lady was admitted with worsening dyspnoea, cough and wheezing for 2 days. CT pulmonary angiogram was done due to persistent dyspnoea which revealed a 12 mm mass protruding into the posterior aspect of the trachea with multiple enlarged nodes. There was a complete collapse of the left lower lobe and right middle lobe with right upper lobe pulmonary embolism which was thought to be contributing to her hypoxia. She was struggling with secretion clearance and initial measures to clear her secretions were not successful. She was treated with a tracheal stent, followed by an interval endoscopic ultrasound-guided biopsy of the tracheal wall lesion which revealed ACC. She was referred to cardiothoracic surgeons for excision of the tumour after discussing in MDT. Surgery followed by radiotherapy is advised in cases with incomplete resection margins.

Primary adenoid cystic carcinoma of the trachea: an elusive diagnosis of chronic dyspnoea

Primary adenoid cystic carcinoma (ACC) of the trachea is a rare entity, with a 5-year survival between 50% and 80% for resectable cases and 30% in case of unresectable disease. We report a case of a primary ACC on a woman in her 70s that presented with a drawn-out history of dyspnoea. She was diagnosed with an unresectable obstructive tumour of the trachea, which required the placement of a Y-shaped stent. The patient underwent concomitant chemoradiotherapy, with partial response, and is still in follow-up, without evidence of disease progression.

Therapeutic bronchoscopy followed by sequential radiochemotherapy in the management of life-threatening tracheal adenoid cystic carcinoma: a case report

Background

Adenoid cystic carcinoma of the lung is a distinctive salivary-gland-type malignant epithelial neoplasm that rarely presents as a primary tumor of the respiratory tract. Complete surgical resection remains the treatment of choice for adenoid cystic carcinoma. We present a case of large ACC tumors that caused severe central airway obstruction and were effectively treated with therapeutic bronchoscopy followed by radiotherapy and chemotherapy.

Case presentation

A 31-year-old Malay Indonesian female patient who was a nonsmoker and had no family history of cancer was admitted to the emergency ward because of worsening breathlessness accompanied by stridor since 1 week prior. Chest computed tomography revealed segmental atelectasis of the left lung; a mass on the left main bronchus, with infiltrates in segments 1, 2, and 3 of the left lung; and consolidation in the left inferior lobe, with narrowing of the main left bronchus. Lobulated masses obstructing almost the entire distal trachea up to the carina and the entire left main bronchus were found on bronchoscopy. Owing to the large tumors causing severe central airway obstruction, the medical team decided to perform central airway mass removal through rigid bronchoscopy. A neodymium-doped yttrium-aluminum-garnet laser was used first to facilitate mass shrinkage. After the laser treatment, mechanical mass removal using a rigid scope was performed. The tracheal and carinal lumens were opened to > 50% of their diameter, with the left main bronchus lumen opened only slightly. After the treatment, the patient was stable, and no stridor was found. Adjuvant intensity-modulated radiotherapy and chemotherapy were performed after the therapeutic bronchoscopy. At the end of the entire treatment, reevaluation by thoracic computed tomography scan and bronchoscopy revealed no remaining mass.

Conclusions

In cases of nonresectable large adenoid cystic carcinoma tumors with life-threatening central airway obstruction, therapeutic bronchoscopy followed by sequential radiochemotherapy might achieve a complete response outcome.

Adenoid Cystic Carcinoma of Lobar Bronchial Origin: 20-Year Experience at a Single Institution

BACKGROUND

Pulmonary adenoid cystic carcinoma (ACC) is a rare type of lung malignancy. The prevalence of ACC of lobar bronchial origin is lower than that of other lung malignancies, and studies investigating it are lacking. This study aimed to evaluate survival of patients with ACC of the lobar bronchus after surgical resection and to explore its prognostic factors.

METHODS

Between January 2000 and December 2019, 35 patients at the National Cancer Center/Cancer Hospital with a diagnosis of ACC of the lobar bronchus were included in the retrospective analysis.

