Hyalinizing clear-cell carcinoma of salivary glands in fine-needle aspiration

Base of the tongue hyalinizing clear cell carcinoma: Case report and literature review

Hyalinizing clear cell carcinoma is an uncommon neoplasm arising in minor salivary glands. We present a rare case of hyalinizing clear cell carcinoma in the base of the tongue. We report a case of a 38-year-old female presented with a progressive history of hemoptysis and dysphagia over the course of 4 years. Examination revealed a mass originating from the base of the tongue with a biopsy confirmed as hyalinizing clear cell carcinoma . An Ovid MEDLINE and PubMed literature review was conducted due to the rarity of this type of tumor. The patient underwent surgical excision with immediate reconstruction with radial forearm free flap followed with adjuvant radiotherapy and was disease free at her most recent follow-up (12 months). Our review included a total of 13 new cases, including our case. The majority of the cases presented with dysphagia. Surgical excision is the mainstay of treatment, and overall these patients have a good prognosis. Our case highlights a rare presentation of hyalinizing clear cell carcinoma of the base of the tongue, successfully treated with surgical excision, free tissue reconstruction and adjuvant radiotherapy.

A Case of Buccal Clear Cell Carcinoma Caused by Rare Fusion Gene: EWSR1-CREM

Clear cell carcinoma (CCC) is a rare entity in the salivary gland tumor. So far, only 10 cases of primary CCC of the buccal mucosa have been reported. Here, we first report an extremely rare case of buccal CCC with the EWSR1-CREM fusion gene. The patient, a 69-year-old woman, presented with a painless mass in the right buccal mucosa. The tumor, which had been present for about 10 years, measured approximately 15 mm in diameter and was pedunculated, elastic hard, smooth, and mobile. Histopathological examination revealed proliferating tumor cells with vacuolated and clear cytoplasm partially surrounded by hyalinized stroma. The tumor was not encapsulated, and no contact with the overlying epithelium was evident. Duct-like structures were occasionally observed in the tumor nests composed of clear cells. The tumor had invaded into surrounding muscle and adipose tissues. Immunohistochemical examination revealed that the clear cells were positive for epithelial cell markers, and myoepithelial markers were negative. Fluorescence in situ hybridization (FISH), performed to search for genetic abnormalities, demonstrated split positivity for EWSR1, and fusion with CREM was confirmed. These findings suggested a diagnosis of CCC.

Clear cell carcinoma: a comprehensive literature review of 254 cases

This comprehensive literature review represents a summary of all cases of clear cell carcinoma (CCC) of the salivary glands that are documented in the literature. PubMed was used to collect available reports of CCC; 97 reports detailing 254 cases, published between 1983 and 2020, were retrieved. Clinically the tumor manifests most commonly as a painless mass or swelling on the palate, and the duration of symptoms prior to seeking care ranges from 1 week to 6 years. Local tumor recurrence was present in 18.8% of the cases. By histopathology, CCC shows a mixture of growth patterns including solid (25.1%), nested (78.6%), sheet-like (23.5%), cords (46.1%), and trabeculae (42.4%). Immunohistochemical studies are positive for one or more cytokeratins (99.1%), PAS (95.1%), EMA (77.8%), and p63 (96.3%), but negative for S-100 (96.3%), PASD (91.1%), SMA (91.0%), and calponin (95.1%). Molecular features were reported in 113 cases; 96.0% were positive for an EWSR1 rearrangement by EWSR1 break apart FISH testing and 14.8% were positive for the rearrangement EWSR1-ATF1 tested by qPCR or targeted RNA sequencing. Clinical patterns and genetic studies imply that this tumor is the extraosseous counterpart of clear cell odontogenic carcinoma, an intraosseous odontogenic tumor of the jaws.

Integrative sequencing discovers an ATF1-motif enriched molecular signature that differentiates hyalinizing clear cell carcinoma from mucoepidemoid carcinoma

OBJECTIVES

Salivary gland tumors are comprised of a diverse group of malignancies with widely varying prognoses. These cancers can be difficult to differentiate, especially in cases with limited potential for immunohistochemistry (IHC)-based characterization. Here, we sought to define the molecular profile of a rare salivary gland cancer called hyalinizing clear cell carcinoma (HCCC), and identify a molecular gene signature capable of distinguishing between HCCC and the histopathologically similar disease, mucoepidermoid carcinoma (MEC).

