Acinic cell carcinoma (AciCC) is a common salivary gland malignancy, typically composed of neoplastic acinic cells with zymogen granules. The vast majority of cases are driven by a t(4;9)(q13;q31) leading to enhancer hijacking and upregulation of the NR4A3 gene. However, a minority of cases do not display NR4A3 overexpression on immunohistochemical examination and are negative for the rearrangement involving the NR4A3 gene when tested by FISH. Such cases overexpress NR4A2, and the protein product is detectable by immunohistochemistry. In this study, we aimed to assess the utility of NR4A2 and NR4A3 immunohistochemistry in the differential diagnosis of salivary gland tumors. Eighty-five cases of classic low-grade ACiCC, as well as 36 cases with high-grade transformation (HGT) and 7 high-grade AciCC cases were included in the analysis. NR4A3 was at least focally positive in 105/128 (82%) cases. Out of the 23 cases that were immunohistochemically negative for NR4A3, 6 displayed nuclear immunopositivity with the NR4A2 antibody. The NR4A3 rearrangement was confirmed by FISH in 38/52 (73%) cases. In addition, this is the first report of an NR4A2 rearrangement being detected by FISH in 2 AciCC cases that were negative for the NR4A3 rearrangement. Our analysis confirms that the majority of AciCC, including high-grade cases and cases with HGT, are immunopositive for NR4A3, and suggests that NR4A3 immunohistochemistry is a powerful tool in the differential diagnosis of salivary gland tumors. However, its utility is limited in sub-optimally fixed samples which often display weaker and focal positivity. Our study also indicates that in a minority of cases, AciCC might be negative for NR4A3 immunostaining, because the pathogenic genetic event in these cases is instead a rearrangement involving the NR4A2 gene.
- MeSH
- acinární karcinom * diagnóza genetika metabolismus MeSH
- buněčné jádro patologie MeSH
- DNA vazebné proteiny metabolismus MeSH
- imunohistochemie MeSH
- jaderné receptory - podrodina 4, skupina A, člen 2 metabolismus MeSH
- lidé MeSH
- nádorové biomarkery analýza MeSH
- nádory slinných žláz * diagnóza genetika patologie MeSH
- receptory thyreoidních hormonů metabolismus MeSH
- slinné žlázy patologie MeSH
- steroidní receptory * genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
This is a review of the clinical and histopathological published data on very rare heterotopic acinic cell carcinomas (AcCCs) with suggested optimal management. Extrasalivary AcCCs originate primarily in parotid lymph nodes. They present at low clinical stage, show mostly low-grade histopathology and are circumscribed with a complete nodal capsule. Extracapsular dissection was advocated as adequate therapy. In rare cases with positive surgical margins, a completion parotidectomy or adjuvant radiotherapy should follow. Heterotopic high-grade AcCCs are rare, necessitating radical surgery including neck dissection and adjuvant radiotherapy. The short term prognosis is excellent, long term outcomes are not known. Longer term follow-up is essential.
AIMS: Secretory carcinoma (SC) (synonym: mammary analogue secretory carcinoma) is a low-grade salivary gland tumour that occurs in both major and minor salivary glands. SC is known for its wide morphological, architectural and immunohistochemical spectrum, which overlaps with those of several salivary gland neoplasms, including acinic cell carcinoma (AciCC) and intercalated duct-type intraductal carcinoma (IDC) in major salivary glands, and polymorphous adenocarcinoma (PAC) in minor salivary glands. These tumours share with SC some morphological features and SOX10 immunoreactivity; also, with the exception of AciCC, they all coexpress S100 and mammaglobin. METHODS AND RESULTS: We compared MUC4 and mammaglobin expression in 125 salivary gland carcinomas (54 genetically confirmed SCs, 20 AciCCs, 21 PACs, and 30 IDCs) to evaluate the potential of these two markers to differentiate these entities. Moderate to strong diffuse MUC4 positivity was detected in 49 SCs (90.7%), as compared with none of the IDCs and PACs. In contrast, mammaglobin was frequently expressed in SCs (30 of 36 cases; 83.3%), IDCs (24/28; 85.7%), and PACs (7/19; 36.8%). Two of three high-grade SCs lost MUC4 expression in the high-grade tumour component. No significant correlation was found between MUC4 expression and the fusion variant in SC (ETV6-NTRK versus non-ETV6-NTRK). CONCLUSION: The results of our study identify MUC4 as a sensitive (90.7%) and specific (100%) marker for SC, with high positive (100%) and negative (93.4%) predictive values. Thus, MUC4 may be used as a surrogate for SC in limited biopsy material and in cases with equivocal morphology.