RESULTS

During a median follow-up period of 61 months (range, 10-194 months), the analysis showed a 5-year overall survival (OS) rate of 81.4%, a 5-year locoregional recurrence-free survival rate of 84.0%, and 5-year disease-free survival rate of 60.1%. The univariate analysis exclusively identified the surgical margin as a predictor of OS, and survival was significantly longer for the patients with negative surgical margins than for those with positive surgical margins (R0 vs. R1: 94.4% vs. 66.0%; p = 0.014). Adjuvant radiotherapy was administered to most of the patients with positive surgical margins, which might have contributed to prolonged OS (R0 vs. R1+RT: 94.4% vs. 66.7%, p = 0.173; R0 vs. R1+no RT: 94.4% vs. 62.5%, p = 0.007).

CONCLUSIONS

For ACC of lobar bronchial origin, complete resection is the radical treatment, and the OS rate was significantly higher for the R0 patients than for the R1 patients. Adjuvant radiotherapy for patients with R1 may prolong survival.

Flourish of Proton and Carbon Ion Radiotherapy in China

Proton and heavy ion therapy offer superior relative biological effectiveness (RBE) in the treatment of deep-seated tumors compared with conventional photon radiotherapy due to its Bragg-peak feature of energy deposition in organs. Many proton and carbon ion therapy centers are active all over the world. At present, five particle radiotherapy institutes have been built and are receiving patient in China, mainly including Wanjie Proton Therapy Center (WPTC), Shanghai Proton Heavy Ion Center (SPHIC), Heavy Ion Cancer Treatment Center (HIMM), Chang Gung Memorial Hospital (CGMH), and Ruijin Hospital affiliated with Jiao Tong University. Many cancer patients have benefited from ion therapy, showing unique advantages over surgery and chemotherapy. By the end of 2020, nearly 8,000 patients had been treated with proton, carbon ion or carbon ion combined with proton therapy. So far, there is no systemic review for proton and carbon ion therapy facility and clinical outcome in China. We reviewed the development of proton and heavy ion therapy, as well as providing the representative clinical data and future directions for particle therapy in China. It has important guiding significance for the design and construction of new particle therapy center and patients’ choice of treatment equipment.

Biological Rationale and Clinical Evidence of Carbon Ion Radiation Therapy for Adenoid Cystic Carcinoma: A Narrative Review

Adenoid cystic carcinoma (ACC) is a rare, basaloid, epithelial tumor, arising mostly from salivary glands. Radiation therapy can be employed as a single modality for unresectable tumors, in an adjuvant setting after uncomplete resection, in case of high-risk pathological features, or for recurrent tumors. Due to ACC intrinsic radioresistance, high linear energy transfer (LET) radiotherapy techniques have been evaluated for ACC irradiation: while fast neutron therapy has now been abandoned due to toxicity concerns, charged particle beams such as protons and carbon ions are at present the beams used for hadron therapy. Carbon ion radiation therapy (CIRT) is currently increasingly used for ACC irradiation. The aim of this review is to describe the immunological, molecular and clinicopathological bases that support ACC treatment with CIRT, as well as to expose the current clinical evidence that reveal the advantages of using CIRT for treating ACC.

Physics and biomedical challenges of cancer therapy with accelerated heavy ions

Radiotherapy should have low toxicity in the entrance channel (normal tissue) and be very effective in cell killing in the target region (tumour). In this regard, ions heavier than protons have both physical and radiobiological advantages over conventional X-rays. Carbon ions represent an excellent combination of physical and biological advantages. There are a dozen carbon-ion clinical centres in Europe and Asia, and more under construction or at the planning stage, including the first in the USA. Clinical results from Japan and Germany are promising, but a heated debate on the cost-effectiveness is ongoing in the clinical community, owing to the larger footprint and greater expense of heavy ion facilities compared with proton therapy centres. We review here the physical basis and the clinical data with carbon ions and the use of different ions, such as helium and oxygen. Research towards smaller and cheaper machines with more effective beam delivery is necessary to make particle therapy affordable. The potential of heavy ions has not been fully exploited in clinics and, rather than there being a single 'silver bullet', different particles and their combination can provide a breakthrough in radiotherapy treatments in specific cases.