MATERIALS AND METHODS

We performed the first integrated full characterization of five independent HCCC cases.

RESULTS

We discovered insulin-like growth factor alterations and aberrant IGF2 and/or IGF1R expression in HCCC tumors, suggesting a potential dependence on this pathway. Further, we identified a 354 gene signature that differentiated HCCC from MEC, and was significantly enriched for genes with an ATF1 binding motif in their promoters, supporting a transcriptional pathogenic mechanism of the characteristic EWSR1-ATF1 fusion found in these tumors. Of the differentially expressed genes, IGF1R, SGK1 and SGK3 were found to be elevated in the HCCCs relative to MECs. Finally, analysis of immune checkpoints and subsequent IHC demonstrated that CXCR4 protein was elevated in several of the HCCC cases.

CONCLUSION

Collectively, our data identify an ATF1-motif enriched gene signature that may have clinical utility for molecular differentiation of HCCCs from other salivary gland tumors and discover potential actionable alterations that may benefit the clinical care of recurrent HCCC patients.

Does Nodal Metastasis and Perineural Invasion Affect Local Control in Hyalinizing Clear Cell Carcinoma of the Oral Cavity? A Case Report with Long Term Follow-Up

Hyalinizing clear cell carcinoma (HCCC) is a rare, low-grade neoplasm accounting for approximately 1% of salivary gland neoplasms. Histologically, it is characterized by a monomorphous population of clear cells arranged in sheets, nests, or cords, lacking ductal structures. Until recently, clear cell carcinoma of the oral cavity (OC) represented a diagnosis of exclusion when other head and neck pathologic entities such as epithelial-myoepithelial carcinoma or mucoepidermoid carcinoma could be ruled out, making definitive diagnosis by light microscopy and immunoprofiling a challenge. As a result, initial biopsies are often misclassified, and could result in under- or overtreatment. More recently, the presence of the EWSR1-ATF1 gene fusion has been adopted to definitively diagnose HCCC. Typically, HCCC demonstrates clinical indolence and responds well to curative surgical excision alone for localized disease, with adjuvant radiotherapy (RT) reserved for high risk features including perineural invasion, lymphovascular invasion, and regional cervical metastasis. The literature, however, lacks consensus regarding the role of adjuvant radiotherapy. In this article, we report a case of HCCC in a rare site involving the ventral tongue, with high risk features of perineural invasion and cervical nodal metastasis. The patient underwent surgical excision alone; declining adjuvant radiotherapy despite the high risk features, and was alive with no evidence of disease at the 42-month mark. Furthermore, we provide an update on the current prognostic indicators for HCCC, and emphasize the need for chromosomal analysis to achieve a definitive diagnosis.

Ancillary testing in salivary gland cytology: A practical guide

Salivary gland cytology is challenging, and historically the role of ancillary testing has been limited. However, numerous molecular/genetic advances in the understanding of salivary gland neoplasms during the last decade have facilitated the development of many useful diagnostic markers, such as PLAG1 and HMGA2 immunohistochemistry for pleomorphic adenoma and ETV6 fluorescence in situ hybridization for secretory carcinoma. Numerous salivary gland neoplasms are characterized by specific molecular/genetic alterations, many of which can be identified on cytologic preparations by karyotype analysis, fluorescence in situ hybridization, or immunohistochemical surrogates. Next-generation sequencing also has potential diagnostic applications, although to the authors' knowledge it currently has no routine role in salivary cytology. The primary goal of salivary fine-needle aspiration (FNA) is to facilitate appropriate clinical management. Ancillary testing has greatly enhanced the ability for accurate classification as per The Milan System for Reporting Salivary Gland Cytopathology and allows for the definitive diagnosis of many salivary FNA specimens, and also may resolve diagnostic uncertainty for FNAs that may be classified in The Milan System for Reporting Salivary Gland Cytopathology categories of salivary gland neoplasm of uncertain malignant potential or suspicious for malignancy. This review provides an updated discussion of the molecular/genetic features of the more commonly encountered salivary neoplasms by FNA, and discusses the application of available diagnostic immunohistochemical and molecular tests in salivary gland cytology.

