Salivary Duct Carcinoma: An Update on Morphologic Mimics and Diagnostic Use of Androgen Receptor Immunohistochemistry

TRPS1 expression in cytologic specimens of salivary duct carcinoma and other salivary gland tumors

Recent studies suggest that trichorhinophalangeal syndrome type 1 (TRPS1) is sensitive immunomarker for breast carcinoma (BC). Salivary duct carcinoma (SDC) of salivary gland can share similar morphologic and immunophenotypic features with BC. This study aimed to assess the expression of TRPS1 in SDC and other salivary gland tumors (SGTs). Cytology cases and selected surgical specimens of SGTs were retrieved. Forty-three cases were selected and TRPS1 immunohistochemistry (IHC) was performed on cell blocks and some histologic specimens. Of those 43 cases, all 13 SDC cases showed TRPS1 expression except for one case. The remaining 30 cases include pleomorphic adenoma (n = 7), Warthin tumor (n = 4), basal cell adenoma (n = 3), adenoid cystic carcinoma (n = 2), secretory carcinoma (n = 5), mucoepidermoid carcinoma (n = 4), and acinic cell carcinoma (n = 5). Three of thirty cases were negative for TRPS1 while the remainder showed variable expression of TRPS1 ranging from focal weak to diffuse strong staining. The three negative cases include a case of secretory carcinoma, mucoepidermoid carcinoma and Warthin tumor. Our study confirmed that TRPS1 expression is present in SDC and other SGTs, indicating an overlapping immunoprofile with breast cancer. Additionally, it may not help differentiate SDC or SGTs from each other. Further studies with larger cohorts are needed.

High-grade salivary carcinomas: A current insight on diagnostic pathology and the key to clinical decision making

High-grade carcinomas of the salivary glands are a group of several tumor entities with highly malignant histologic appearances, and have an aggressive biological behavior accompanied by poor a prognosis. In general, they require more intensive treatment than low- or intermediate-grade carcinomas. High-grade salivary carcinomas are rare and the microscopic features often overlap between different tumor types, making an appropriate diagnosis challenging in daily practice settings. However, with recent rapid advances in molecular pathology and molecular-targeted therapy in this field, there is a growing need to properly classify tumors, rather than just diagnosing the cases as "high-grade carcinomas". This leads to specific treatment strategies. In this article, we review representative high-grade salivary gland carcinomas, including salivary duct carcinoma and its histologic subtypes, high-grade mucoepidermoid carcinoma, solid-type adenoid cystic carcinoma, and high-grade transformation of low- or intermediate-grade carcinomas, and discuss their differential diagnoses and clinical implications. Other rare entities, such as neuroendocrine carcinoma, NUT carcinoma, and metastatic carcinoma, should also be considered before diagnosing high-grade carcinoma, NOS. Of these tumors, salivary duct carcinoma has received the most attention because of its strong association with androgen deprivation and anti-HER2 therapies. Other tumor-type-specific treatments include anti-TRK therapy for high-grade transformation of secretory carcinoma, but further therapeutic options are expected to be developed in the future. It should be emphasized that detailed histological evaluation with adequate sampling, in addition to the effective use of molecular ancillary tests, is of the utmost importance for a suitable diagnosis.

Acinic cell Carcinoma with high-grade Squamoglandular and Chondrosarcomatous Transformation Mimicking 'Carcinosarcoma ex-pleomorphic Adenoma': A Wrinkle in the Proposed Nomenclature Revision for Sarcomatoid Salivary Gland Neoplasms

While acinic cell carcinoma (AciCC) can undergo high-grade transformation (HGT) to high-grade adenocarcinoma or poorly differentiated carcinoma, other morphologies such as spindle cell/sarcomatoid carcinoma are rare and not well-characterized. We herein report a novel case of AciCC with squamoglandular and chondrosarcomatous HGT mimicking a so-called 'carcinosarcoma ex-pleomorphic adenoma'. The patient is an 81-year-old male with a two-month history of neck swelling and referred otalgia who presented with a left parapharyngeal space mass extending into retropharyngeal space and pterygoid muscles. On resection, the tumor showed considerable morphologic diversity with high-grade serous and mucous acinar components as well as cribriform to solid apocrine-like components with comedonecrosis and squamous differentiation, all of which were embedded in a chondromyxoid background ranging from paucicellular and bland to a high-grade chondrosarcoma/pleomorphic sarcoma-like appearance. Only a minor conventional AciCC component was noted. Immunostains were negative for AR and only focally positive for GCDFP-15 arguing against a true apocrine phenotype, while PLAG1 and HMGA2 were negative arguing against an antecedent pleomorphic adenoma. On the other hand, SOX-10, DOG-1 and PAS after diastase highlighted serous acinar differentiation, and mucicarmine, and NKX3.1 highlighted mucous acinar differentiation. NR4A3 immunohistochemical staining and NR4A3 fluorescence in situ hybridization were positive in the carcinomatous and sarcomatoid components while sequencing analysis of both components revealed identical alterations involving TP53, PIK3CB, ARID1A, and STK11. This unique case warrants caution in designating all salivary sarcomatoid carcinomas with heterologous elements as part of the 'carcinoma ex-pleomorphic adenoma' family.