Risk-score model to predict prognosis of malignant airway obstruction after interventional bronchoscopy

Background

Interventional bronchoscopy exhibits substantial effects for patients with malignant airway obstruction (MAO), while little information is available regarding the potential prognostic factors for these patients.

Methods

Between October 31, 2016, and July 31, 2019, a total of 150 patients undergoing interventional bronchoscopy and histologically-confirmed MAO were collected, in which 112 eligible participants formed the cohort for survival study. External validation cohort from another independent institution comprised 33 MAO patients with therapeutic bronchoscopy. The least absolute shrinkage and selection operator regression (LASSO) was applied to the model development dataset for selecting features correlated with MAO survival for inclusion in the Cox regression from which we elaborated the risk score system. A nomogram algorithm was also utilized.

Results

In our study, we observed a significant decline of stenosis rate after interventional bronchoscopy from 71.7%±2.1% to 36.6%±2.7% (P<0.001) and interventional bronchoscopy dilated airway effectively. Patients in our study undergoing interventional bronchoscopy had a median survival time of 614.000 days (95% CI: 269.876–958.124). Patients receiving distinct therapeutic methods of interventional bronchoscopy had different prognosis (P=0.022), and patients receiving treatment of electrocoagulation in combination with stenting and electrosurgical snare had worse survival than those receiving other options. Multivariate Cox analysis revealed that nonsmoking status, adenoid cystic carcinoma, and low preoperative stenosis length, as independent predictive factors for better overall survival (OS) of MAO patients. Then, the nomogram based on Cox regression and risk score system based on results from LASSO regression were elaborated respectively. Importantly, this risk score system was proved to have better performance than the nomogram and other single biomarkers such as traditional staging system (area under the curve 0.855 vs. 0.392–0.739). Survival curves showed that patients with the higher risk-score had poorer prognosis than those with lower risk-score (third quantile of OS: 126.000 days, 95% CI: 73.588–178.412 vs. 532.000 days, 95% CI: 0.000–1,110.372; P<0.001).

Conclusions

Nonsmoking status, adenoid cystic carcinoma, and low preoperative stenosis length, were independent predictive factors for better OS of MAO patients. We proposed a nomogram and risk score system for survival prediction of MAO patients undergoing interventional bronchoscopy with good performance.

Definitive carbon ion radiotherapy for tracheobronchial adenoid cystic carcinoma: a preliminary report

Background

Tracheobronchial adenoid cystic carcinoma (TACC) is a rare tumour. About one-third of patients miss their chance of surgery or complete resection as it is mostly detected in the advanced stage; hence, photon radiotherapy (RT) is used. However, the outcomes of photon RT remain unsatisfactory. Carbon ion radiotherapy (CIRT) is thought to improve the therapeutic gain ratio; however, the outcomes of CIRT in TACC are unclear. Therefore, we aimed to assess the effects and toxicities of CIRT in patients with TACC.

Methods

The inclusion criteria were as follows: 1) age 18–80 years; 2) Eastern Cooperative Oncology Group Performance Status 0–2; 3) histologically confirmed TACC; 4) stage III–IV disease; 5) visible primary tumour; and 6) no previous RT history. The planned prescription doses of CIRT were 66–72.6 GyE/22–23 fractions. The rates of overall survival (OS), local control (LC), and progression-free survival (PFS) were calculated using the Kaplan-Meier method. Treatment-induced toxicities and tumour response were scored according to the Common Terminology Criteria for Adverse Events and Response Evaluation Criteria in Solid Tumors, respectively.

