Imaging of Malignant Minor Salivary Gland Tumors of the Head and Neck

Prognostic factors for development of distant metastases in surgically treated high-grade salivary gland carcinomas: results of retrospective single center study with 213 patients

PURPOSE

Distant metastases (DM) are the primary cause of treatment failure and death of patients with salivary gland carcinomas (SGC). The purpose of present study was to evaluate factors predictive on DM development in a cohort of patients with high-grade salivary gland carcinomas.

METHODS

This was a retrospective cohort study of consecutive patients surgically treated with curative intention at the authors' institution from January 1993 to December 2018. Outcomes evaluated were overall survival (OS), disease specific survival (DSS), recurrence free survival (RFS), locoregional recurrence free survival (LRFS) and distant metastasis free survival (DMFS).

RESULTS

A total of 213 patients, 117 males (55%) and 96 females (45%), were included in the study. Parotid gland malignancies accounted for 56% of all cases. Adenoid cystic carcinoma (119 cases; 56%) was the most common tumor type. Cumulative OS for the 5-and 10-year follow-up period was 80% and 58% respectively. DM occurred with 75 patients (35%). The most common locations for DM were lung (55 cases; 73%) and liver (12 cases; 16%). Pathological nodal status, particularly the number of metastatic nodes, was the independent prognostic factor for OS, DSS, RFS and DMFS.

CONCLUSION

Number of metastatic lymph nodes, instead of extranodal extension and largest nodal diameter, was the contributing factor related to DMFS. Since the main function of staging system is to predict outcomes, the significance of extranodal extension and nodal dimension in salivary gland cancer staging system requires further clarification. The elective neck dissection could be considered therapeutic approach for high-grade SGC since occult metastases were detected in 33% of cases.

Imaging of the Sinonasal Cavities

This article describes the various abnormalities that affect the sinonasal cavities and discusses inflammations, tumors, and tumor-like conditions. Specific imaging evaluations that focus on the sinonasal cavities are described in more detail.

Primary Pathology of the Parapharyngeal Space

The radiologically defined parapharyngeal space is a distinct location on cross-sectional imaging and is often described based on its displacement or invasion by tumors or other pathologies in adjacent spaces; however, there are multiple primary pathologic entities of the parapharyngeal space, which are often forgotten. Recognizing that a lesion is arising from the parapharyngeal space is important in generating an accurate differential diagnosis that will guide management.

EWSR1 rearranged primary renal myoepithelial carcinoma: a diagnostic conundrum

Primary renal myoepithelial carcinoma is an exceedingly rare neoplasm with an aggressive phenotype and Ewing sarcoma breakpoint region 1 (EWSR1) rearrangement in a small fraction of cases. In addition to its rarity, the diagnosis can be challenging for the pathologist due to morphologic heterogeneity, particularly on the biopsy specimen. At times, immunohistochemistry may be indecisive; therefore, molecular studies should be undertaken for clinching the diagnosis. We aim to illustrate a case of primary myoepithelial carcinoma of the kidney with EWSR1-rearrangement in a 67-year-old male patient who presented with right supraclavicular mass, which was clinically diagnosed as carcinoma of an unknown primary. An elaborate immunohistochemical work-up aided by fluorescent in-situ hybridization allowed us to reach a conclusive diagnosis. This unusual case report advocates that one should be aware of the histological mimickers and begin with broad differential diagnoses alongside sporadic ones and then narrow them down with appropriate ancillary studies.

Pleomorphic Adenoma of the Palate With an Atypical Malignant Presentation: A Case Report

A pleomorphic adenoma is a mixed salivary gland tumor. The parotid gland is the most common site. The intraoral palate is the most common site due to the abundance of accessory salivary glands in the palatal area. It has a very slow growth rate and is usually painless. Consequently, patients often have a lengthy history of presentation. Herein, we report a case of pleomorphic adenoma of the palate in a 53-year-old male patient. The mass was 5 cm by 4 cm in size. The growth rate was rapid, and it attained a large size in just nine months. On clinical examination, the overlying mucosa was ulcerated. On general examination, lymphadenopathy of the right side level 1 b lymph node was found. These clinical findings were consistent with malignancy. However, the histopathological report negated the clinical findings of malignant salivary gland tumors. The tumor was managed with a wide local excision of the tumor with a 1 cm clear margin. The postoperative course was uneventful. No recurrence was seen after two years of follow-up. A thorough cytological or histological examination is a prerequisite to defining the malignant nature of the lesion.

Minor Salivary Gland Polymorphous Adenocarcinoma With Local Recurrence After Seven Years: A Case Report

Polymorphous adenocarcinoma is a rare neoplasm of the minor salivary glands with an indolent behavior. Here, we report and describe the computed tomography (CT) and magnetic resonance imaging (MRI) of polymorphic adenocarcinoma in a 69-year-old patient who presented with local recurrence seven years after the initial treatment. On contrast CT, the primary lesion appeared heterogeneous and invaded the pterygopalatine fossa and the sphenopalatine foramen. The recurrent lesion on MRI showed a hypointense signal on the T1-weighted sequence, a hyperintense signal on the T2-weighted sequence, and heterogeneous enhancement with contrast. The patient underwent a new surgery for lesion resection and is currently under clinical and radiological follow-up. It is recommended to follow patients for at least 15 years after diagnosis, as local recurrences can occur up to 10 years after the initial treatment.