The key radiologic and cytomorphologic features of oncocytic and oncocytoid lesions of the salivary gland

Oncocytic and oncocytoid lesions represent a distinct subset of salivary gland lesions. True oncocytic lesions of the salivary gland are entirely composed of oncocytes. These are characterized by the presence of abundant eosinophilic granules due to the presence of abundant cytoplasmic mitochondria. Oncocytic lesions of the salivary gland include oncocytosis, oncocytoma, and oncocytic carcinoma. In addition to the true oncocytic lesion, there exists another group of salivary gland lesions, which demonstrate cells with abundant and occasionally granular cytoplasm. These are often termed as "oncocytoid" lesions. The recently proposed Milan System for reporting salivary gland cytology clearly states that fine-needle aspiration specimens representing oncocytic/oncocytoid lesions of salivary gland cannot effectively distinguish between a nonneoplastic lesion, benign and malignant neoplasms. Therefore, most lesions lacking classic cytomorphologic features will be classified under the umbrella diagnostic term of "Salivary Gland Neoplasm of Uncertain Malignant Potential" (SUMP). In this review, we discuss and illustrate key clinicopathologic and radiologic features that can help the practicing cytopathologist narrow down the differential and provide the best management based diagnosis.

Hyalinizing clear cell carcinoma of salivary glands: A retrospective study focused on uncommon morphology, immunohistochemistry, and detection of gene fusion using fluorescence in situ hybridization

AIMS

To investigate histological, immunohistochemical, and molecular features, especially uncommon morphology of hyalinizing clear cell carcinoma (HCCC) to expand the morphological spectrum of HCCC.

METHODS AND RESULTS

We examined 5 cases of HCCC by histological, immunohistochemical, and molecular analysis. Generally, 5 HCCC cases shared similar characteristics, exhibiting clear to slightly eosinophilic cells arranged in cords, nests, islands, or trabeculae with a hyalinized stroma, while myxoid stroma, perineural invasion, and polygonal cells with high-grade nuclei were observed in 3 cases. Immunohistochemically, 5 cases were entirely immunoreactive for CKpan, whereas 80% HCCC cases were positive for P63, and CK14. None expressed immunoreactivity for S-100, Calponin, or GFAP. The positive rate of Ki-67 staining was about 5% in the classic area of case 3, but 40% in the high-grade area. As for the result of FISH findings, EWSR1 gene break was detected in all 5 HCCC cases.

CONCLUSIONS

Our study has expanded the morphological spectrum of HCCC, and proposed the diagnosis of HCCC should be confirmed by fully analyzing histological, immunohistochemical, and molecular features practically.

Hyalinizing clear cell carcinoma of salivary gland origin in the head and neck: clinical and histopathological analysis

Hyalinizing clear cell carcinoma (HCCC) is an extremely rare neoplasm of salivary gland origin with a low-grade indolent nature. It is difficult to distinguish from other malignant salivary gland tumours. Clinical outcomes following surgery are generally reported as good. The aim of this study was to further determine the features of HCCC. This study was approved by Medical ethics review of affiliated hospital of jiangsu university. Fourteen new cases of HCCC are reported. The clinical and histopathological data of these 14 cases were analysed alongside those of 141 cases identified in a systematic review of the literature (up to 2016). Demographic data, histopathological findings, clinical presentation, primary treatment, and outcomes were extracted. Histologically, HCCC tumour cells had a clear cell morphology with hyalinized stroma. Immunohistochemical results were positive for cytokeratins and EMA, but negative for SMA, S100, vimentin, and calponin. Twelve of the 14 patients showed EWSR1 translocation. Local nodal metastasis on presentation was present in 17.3% and the overall recurrence rate was 17.7% in the total population (N=155), compared with 35.7% and 21.4%, respectively, in the new cases alone. Focal necrosis and local metastasis were identified as possibly associated with recurrence. The overall prognosis was good: only 3.8% of patients died of the disease. HCCC is less indolent than was previously thought, but overall the prognosis is good. Risk factors for recurrence may include focal necrosis and local metastasis at presentation. The best treatment for patients with HCCC is wide local excision combined with regional lymph node dissection.

Very delayed cervical lymph node metastases from hyalinizing clear cell carcinoma: report of 2 cases

BACKGROUND

Hyalinizing clear cell carcinoma (HCCC) is a rare salivary gland neoplasm most often found in the oral cavity. Although it is generally a low-grade malignancy that is treated with wide local excision, there is a growing body of evidence pointing toward the potential for more aggressive behavior.

METHODS

We reviewed available records of patients with delayed cervical lymph node metastases from HCCC.