Results

Eighteen patients with a median age of 48 (range 30–73) years were enrolled. The median follow-up time was 20.7 (range 5.8–44.1) months. The overall response rate was 88.2%. Five patients developed lung metastasis after 12.2–41.0 months and one of them experienced local recurrence at 31.9 months after CIRT. The rates of 2-year OS, LC, and PFS were 100, 100, and 61.4%, respectively. Except for one patient who experienced grade 4 tracheal stenosis, which was relieved after stent implantation, no other ≥3 grade toxicities were observed.

Conclusions

CIRT might be safe and effective in the management of TACC based on a short observation period. Further studies with more cases and longer observation are warranted.

Expanding role of radiotherapy in adenoid cystic carcinoma of the tracheobronchial tree: a new horizon

BACKGROUND

Primary adenoid cystic carcinomas (ACCs) of central trachea-bronchi system are rare and heterogeneous tumors. Definitive radiotherapy (RT) is the recommended treatment in surgically unresectable or incomplete resection or in the presence of severe comorbidities.

OBJECTIVE

To evaluate the clinical features and outcomes of patients with ACC of trachea-bronchi treated with radiotherapy.

METHODS

Retrospective medical records review was done in all patients with histologically confirmed ACC of trachea-bronchi between January 2010 and December 2019. Patient disease and treatment characteristics and toxicity data were analyzed. Overall survival (OS), local recurrence-free survival (LRFS), and distant metastasis-free survival (DMFS) were computed using Kaplan-Meier method (log-rank test).

RESULTS

Nineteen patients (10 women and 9 men) were included in this analysis with median age of 40 years (range, 14-70). Of these patients, 63.2% (n = 12) presented in stage IV disease. Twelve and three patients received definitive (median dose 67.8 Gy) and adjuvant (median dose 50 Gy) RT, respectively. The median follow-up was 42.5 months (range, 4-120); 15 patients were alive and 4 were dead at that time. Local recurrence or progression was observed in 52.6% and distant metastasis found in 47.3% of patients. The 5-year OS, LRFS, and DMFS for all patients were 81.2%, 52.8%, and 39.6%, respectively. Baseline lymph node involvement showed significant impact on OS (56.3% vs 100%, p = 0.011). Among patients receiving definitive RT, patients with higher RT dose (⩾66 Gy) had significantly better survival outcomes (5-year LRFS: 75% vs 16.7%, p = 0.013).

CONCLUSION

Definitive RT is an exemplary treatment for unresectable disease. Higher dose is recommended to improve long-term outcomes.

Intensity modulated radiation therapy may improve survival for tracheal-bronchial adenoid cystic carcinoma: A retrospective study of 133 cases

PURPOSES

This study aimed to evaluate the role of radiotherapy (RT) and intensity modulated radiation therapy (IMRT) in adjuvant and definitive settings of tracheal-bronchial adenoid cystic carcinoma (TACC) treatment.

MATERIALS/METHODS

TACC patients (n = 133) treated with surgery and/or RT curatively in our institution between January 1^st, 1984 and December 31^st, 2017 were analyzed retrospectively.

RESULTS

Among the 116 patients undergoing surgery, 50 (43.1 %) achieved complete resections and 66 (56.9 %) had positive surgical margins. For patients with positive margins, overall adjuvant RT was correlated with no significantly improved OS (10-year: 58.0 % vs. 47.9 %; P =  0.340) and a slight LRFS benefit (5-year: 81.9 % vs.75.6 %; P =  0.056), but adjuvant IMRT showed significant superiority in both OS (10-year: 82.9 % vs. 47.9 %; P =  0.031) and LRFS (5-year: 100.0 % vs. 75.6 %; P =  0.001) in comparison with no postoperative RT. Multivariate analysis also identified adjuvant IMRT as a significant favorable factor with OS (HR = 0.186, 95 %CI: 0.039-0.883; P =  0.034). For 17 patients receiving definitive RT, IMRT achieved promising 5-year OS of 88.9 % and LRFS of 64.3 %, yet no significant difference from non-IMRT group was reached (P = 0.447 and 0.706). Different therapies presented no significantly different impact on DMFS, whilst DMFS explained more of the OS variances (P < 0.001, R² = 0.480) than LRFS (P < 0.001, R² = 0.323).

