Adenoid cystic carcinoma: A study of 19 cases of salivary and extra-salivary tumours diagnosed by fine needle aspiration cytology

Value of cytopathology in the diagnosis of adenoid cystic carcinoma and an analysis of misdiagnoses

BACKGROUND

The diagnosis of adenoid cystic carcinoma (ACC) by cytopathology can be challenging. This study was aimed at testing the effectiveness of this technique and at assessing possible differences in the coincidence rate of fine-needle aspiration cytology(FNAC) and brush exfoliation.

METHODS

The pathology database of Southwest Medical University( Luzhou, China) was searched for patients who had undergone surgery or biopsy for ACC between January 2017 and January 2022 and had preoperative cytopathologic results. Their cytologic and histologic data were then analyzed retrospectively and the coincidence rates of cytopathology in the diagnosis of ACC were calculated.

RESULTS

Compared with histopathology, the total coincidence rate of the cytologic diagnosis of ACC was 76.8%, that of FNAC was 78.9%, and that of brush exfoliation was 55.6%.

CONCLUSION

In the diagnosis of ACC, cytopathology is an effective tool; this is especially true of FNAC, which plays an important role in the diagnosis of ACC. The authors further suggest that it is advisable for diagnosticians to master the cytopathological features of ACC to reduce the possibility of preoperative misdiagnoses.

A Delicate Surgical Resection to Treat a Proximal Pulmonary Adenoid Cystic Carcinoma

Pulmonary adenoid cystic carcinoma (PACC) is an exceedingly rare tumor of low-grade malignancy. Diagnosis is often late, so the tumoral process may be huge at presentation. Surgical resection could be challenging, and the recurrence rate would be greater. We report, hereby, a case of proximal PACC with involvement of the carina in a young male adult, without respiratory distress. Surgical resection was performed through a left pneumonectomy followed by a complex trachea-bronchoplastic procedure. During the operative time, the assisted ventilatory mode was carefully chosen. No adjuvant treatment was needed. Our patient is still under clinicoradiological surveillance and remains disease-free.

Intramedullary spinal cord metastasis from an adenoid cystic carcinoma of the external auditory canal: case report

BACKGROUND AND IMPORTANCE

Intramedullary spinal cord metastases (ISCMs) are rare and no cases of ISCM from an adenoid cystic carcinoma (ACC) of the external auditory canal (EAC) have been reported.

CLINICAL PRESENTATION

We report a 54-year old man complaining backpain and worsening myelopathy. He had an ACC of the EAC resected years prior. A spinal MRI demonstrated a contrast-enhancing intramedullary lesion within the conus medullaris. The histopathological diagnosis of the patient was consistent with the patient's primary cancer. At 3 months follow-up, the neurological condition of the patient was unchanged.

CONCLUSIONS

This is the first reported case of ISCM from a primary ACC of the EAC.

Adenoid cystic carcinoma cytology: Salivary gland and nonsalivary gland

OBJECTIVES

Adenoid cystic carcinoma (ACCA) is an uncommon primary malignancy of salivary glands and rarely nonsalivary tissue. This study aims to evaluate the diagnostic accuracy of ACCA on fine needle aspiration (FNA) material and the associated challenges.

METHODS

A search on electronic pathology database from 2006 to 2016 at The Johns Hopkins Hospital found 83 cytology specimens diagnosed as ACCA, 49 with histology follow-up.

RESULTS

Fifty-two females and 31 males were found ranging from 37 to 95 years old (mean 62.5). The tumor size was 1 to 11.5 cm (mean 3.4). FNAs were performed on 46 salivary glands (54.88%), 12 head and neck masses (14.45%), 9 lymph nodes (10.84%), 9 tracheas/lungs (10.84%), 4 vaginal/perineum/gluteal masses (4.82%), and one for each kidney, liver and abdominal/pelvic mass (1.21%). 83 FNA diagnoses revealed 3 nondiagnostics (3.61%), 20 neoplasms with unspecified features (24.10%), 30 basaloid neoplasms (36.14%), 18 ACCA (21.69%), and 12 other malignancies (14.46%). The accuracy of FNA in diagnosis of ACCA comparing to histologic follow-up in 49 cases was 87.5% sensitivity, 66.67% specificity, with 92.11% positive predictive value and 54.55% negative predictive value. The most common mimicker was pleomorphic adenoma.

CONCLUSION

ACCA can be diagnosed not only in the salivary gland FNAs, but also respiratory tract, intra-abdominal, kidney, and gynecologic regions. FNA is a preferred technique to assess mass lesions. However, a diagnosis of ACCA on FNA material should be rendered with caution since there are benign and malignant neoplasms with overlapping features. Awareness of prior medical history and ancillary studies can improve the diagnosis.