Gastric Metastasis from Salivary Duct Carcinoma Mimicking Scirrhous Gastric Cancer

A 59-year-old man underwent submandibular gland excision for salivary duct carcinoma (SDC). One year later, esophagogastroduodenoscopy indicated gastric diffuse mucosal thickening with luminal contraction, mimicking scirrhous gastric carcinoma. Biopsy specimens showed dense proliferation of neoplastic cells expressing androgen receptor and human epidermal growth factor 2, indicating SDC. Gastric diffuse infiltrative metastasis is generally characteristic of gastric metastasis from invasive ductal carcinoma, which shows histologic features similar to SDC. This is the first known report of gastric diffusely infiltrating metastasis in an SDC patient. Rapidly progressing, diffuse gastric wall thickening should also be considered indicative of salivary tumor-associated gastric metastasis.

The poor prognosis of lacrimal gland adenocarcinoma: a clinical study and literature review

PURPOSE

The incidence of lacrimal gland adenocarcinoma is low. This study was designed to analyze the clinical and prognostic characteristics of lacrimal gland adenocarcinoma.

METHODS

This was a clinical study and literature review; 25 patients diagnosed with lacrimal gland adenocarcinoma by histopathology were enrolled and their medical history data were collected.

RESULTS

The incidence of bone destruction and surrounding tissue invasion was 52% and 44%, respectively. The incidence of distant metastasis of lacrimal gland adenocarcinoma was about 50%. The 5-year overall survival rate of death or metastasis was 33.5%. Age, sex, laterality, tumor size, pathology type, bone destruction, nerve or perineural invasion, invasion of peripheral tissue, T stage, AR, Her-2 and treatment had no significant correlation with lacrimal adenocarcinoma's prognosis (P > 0.05), while the higher expression of Ki-67 may have higher risk of death or metastasis (P = 0.020).

CONCLUSION

The incidence of bone destruction and distant metastasis of lacrimal adenocarcinoma is high and the imaging examination is necessary to assess the risk of distant metastasis. The 5-year survival rate of death or metastasis is 33.5% and the high expression of Ki-67 predicts poor prognosis of lacrimal adenocarcinoma.

Recent developments in the pathology of primary pulmonary salivary gland-type tumours

Primary pulmonary salivary gland-type tumours are rare neoplasms that are thought to arise from seromucinous glands that are located in the submucosa of large airways. These neoplasms have clinical and pathologic features that are distinct from other pulmonary neoplasms. The majority of primary pulmonary salivary gland-type tumours are malignant, with the most common entities being mucoepidermoid carcinoma, adenoid cystic carcinoma, and epithelial-myoepithelial carcinoma. Less commonly seen are myoepithelial carcinoma, hyalinizing clear cell carcinoma, acinic cell carcinoma, secretory carcinoma, salivary duct carcinoma, intraductal carcinoma, and polymorphous adenocarcinoma. Benign salivary gland-type tumours of the lung include pleomorphic adenoma and sialadenoma papilliferum. Morphologic, immunophenotypic, and molecular features of these neoplasms are largely similar to salivary gland tumours elsewhere, and therefore the exclusion of metastatic disease requires clinical and radiologic correlation. However, the differential diagnostic considerations are different in the lung. The distinction of salivary gland-type tumours from their histologic mimics is important for both prognostication and treatment decisions. Overall, salivary gland type-tumours tend to have a more favourable outcome than other pulmonary carcinomas, although high-grade variants exist for many of these tumour types. Recent advances in our understanding of the spectrum of salivary gland-type tumours reported in the lung and their diversity of molecular and immunohistochemical features have helped to refine the classification of these tumours and have highlighted a few differences between salivary gland-type tumours of the lung and those primary to other sites.