CONCLUSION

IMRT could confer greatly improved OS and LRFS in postoperative setting for TACC patients with positive surgical margins. IMRT was also a good therapeutic option for definitive TACC with promising survival and local control.

Contrast-enhanced CT longitudinal tail sign as a marker of positive resection margins in adenoid cystic carcinoma of the central airway

Background

Due to submucosal infiltration’s biological nature along the airway, adenoid cystic carcinoma (ACC) frequently leaves positive surgical margins. This study evaluated the clinicopathologic, and computed tomography (CT) features for predicting surgical margin status in central airway ACC.

Methods

We retrospectively analyzed the files of 71 patients with ACC of the central airway proven by histopathology and surgery who had presented between January 2010 and December 2018. All patients were classified into positive and negative surgical margin groups according to margin status. Univariate analysis and multivariable logistic regression models were then performed to compare demography, histopathology, and CT characteristics between ACC patients with positive and negative margins.

Results

After surgical resection, 59 (83.1%) patients had positive margins, and 12 (16.9%) had negative margins. The contrast-enhanced CT (CECT) longitudinal tail sign (LTS) was identified in 55 of 59 (93.2%) patients with positive margins and was the only feature that had a significant association with positive margins (odds ratio 41.250, 95% CI: 7.886–215.767; P<0.001). Moreover, positive margins in upper or/and lower directions were associated with the LTS in corresponding directions (P<0.001).

Conclusions

Most central airway ACC patients exhibited positive margins following surgery. The appearance of the LTS on CECT was significantly associated with positive margins and could help preoperatively predict the submucosal invasion of ACC.

CT diagnosis and prognosis prediction of tracheal adenoid cystic carcinoma

PURPOSE

To evaluate computed tomography (CT) features and establish a predictive model for the clinical diagnosis and prognosis of tracheal adenoid cystic carcinoma (ACC).

METHOD

From January 2010 to December 2018, 82 patients with tracheal tumors, including 46 patients with ACC confirmed by surgery and histopathology, were enrolled in this study. These patients' clinicopathologic information, CT features and survival outcomes were recorded and analyzed. Independent predictors of diagnosis and prognosis of tracheal ACC were determined by both univariate and multivariate analyses.

RESULTS

Compared with tracheal non-ACC patients, univariate analysis showed that ACC patients were more likely to have extensive longitudinal length (p < 0.001) and to appear as annular wall thickening (p = 0.001), transmural growth (p = 0.036), poorly defined border (p = 0.003) and mild enhancement (p = 0.001). Multivariate logistic analysis showed that longitudinal length and enhancement degree were independent predictors of tracheal ACC. The 3-year and 5-year disease-free survival (DFS) were 75.7 % and 64.5 %, respectively. Longitudinal length (≥ 34 mm), transverse length (≥ 20 mm) and transmural growth were associated with poor DFS in univariate analysis. After multivariate adjustment, only transverse length (≥ 20 mm) was an adverse prognostic factor for DFS (hazard ratio = 4.594, 95 % confidence interval = 1.240-17.017; p = 0.022).

CONCLUSIONS

CT longitudinal length and enhancement degree of tumors showed satisfactory discrimination for tracheal ACC. Excessive CT transverse length might be an unfavorable indicator for ACC recurrence and could be helpful for predicting the survival outcomes of ACC at the initial diagnosis.

Patterns of Care and Outcomes of Primary Adenoid Cystic Carcinoma of the Trachea

OBJECTIVE

Primary tracheal malignancies are relatively rare cancers, representing 0.1% to 0.4% of all malignancies. Adenoid cystic carcinoma (ACC) is the second most common histology of primary tracheal malignancy, after squamous cell carcinoma. This study aims to analyze demographic characteristics and potential influencing factors on survival of tracheal ACC (TACC).