- MeSH
- acinární karcinom diagnóza patologie MeSH
- diferenciální diagnóza * MeSH
- karcinom diagnóza patologie MeSH
- lidé MeSH
- mammaglobin A metabolismus MeSH
- mucin 4 analýza MeSH
- nádorové biomarkery analýza MeSH
- nádory slinných žláz * diagnóza metabolismus patologie MeSH
- sekreční karcinom mamárního typu diagnóza metabolismus patologie MeSH
- slinné žlázy patologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Recently, we discovered the recurrent genomic rearrangement [t(4;9)(q13;q31)] enabling upregulation of the transcription factor Nuclear Receptor Subfamily 4 Group A Member 3 (NR4A3) through enhancer hijacking as the oncogenic driver event in acinic cell carcinoma (AciCC) of the salivary glands. In the current study, we evaluated the usefulness of NR4A3 immunostaining and NR4A3 fluorescence in situ hybridization (FISH) in the differential diagnosis of AciCC, comparing a total of 64 AciCCs including 17% cases with high-grade transformation, 29 secretory (mammary analog) carcinomas (MASC), and 70 other salivary gland carcinomas. Nuclear NR4A3 immunostaining was a highly specific (100%) and sensitive (98%) marker for AciCC with only 1 negative case, whereas NR4A3 FISH was less sensitive (84%). None of the MASCs or other salivary gland carcinomas displayed any nuclear NR4A3 immunostaining. The recently described HTN3-MSANTD3 gene fusion was observed in 4 of 49 (8%) evaluable AciCCs, all with nuclear NR4A3 immunostaining. In summary, NR4A3 immunostaining is a highly specific and sensitive marker for AciCC, which may be especially valuable in cases with high-grade transformation and in "zymogen granule"-poor examples within the differential diagnostic spectrum of AciCC and MASC.
- MeSH
- acinární karcinom diagnóza MeSH
- diferenciální diagnóza MeSH
- DNA vazebné proteiny analýza biosyntéza MeSH
- dospělí MeSH
- imunohistochemie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- nádorové biomarkery analýza MeSH
- nádory slinných žláz diagnóza MeSH
- receptory thyreoidních hormonů analýza biosyntéza MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- senzitivita a specificita MeSH
- steroidní receptory analýza biosyntéza MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Mammary analogue secretory carcinoma of salivary gland origin (MASC) is a recently described tumor with ETV6 translocation. Akin to secretory breast cancer, MASC expresses S-100 protein, mammaglobin, vimentin, and harbors a t(12;15) (p13;q25) translocation which leads to ETV6-NTRK3 fusion product. Histologically, MASC displays a lobulated growth pattern and is often composed of microcystic, tubular, and solid structures with abundant eosinophilic homogeneous or bubbly secretions. Colloid-like secretory material stains positive for periodic acid-Schiff (PAS) with and without diastase and for Alcian blue. The cells of MASC are devoid of PAS-positive secretory zymogen granules. These features help to exclude the most important differential diagnostic considerations, namely acinic cell carcinoma, low-grade cribriform cystadenocarcinoma, cystadenocarcinoma (not otherwise specified), and low-grade mucoepidermoid carcinoma. To date the presence of the ETV6-NTRK3 fusion gene has not been demonstrated in any other salivary gland tumor than MASC. It is likely that MASC is more common than currently recognized and with further studies, the clinical need for molecular studies of the ETV6-NTRK3 fusion may diminish. However, molecular testing is recommended at this time to arrive at the diagnosis of MASC.
- MeSH
- acinární karcinom diagnóza MeSH
- cystadenokarcinom diagnóza MeSH
- diferenciální diagnóza MeSH
- fúzní onkogenní proteiny genetika MeSH
- imunohistochemie MeSH
- karcinom genetika MeSH
- lidé MeSH
- mukoepidermoidní karcinom diagnóza MeSH
- nádorové biomarkery analýza MeSH
- nádory prsu genetika MeSH
- nádory slinných žláz diagnóza genetika MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