Salivary Duct Carcinoma Originated from the Inferior Turbinate: A Rare Case Report

Salivary duct carcinoma (SDC) is an uncommon but highly aggressive tumor with a poor prognosis. SDC mainly arises from the major salivary glands, typically the parotid gland. Here, we report a rare case of sinonasal SDC in a 54-year-old male patient that might have originated from the inferior turbinate. The patient presented with left nasal congestion and rhinorrhea. Following an endoscopic intervention, the histopathological examination revealed a diagnosis of SDC, characterized by the formation of solid cancer nests and central comedo-type necrosis. Given the highly aggressive nature and unfavorable prognosis of SDC, it is essential to consider it as a differential diagnosis for unilateral nasal tumors.

Mucoepidermoid carcinoma may be devoid of squamoid cells by immunohistochemistry: expanding the histologic and immunohistochemical spectrum of MAML2- rearranged salivary gland tumours

Mucoepidermoid carcinoma (MEC) is historically defined by a mix of squamoid, intermediate, and mucous cells, but we have recently encountered several cases lacking immunoreactivity for squamous markers p40, p63, and CK5/6 despite MAML2 fusions. This study will characterise these unique tumours. Ten MEC were collected arising from the parotid gland (n = 4), submandibular gland (n = 2), nasopharynx (n = 1), base of tongue (n = 1), bronchus (n = 1), and trachea (n = 1). Six tumours were low-grade, two intermediate-grade, one high-grade, and one demonstrated low-grade areas with high-grade transformation. Four cases were oncocytic, four had clear-cell features, two had spindle cell features, and one high-grade MEC had prominent solid, cord-like, and micropapillary features. The tumours were negative for p40 (10/10), p63 (10/10), and CK5/6 (9/9). Targeted RNA sequencing demonstrated CRTC1::MAML2 in five cases, CRTC3::MAML2 in two, and a novel MAML2::CEP126 in the unusual high-grade case. In two cases with insufficient RNA, MAML2 fluorescence in situ hybridisation (FISH) showed rearrangement. Genetically-confirmed MEC may lack overt squamous differentiation by histology and immunohistochemistry. While most cases harboured canonical fusions and fit within the spectra of MEC variants with oncocytic, clear cell, and/or spindle cell features, one had a novel MAML2::CEP126 fusion and unusual morphology. In MEC without squamoid cells, the use of immunohistochemistry may hinder, rather than aid, the correct diagnosis. In such cases, MAML2 analysis is most useful. The historical definition of MEC as a carcinoma with squamoid, intermediate and mucous cells should be revisited.

The use of diagnostic patterns for interventional cytopathology during rapid on-site evaluation and final classification

Pathologist-performed fine-needle aspiration, or interventional cytopathology, is a minimally invasive, highly accurate technique for sampling and diagnosing palpable lesions. Utilizing cytomorphologic patterns during rapid onsite evaluation (ROSE) and final classification is one of many strategies that an interventional cytopathologist can employ to simplify the diagnostic approach. Herein, we provide an overview of the salient cytomorphologic patterns encountered in common specimens obtained by the interventional cytopathologist, including major salivary glands, the thyroid gland, and superficial lymph nodes. The topics covered should provide a primer for those interested in utilizing a site-specific, pattern-based approach to cytopathologic evaluation. In summary, cytomorphologic patterns can be used during ROSE to establish adequacy, build a differential diagnosis, and to appropriately triage the specimen for additional investigation, such as microbiology cultures, a liquid-based preparation, a cell block preparation, flow cytometry, chemical analysis, or molecular diagnostic tests. Finally, this approach can be applied at the time of diagnosis to suggest additional ancillary studies, such as immunohistochemistry, and to inform accurate and definitive classification.

Salivary duct carcinoma: A report of 70 FNA cases and review of the literature

BACKGROUND

Although usually recognized as malignant, fine-needle aspiration (FNA) biopsy of salivary duct carcinoma (SDC) has been confused with other primary salivary gland (SG) neoplasms. This article undertook an analysis of a large collection of SDC FNA cases to assess diagnostic accuracy, specificity, and cytopathology.

METHODS

Cytopathology files were searched for SDC with histopathologic validation. FNA biopsy smears were performed using standard techniques.

RESULTS

Seventy cases from 56 patients (M:F, 1.9:1; age range, 26-92 years; mean age, 65 years) met inclusion criteria. All had tissue confirmation of SDC. FNA sites included: parotid gland (42, 60% cases), neck (10), submandibular gland (7), pre-/post-auricular area (5), face/cheek (3), mediastinal lymph nodes (2), and clavicle (1). Aspirates were from primary (52, 74%), metastatic (12, 17%), and locally recurrent (6, 9%) neoplasms. FNA diagnoses included: SDC (19, 27%), favor/suspicious for SDC (7, 10%), high-grade carcinoma (11), adenocarcinoma (9), carcinoma (6), malignant (6), SG neoplasm (5), atypia (3), SDC versus another malignancy (2), and pleomorphic adenoma (2). Large polygonal cells in groups and single forms showed cribriforming, variable necrosis, pseudopapillae, and oncocytic change. Androgen receptor staining was positive in all cases.