METHODS

This was a retrospective cohort study utilizing the National Cancer Database (NCDB). The NCDB was queried for all cases of TACC diagnosed from 2004 to 2016 (n = 394). Kaplan-Meier (KM) and Cox proportional-hazards models were used to determine clinicopathological and treatment factors associated with survival outcomes.

RESULTS

Median age of diagnosis was 56 (IQR: 44.75-66.00). Females were affected slightly more than males (53.8% vs 46.2%). The most prevalent tumor diameter range was 20 to 39 mm (34.8%) followed by greater than 40 mm in diameter (17.8%). Median overall survival (OS) was 9.72 years with a 5- and 10-year OS of 70% and 47.5%, respectively. Localized disease was not associated with a survival benefit over invasive disease (P = .388). The most common intervention was surgery combined with radiation therapy (RT) at 46.2%, followed by surgery alone (16.8%), and standalone RT (8.9%). When adjusting for confounders, surgical resection was independently associated with improved OS (HR 0.461, 95% CI 0.225-0.946). Tumor size greater than 40 mm was independently associated with worse OS (HR 2.808; 95% CI 1.096-7.194).

CONCLUSION

Our data suggests that surgical resection, possibly in conjunction with radiation therapy, is associated with improved survival, and tumor larger than 40 mm are associated with worse survival.

Exploration of High-Grade Transformation and Postoperative Radiotherapy on Prognostic Analysis for Primary Adenoid Cystic Carcinoma of the Head and Neck

Background

Despite Adenoid cystic carcinoma (ACC) with cribriform or tubular components being recognized as a potentially indolent malignancy, ACC displaying solid or, more rarely, high-grade transformation (HGT) components is considered a more aggressive variant of the disease. As it is difficult to measure the proportion of the solid component objectively, and the role of HGT in the current grading system remains unclear, the prognostic influence of tumor grading remains controversial. In addition, postoperative radiotherapy (PORT) has been proven to be effective in local control of ACC of the head and neck (ACCHN) with a high rate of nerve invasion and close surgical margin. However it remains to be explored that whether PORT could improve the survival of patients with ACC, particularly those with HGT.

Methods

A series of 73 surgically treated primary ACCHN cases were retrospectively accessed. Immunohistochemical staining was performed to observe the biphasic ductal-myoepithelial differentiation and to identify the HGT components of ACC for tumor grading. The correlation between tumor grading and clinicopathological characteristics was analyzed. Univariate and multivariate prognostic analysis were performed for progression-free survival (PFS) and overall survival (OS).

Results

Of the 73 included cases, 47 were grade I-II ACC and 26 were grade III ACC. Among the grade III cases, 14 with loss of biphasic ductal-myoepithelial differentiation identified by immunostaining were classified as HGT, and could be distinguished from conventional grade III cases. These HGT cases were correlated with a high propensity of lymph node metastases and more advanced stage. Univariate analysis demonstrated that tumor grading, perineural invasion, T stage, stage groups, and PORT were predictors for PFS, whereas tumor grading, margin status, and PORT were predictors for OS. However, only tumor grading and PORT were independent predictors for PFS and OS. The patients with HGT had significantly worse prognosis than those with conventional ACC. Moreover, disease progression tended to occur more frequently in younger patients. Among the patients with HGT, those who received PORT had a longer median survival time than those who did not.

Conclusion

HGT ACC identified by loss of biphasic differentiation should be considered in tumor grading. Tumor grading and PORT were independent predictors for disease progression and OS in surgically treated ACCHN patients.