The Utility of MYB Immunohistochemistry (IHC) in Fine Needle Aspiration (FNA) Diagnosis of Adenoid Cystic Carcinoma (AdCC)

Differentiating adenoid cystic carcinoma (AdCC) from other basaloid neoplasm in a fine needle aspiration (FNA) sample can be challenging. Activation of MYB in AdCC by the fusion transcript MYB-NFIB has been recently demonstrated in salivary gland and other organs. The aim of this study is to evaluate the utility of MYB immunohistochemistry (IHC) in distinguishing AdCCs and other basaloid neoplasm in cytology specimens. Eighteen FNA cases, from salivary gland and other sites, and their subsequent surgical resection specimens were included in the study. Eight cases were confirmed AdCC on resection. MYB IHC was performed on slides made from cytology cell block and surgical resection paraffin blocks. Percentage and intensity of nuclear staining in tumor cells was scored as 0 to 3. The staining results were concordant between cytology specimens and their corresponding surgical resection tumors. Strong diffuse nuclear staining (score 3, N = 5) was exclusively observed in AdCC, both in cytology and surgical specimens. Only one pleomorphic adenoma and one poorly differentiated basaloid carcinoma were positive for MYB staining (score 1 to 2). Any degree of nuclear MYB labeling was seen in 100% AdCC cases (N = 8/8) compared with of 20% (N = 2/10) of all other non-AdCC cases (P = < 0.001). The sensitivity and specificity of any degree MYB positivity for AdCC in cytology specimen is 100% and 78%. The sensitivity and specificity of strong diffuse MYB labeling (score 2 to 3) for AdCC is 83% and 100% in cytology specimen. Strong diffuse nuclear staining of MYB is valuable in supporting a cytologic diagnosis of AdCC. However, weak and focal labeling of MYB should be interpreted with caution as it can be seen in benign and other malignant basaloid lesions.

Fine-needle aspiration cytology for the diagnosis of solid basaloid adenoid cystic carcinoma of the breast: Its role, limitation, and perspective

Solid basaloid adenoid cystic carcinoma (SB-AdCC) is a subtype of breast AdCC which shows more aggressive clinical behavior than other subtypes. Fine-needle aspiration (FNA) cytology is a useful diagnostic tool for breast malignancies. However, most of the diagnostic cytological characteristics of AdCC are not present in SB-AdCC and cytomorphological studies of this subtype are limited. Here, we evaluated the utility of FNA in the diagnosis of SB-AdCC of the breast. A search of the pathology archives of our institutions for FNA specimens of histologically confirmed SB-AdCC between 2012 and 2019 identified four patients with SB-AdCC of the breast. All patients were female and the average age was 60 years. Cytologically, one case was classified as malignant, two as indeterminate, and one as unsatisfactory. Smears had low to moderate cellularity. All smears showed ribbon-like material surrounding the clusters and a vertical nuclear arrangement toward the peripheral rim. Hyaline globules appeared only in one case. Cells in all cases showed an oval, angular, and spindle shape hyperchromatic nuclei with mild to severe atypia, and also dispersed naked nuclei similar to the cells of the clusters were detected in one case. In histological sections, these cytological findings were compatible with the histological findings and divergent histological differentiation was detected. Diagnosing of few cellular smears of SB-AdCC is difficult whereas the features of peripheral rim of the clusters, naked nuclei, and the divergent differentiation may be important for diagnosing SB-AdCC of the breast.

Tracheal Adenoid Cystic Carcinoma Presented with Chronic Asthma Diagnosed by Bronchial Washing Cytology

Adenoid cystic carcinoma is a tumor that mainly arises from salivary glands and is present rarely in airways with nonspecific symptoms. Diagnosis based on bronchial washing cytology is rarely reported because this tumor is usually lined by normal mucosa. A 35-year-old woman was referred to our center as a case of unresponsive asthma and hemoptysis for the past year. CT scan showed tracheal mass. Bronchoscopy was done followed by bronchial washing cytology and biopsy. Cytology smears revealed sheets and three-dimensional clusters of small cells, and some of them arranged around hyaline mucoid globules. Cell block and biopsy showed classic pathological findings of adenoid cystic carcinoma. Adenoid cystic carcinoma of the airways can be manifested with nonspecific symptoms and should be considered in the differential diagnosis of airway diseases and asthma. This tumor is rarely seen in the bronchial washing specimen. Characteristic cytological findings and using cell block preparation differentiate adenoid cystic carcinoma from other tumors.

Fine-needle aspiration cytology of extra-salivary adenoid cystic carcinoma

INTRODUCTION

Adenoid cystic carcinoma (ACC) is a ubiquitous tumour which can occur in several sites of the human body. Commonly, it affects the salivary glands but also can rarely occur in various extra-salivary locations.

AIM

To study the clinical and cytological features of extra-salivary ACC on fine needle aspiration cytology.

METHODS

In this paper, we included 27 patients with extra-salivary ACC on fine needle aspiration cytology over a period of 5.5 years. The complete cytomorphological spectrum of extra-salivary ACC was studied.

RESULTS

The mean age of the patients was 50.2 years, with age ranging between 14 and 80 years. Male to female ratio was 1:1.7 with 17 females and 10 males. The most frequent primary site was the orbit, and the most frequent sites of metastasis were liver and lung.

CONCLUSION

Cytopathologists should be alert about the full range of location as well as the cytological spectrum of extra-salivary ACC for greater precision in diagnosis and prompt treatment.

Adenoid Cystic Carcinoma of the Trachea: A Case Report

Patient: Male, 62

Final Diagnosis: Adenoid cystic carcinoma of trachea

Symptoms: Cough • dyspnea

Medication: —

Clinical Procedure: —

Specialty: Surgery