RESULTS

Two patients who were treated with wide local resection for HCCC and remained disease-free at the primary site were diagnosed with cervical lymph node metastases 10 and 14 years later. We treated both with neck dissection, and 1 patient received adjuvant radiation therapy.

CONCLUSION

These cases illustrate the risk for occult nodal metastases from HCCC with delayed presentation. Clinician awareness of the presence of subclinical metastases in the neck requires thorough long-term surveillance and potential intervention should nodal disease become manifest.

Clear Cell Carcinoma of the Base of the Tongue

Objective:

Clear cell carcinoma (CCC) is a rare, low-grade malignant neoplasm of minor salivary glands. Clear cell carcinoma is composed of monomorphic clear cells that contain glycogen within a hyalinized stroma. The microscopic diagnosis can be challenging, and the treatment strategy has not been established.

Methods:

We report a case of a 56-year-old woman with CCC in the base of the tongue. A literature review, including 22 published cases and our case, was performed to clarify the clinical characteristics of CCC in the base of the tongue.

Results:

The exophytic tumor showed no infiltration to the neighboring tissues. She underwent a local excision en bloc transorally and is free of the disease 15 months after surgery. In our review of 23 cases of CCC in the base of the tongue, 21 cases received surgical excision for the purpose of the primary treatment modality. The fact that the distinctive features of restricted site-related symptoms and the rare presentation of pain emerged was similar to previously reported cases of CCC. A relatively good prognosis was still indicated.

Conclusion:

We reveal the features of the unusual occurrence of CCC in the base of the tongue and consider the appropriate surgical approach for primary treatment.

Hyalinizing clear cell carcinoma: a case report and review of the literature

Hyalinizing clear cell carcinoma (HCCC) is a low-grade malignancy with infiltrative growth pattern. It affects mainly the minor salivary glands of adult women. The most frequent locations of this tumor are the palate and tongue. HCCC shows a poorly circumscribed, infiltrative, and essentially monomorphic population of clear cells with few mitoses and almost no nuclear or cellular pleomorphism. These cells form trabeculae, cords, islands, and/or nests, circumscribed by variable amounts of hyalinized fibrous bands with foci of myxohyaline stroma. S-100 protein, muscle-specific actin, smooth muscle actin, myosin, and calponin are consistently negative, which strongly indicates the absence of myoepithelial cell differentiation in this tumor. We present a case of HCCC affecting the upper vestibule in a 53-year-old man. The patient was treated by surgery and postoperative radiation and did not show recurrence or distant metastases 3 years after treatment. Discussed also are the clinical and pathologic features of this tumor along with the differential diagnosis and a literature review.

Clear cell adenocarcinoma of the base of the tongue: a case report and review of the literature

Clear cell adenocarcinoma is an extremely rare tumor of the head and neck region. We report a case of a 75-year-old Caucasian woman with a 10-day history of hemoptysis but with no pain or other significant symptoms. A head and neck computed tomography scan with contrast medium showed an irregular, soft-tissue-like, irregularly enhanced lesion of the base of the tongue extending to its posterolateral portion. The tumor reached the lateral wall of the oropharynx, which showed a nonhomogeneous aspect. The patient underwent resection of the tumor via a conservative transmandibular approach. A clear cell adenocarcinoma of the base of the tongue is rarely a primary malignant lesion; it is more frequently a secondary lesion from a metastatic renal tumor. Because of this neoplasm's relatively slow growth rate and low incidence of metastasis or local recurrence, the gold standard of treatment is complete excision of the tumor with a sufficient tumor-free margin.

Clear cell carcinoma of the minor salivary gland: an autopsy case with multiple metastases 29 years after the initial surgery and a review of the literature

Clear cell carcinoma of the salivary gland is an uncommon tumor comprising about 1% of neoplasms of minor salivary glands. We report an autopsy case of a tumor with widespread metastases 29 years after initial surgery. At the initial presentation, the patient was a 48-year-old man with a small ulcerative tumor in the right hard palate, and the tumor was excised. Twenty-four years after the initial excision, the first recurrence was detected in the lung. Five years later, the patient died of widespread metastases of the disease at the age of 77. Specimens obtained at the initial excision and at autopsy were very similar histologically and immunohistochemically, and both were clear cell carcinoma of the salivary gland. The patient died of the disease after a very long disease-free period, which reinforces the classification of this tumor as a low-grade malignancy.