Case Report: Efficacy of Pyrotinib in ERBB2 Amplification Pulmonary Adenoid Cystic Carcinoma

Primary pulmonary adenoid cystic carcinomas are salivary tumors that are low-grade malignant and prone to recurrence and metastasis. Surgery is currently the main treatment, but there is no standard with regard to postoperative adjuvant therapy. Adenoid cystic carcinoma is more sensitive to radiotherapy and patients benefit less from chemotherapy, but few studies have focused on targeted therapy, and their conclusions are inconsistent. With respect to primary pulmonary adenoid cystic carcinoma, large-scale studies cannot be conducted due to its low incidence, and studies on the targeted therapy of it are very scarce. A few case reports indicate that targeted therapy can be effective however, suggesting that it may be a good option. The current report is the first on the occurrence of human epidermal growth factor receptor 2 amplification in pulmonary adenoid cystic carcinoma. The patient was treated with pyrotinib for 6 months and achieved stable disease.

Adenoid cystic carcinoma and chronic lymphocytic leukaemia: synchronous presentations in the lung

A 59-year-old male active smoker presented with a 6-month history of cough and breathlessness and was found to have a right upper lobe mass. Histology revealed this to be an adenoid cystic carcinoma (ACC) of the lung, while local lymph node dissection revealed a synchronous diagnosis of chronic lymphocytic leukaemia (CLL). The connection between CLL and solid organ malignancy is well documented, but the reporting of ACC in this context is novel. Mechanisms linking the two processes are revealed with the possibility of causality, and heightened vigilance for the development of primary lung tumours in CLL, and their management, is recommended.

Clinical features, treatment and outcomes in patients with tracheal adenoid cystic carcinoma: a systematic literature review

Background

Primary tracheal adenoid cystic carcinoma (TACC) is rare and originates from the minor salivary gland. Biologically, TACC results in delayed presentation, and the therapeutic effects of multimodal treatment differ across individuals. This study aimed to review cases of TACC to identify clinical features, imaging modalities, treatment, and patient outcomes across follow-ups.

Methods

The PubMed, Web of Science and MEDLINE databases were searched to identify articles reporting cases of TACC. The study variables included in the analysis were patient demographics, biological characteristics, presenting symptoms, imaging modalities, treatments, follow-up times and survival outcomes.

Results

A total of 76 articles and 1252 cases were included in this review. The most common presenting symptom was dyspnoea (86.0%), followed by cough (58.0%). Surgery alone (40.9%), surgery with postoperative radiotherapy (36.4%) and radiotherapy alone (19.2%) were used most frequently treatments modalities. Of the 1129 cases with disease control and survival data, there was no evidence of disease in 78.7%, local recurrence was reported in 3.8%. Distant metastasis rate was 24.9% of 418 reported cases, lung (44.2%) was the most commonly involved organ. The 5, 10 years survival rate of patients treated with surgery alone and surgery with postoperative radiotherapy were 86.4%, 55.6% and 97.3%, 44.4%, respectively.

Conclusion

TACC most common presenting symptoms were dyspnoea, cough and shortness of breath. Surgery alone and surgery with postoperative radiotherapy are predominant treatment modalities. Both seems to provide a good result in term of disease control and long-term survival rate in patients with TACC.

Impact of Tumor Site and Adjuvant Radiotherapy on Survival of Patients with Adenoid Cystic Carcinoma: A SEER Database Analysis

Adenoid cystic carcinoma (ACC) is a rare salivary gland tumor, displaying aggressive behavior with frequent recurrence and metastasis. Little information exists regarding the impact of clinicopathological parameters and adjuvant radiotherapy (aRT) on ACC disease specific (DSS) and overall survival (OS). We extracted demographic, treatment, and survival information of 1439 patients with major or minor intraoral salivary gland ACC from the Surveillance, Epidemiology, and End Results (SEER) database. The associations between tumor characteristics and aRT with OS and DSS were estimated using hazard ratios (HR) and 95% confidence intervals (CI). Submandibular gland ACCs had the worst prognosis (adjusted DSS HR = 1.48; 95% CI = 0.99-2.20, compared to parotid), and this difference was more pronounced among patients with advanced-stage tumors (adjusted DSS HR = 1.93; 95% CI = 1.13-3.30). aRT was associated with increased overall survival only among stage III submandibular ACC patients (HR = 0.64; 95% CI = 0.42-0.98) and had no benefit in any other group. In conclusion, submandibular gland ACC carries a worse prognosis than other gland subsites and may benefit from aRT. The different outcomes between submandibular gland and other major or minor gland ACCs warrant further mechanistic investigation.