Malignant and Nonmalignant Lesions of the Oral Cavity

There is a broad spectrum of pathology that occurs in the oral cavity. Knowledge of the different anatomic subsites and contents of each is important for accurate diagnosis and treatment. Oral cavity tumors are predominantly malignant in nature, but there are many nonmalignant lesions of which the practicing clinician should be aware. This article will discuss the anatomy, imaging approaches, and imaging characteristics of nonmalignant and malignant pathology in the oral cavity.

Imaging Approach for Cervical Lymph Node Metastases from Unknown Primary Tumor

Neck swelling due to lymph node (LN) metastasis is one of the initial symptoms of head and neck cancer, and in some cases, the primary tumor is not clinically evident. The purpose of imaging for LN metastasis from an unknown primary site is to identify the primary tumor or detect its absence, which leads to the correct diagnosis and optimal treatment. The authors discuss diagnostic imaging approaches for identifying the primary tumor in cases of unknown primary cervical LN metastases. The distribution and characteristics of LN metastases may help locate the primary site. Unknown primary LN metastasis often occurs at nodal levels II and III, and in recent reports, these were mostly related to human papillomavirus (HPV)-positive squamous cell carcinoma of the oropharynx. Another characteristic imaging finding suggestive of metastasis from HPV-associated oropharyngeal cancer is a cystic change in LN metastases. Other characteristic imaging findings such as calcification may help predict the histologic type and locate the primary site. In cases of LN metastases at nodal levels IV and VB, a primary lesion located outside the head and neck region must also be considered. One clue for detecting the primary lesion at imaging is the disruption of anatomic structures, which can help in identifying small mucosal lesions or submucosal tumors at each subsite. Additionally, fluorine 18 fluorodeoxyglucose PET/CT may help identify a primary tumor. These imaging approaches for identifying primary tumors enable prompt identification of the primary site and assist clinicians in making the correct diagnosis. ^© RSNA, 2023 Quiz questions for this article are available through the Online Learning Center.

Predictive factors for survival and treatment outcomes of patients with minor salivary gland malignancies: a retrospective study

INTRODUCTION

Aim of this study was to explore the incidence, pathology, clinical behaviour and evaluate factors predictive on survival and treatment outcomes in a cohort of patients with minor salivary gland (MiSG) malignancies treated at a single center over a period of 25 years.

MATERIALS AND METHODS

Patients who had received primary treatment for MiSG malignancy during 25 years observation period were identified. Outcomes that were evaluated were overall survival (OS), disease specific survival (DSS), recurrence free survival (RFS), locoregional recurrence free survival (LRFS) and distant metastasis free survival (DFS).

RESULTS

A total of 88 patients with MSG malignancies were included in the study. The most common location for MiSG malignancies was the oral cavity (65 tumors; 77%). Cumulative OS for 5 and 10 year follow up period was 82% and 62% respectively. Cumulative DSS for 5 and 10 year follow up period was 85% and 73% respectively. Twenty one (23%) patients developed distant metastases during follow-up. High-grade pathology and tumor stage were significant variables on multivariate analysis for all survival and treatment outcomes.

CONCLUSIONS

Minor salivary gland malignancies are minor only by name. Tumor histological grade, AJCC tumor stage and pT stage were the strongest predictive factors for survival and treatment outcomes. The elective neck dissection could be considered therapeutic approach for selected cases of high grade MiSG malignancies. Distant metastases were the main cause of death and treatment failure.

Frequency and imaging features of the adjacent osseous changes of salivary gland carcinomas in the head and neck region

PURPOSE

The association between salivary gland carcinomas and adjacent osseous changes in the head and neck region is not clear. We evaluated the frequency and imaging features of such changes and investigated the specific characteristics of salivary gland carcinomas associated with them.

METHODS

A total of 118 patients with histologically proven salivary gland carcinomas were retrospectively reviewed. The imaging characteristics of osseous changes were sorted into three categories based on computed tomography images: sclerotic change, erosive change, and lytic change. The frequency of all these osseous changes and any one of them was compared between different pathologies using Fisher's exact test. Odds ratios were calculated to evaluate the association between these changes and perineural spread.

RESULTS

Osseous changes were found in 21 (18%) of 118 cases. Among these, seven (6%) cases were with sclerotic, nine (8%) with erosive, and nine (8%) with lytic changes (four with mixed change). Adenoid cystic carcinoma showed a significantly higher frequency of sclerotic and erosive changes, and either osseous change, than the other salivary gland carcinomas (p < 0.001 for each). Sclerotic changes were only present in the adenoid cystic carcinomas. Perineural spread was a significant factor in showing higher osseous change frequencies (odds ratio = 3.98, p = 0.006).

CONCLUSION

Among salivary gland carcinomas in the head and neck region, adenoid cystic carcinomas had a significantly higher frequency of adjacent osseous changes, especially sclerotic changes, than other salivary gland carcinomas.

Radiologic Evaluation of the Head and Neck Cancer Patient

CT, PET, ultrasound, and MRI examinations all have roles in the staging and surveillance of cancers in the head and neck. Contrast-enhanced CT is generally the primary examination because of availability, cost, reproducibility, and good overall quality regardless of where performed. PET, ultrasound, and MRI have more specific and nuanced applications. Good interdisciplinary interactions with radiologist consultation can streamline the examination process and reduce the examination burden on patients by limiting the number and maximizing the quality of the examinations and image-guided interventions performed.