Hyalinizing clear cell carcinoma: report of eight cases and a review of literature

Hyalinizing clear cell carcinoma (HCCC) is an extremely rare neoplasm with a female predominance, composed of nests of monomorphic clear cells within a hyaline stroma. This tumor often follows an indolent course and treatment includes wide surgical excision with or without adjuvant radiotherapy. We report eight cases of HCCC identified at two academic institutions in six women and two men, ranging in age from 25 to 86 years. Histologically, all cases demonstrated cords, trabeculae, and nests of monomorphic clear cells as well as cells with eosinophilic granular cytoplasm. Mild cellular atypia was occasionally seen and mitoses were very rare. Seven cases demonstrated a hyalinized stroma, and one case, a myxoid stroma. Immunohistochemically, the tumor cells were positive for epithelial markers and negative for desmin and actin. Seven cases were negative for S-100. Cells were also positive for periodic acid-Schiff and negative for mucin. The important clinicopathologic features and the differential diagnoses of HCCC, as well as a review of the literature are discussed.

Hyalinizing clear cell carcinoma: case series and comprehensive review of the literature

BACKGROUND

Hyalinizing clear cell carcinoma (HCCC) is an uncommon malignant salivary gland tumor that was characterized only recently as a distinct entity. Because of its histologic similarity to several other primary and metastatic tumors and its purported favorable clinical outcome after local resection, it is important to recognize the features of this unusual tumor.

METHODS

The authors present 8 new, fully characterized cases of HCCC and systematically reviewed 44 other cases of HCCC reported in the English language literature from 1980 to 2008. Historic cases were reviewed, and available data regarding morphology, special stains, demographics, clinical presentation, radiographic findings, management, and outcomes were extracted. Data from the current series were compared with the earlier published literature.

RESULTS

To the best of the authors' knowledge, this was the largest reviewed series of HCCC and included a total of 52 cases. The findings, which included key histologic features, clinical presentation, and outcome, generally were consistent with what was reported previously. However, the current review revealed that 25% of patients reported in the literature had metastatases at initial presentation, including 10 of 44 patients who had metastases to regional lymph nodes and 1 patient who had metastasis to the lung. The authors were unable to identify any specific histologic features that would predict this behavior.

CONCLUSIONS

The current results indicated that HCCC is less indolent than was believed previously; therefore, regional lymph node dissection should be considered in conjunction with wide local excision for patients with HCC.

Clear cell carcinoma, not otherwise specified, of salivary glands: a clinicopathologic study of 4 cases and review of the literature

Clear cell carcinoma, not otherwise specified (CCC-NOS), is a recently described rare malignant salivary neoplasm. We report the clinicopathologic and immunohistochemical features of 4 cases. The results were then analyzed collectively with the approximate 60 cases of CCC-NOS reported in the English-language literature to define the characteristics of this unusual neoplasm. Combining our cases with those in the literature, a total of 66 cases, confirms that CCC-NOS is a low-grade malignant neoplasm with distinctive clinical and pathologic features. It arises primarily in the minor salivary glands (91% of cases), particularly in the palate or base of tongue, and usually occurs in patients >30 years of age (mean 54.2 years) with a female-to-male ratio of 1.4:1; 12.3% of patients experience local recurrences, 19.3% develop positive regional lymph nodes, 8.8% have distant metastases, and 3.5% die of the disease. Immunohistochemical study focusing on tumor differentiation was performed for our cases, and the findings support the concept that CCC-NOS is of ductal epithelial origin without myoepithelial cell participation.

Hyalinizing clear cell carcinoma of salivary gland: an aggressive variant

Although hyalinizing clear cell carcinoma (HCCC) had been previously illustrated by several authors, it was not until 1994 that this tumour was characterized by Milchgrub et al. [Am J Surg Pathol (1994),18,74] and separated from the heterogeneous group of clear cell carcinomas described in the literature. HCCC is a distinctive infiltrative low-grade, monomorphic, glycogen-rich clear cell carcinoma with prominent stromal hyalinization occurring most often in the minor salivary glands of adult women. A case of hyalinizing clear cell carcinoma arising in the tongue of an adult female is described with special reference to the presence of minor foci of mitotic activity, necrosis and anaplasia in this otherwise typical low-grade carcinoma. Widespread metastases and death within a year of initial presentation in this case suggests that there may be a subset of this indolent tumour in which these features are associated with a poor prognosis.