Distal tracheal resection and reconstruction through right posterolateral thoracotomy

Many retrospective series have been reported on the outcomes of tracheal resection for adenoid cystic carcinoma. However, demonstration on techniques of surgery and ventilatory management during the procedure are rare. We, herewith demonstrate a surgical video, wherein a distal tracheal resection was performed through right posterolateral thoracotomy.

Clinical outcomes and the role of bronchoscopic intervention in patients with primary pulmonary salivary gland-type tumors

OBJECTIVES

Primary pulmonary salivary gland-type tumors (PSGT) are rare among all types of lung cancer. The purpose of this study was not only to evaluate the clinical outcomes and prognostic factors after treatment, but also to assess the role for bronchoscopic intervention in PSGT.

METHODS

We analyzed the medical data of 181 PSGT patients who were treated between 1995 and 2018. Patients were divided into three groups according to the initial treatment, as follows: surgical resection with/without adjuvant therapy including bronchoscopic intervention (surgery group, n = 116); bronchoscopic intervention without surgical resection (bronchoscopic intervention group, n = 51); and other treatments group (n = 14). A multivariable Cox proportional hazard regression analysis was used to identify the independent prognostic factors associated with overall survival (OS) and progression free survival (PFS) after the first treatment. In addition, subgroup analysis was performed according to the clinical stage.

RESULTS

Among the 181 patients, 104 (57.5%) patients were diagnosed with adenoid cystic carcinoma (ACC), 71 (39.2%) with mucoepidermoid carcinoma, and 6 (3.3%) with epithelial-myoepithelial carcinoma. In the surgery group, 21 patients underwent bronchoscopic intervention as a bridge therapy before surgery because of respiratory distress. Poor OS was associated with older age, the existence of other malignancy, higher clinical stages, larger tumor size, and non-surgical treatments. Lower PFS was associated with ACC, larger tumor size, and non-surgical treatments. The surgery group had the best OS and PFS among all treatment groups. However, there was no significant difference in the OS between the surgery and bronchoscopic intervention groups (p = 0.66) in patients at high clinical stages.

CONCLUSIONS

Surgical resection was the best initial treatment choice. However, bronchoscopic intervention may be useful as the initial treatment in patients at high clinical stage and as a bridge therapy prior to surgery.

Challenging tracheal resection anastomosis: Case series

OBJECTIVES

This study was conducted to review our experience in Otorhinolaryngology Department, Mansoura University Hospitals, Egypt, in the last 2 years in the management of high-risk patients who underwent cricotracheal resection due to different pathologies.

METHODS

This case series included nine patients with severe, grade III or IV subglottic / cervical tracheal stenosis. These patients were considered high risk patients due to unusual pathology / etiology of stenosis or associated surgical field morbidity. Four patients had recurrent stenosis after previous unsuccessful cricotracheal resection, three patients had subglottic stenosis due to external neck trauma which compromised the surgical field. One patient had upper tracheal neoplasm, and in 1 patient there was upper tracheal stenosis associated with tracheo-esophageal fistula.

RESULTS

Successful decannulation was achieved in all patients (n = 9) without any reported major intraoperative or postoperative compilations.

CONCLUSION

Cases of subglottic / upper tracheal stenosis due to uncommon pathologies like neoplastic lesions, external neck trauma compromising the surgical field and revision cricotracheal resection, can be successfully managed by cricotracheal resection. However, a highly skilled team, well familiar with these surgeries, is mandatory to achieve an optimum outcome.