CONCLUSIONS

FNA biopsy is accurate and reliable in classifying SDC as a malignant neoplasm, but much less so for identification as a specific tumor type. Using the Milan system, 86% of aspirates were classified as either malignant or suspicious for malignancy. A recurring pitfall includes sampling error in cases of SDC ex pleomorphic adenoma.

Breast Cancer Metastasis to the Parotid: A Case Report with Imaging Findings

Patient: Female, 59-year-old

Final Diagnosis: Breast cancer metastasis to the parotid

Symptoms: Growing mass in the parotid gland

Medication:—

Clinical Procedure: —

Specialty: Radiology

Practical immunohistochemistry in the classification of salivary gland neoplasms

Diagnosis of salivary gland neoplasms can be challenging for surgical pathologists due to low incidence of tumors as well as overlapping histologic features. On small biopsy, the most important information to be conveyed for clinical management is the distinction between a benign/low grade tumor and a high grade carcinoma. This review will discuss the differential diagnosis of salivary gland tumors based on four broad morphologic patterns: basaloid/tubular/cribriform, (micro)cystic/secretory/mucinous, solid-nested/clear-spindled, and oncocytic/oncocytoid. With the assistance of immunohistochemistry, demonstration of the number of cell types (mainly epithelial versus myoepithelial/basal) can further subclassify tumors within these morphologic categories. Additional tumor-specific immunomarkers are useful in some cases. Underlying tumor-specific genetic anomalies can be of value, however, immunohistochemical correlates are only available for some. When used judiciously, in the correct morphologic context, and with knowledge of their limitations, immunohistochemical stains can aid in differentiating tumors with similar morphology.

Treatment patterns and outcomes of palliative systemic therapy in patients with salivary duct carcinoma and adenocarcinoma, not otherwise specified

BACKGROUND

Salivary duct carcinoma (SDC) and adenocarcinoma, not otherwise specified (adeno-NOS), are rare salivary gland cancers. Data on the efficacy of systemic therapy for these diseases are limited.

METHODS

Data were retrospectively collected from patients seen at The University of Texas MD Anderson Cancer Center during 1990 to 2020. Objective response rate (ORR) was assessed per RECIST v1.1. Recurrence-free survival (RFS), progression-free survival (PFS), and overall survival (OS) were assessed by Kaplan-Meier method. Cox regression model was performed to identify predictors of survival.

RESULTS

The analysis included 200 patients (110 with SDC and 90 with adeno-NOS); 77% had androgen-receptor-positive tumors and 47% had HER2-positive (2+-3+) tumors. Most patients without metastasis at diagnosis underwent surgery (98%) and postoperative radiotherapy (87%). Recurrence rate was 55%, and the median RFS was 2 years. Nodal involvement and positive surgical margins were associated with recurrence (P < .005). Among patients with stage IVA-B disease, addition of systemic therapy to local therapy increased OS (P = .049). The most-used palliative-systemic-therapy regimen was platinum doublet ± trastuzumab. For first-line therapy, the ORR and median PFS were 33% and 5.76 months, respectively, and for second-line therapy the ORR and median PFS were 25% and 5.3 months, respectively. ORR and PFS were higher with HER2-targeting agents. Median OS was 5 years overall and 2 years for metastatic disease. Older age and higher stage were associated with worse OS.

CONCLUSION

Adding systemic therapy to local therapy may improve outcomes of patients with locoregionally advanced SDC or adeno-NOS. Except for HER2-targeted therapy, response to palliative systemic therapy is limited. These findings may be used as a benchmark for future drug development.

An Overview on the Histogenesis and Morphogenesis of Salivary Gland Neoplasms and Evolving Diagnostic Approaches

Simple Summary

Diagnosing salivary gland neoplasms (SGN) remain a challenge, given their underlying biological nature and overlapping features. Evolving techniques in molecular pathology have uncovered genetic mutations resulting in these tumors. This review delves into the molecular etiopatho-genesis of SGN, highlighting advanced diagnostic protocols that may facilitate the identification and therapy of a variety of SGN.

Abstract

Salivary gland neoplasms (SGN) remain a diagnostic dilemma due to their heterogenic complex behavior. Their diverse histomorphological appearance is attributed to the underlying cellular mechanisms and differentiation into various histopathological subtypes with overlapping fea-tures. Diagnostic tools such as fine needle aspiration biopsy, computerized tomography, magnetic resonance imaging, and positron emission tomography help evaluate the structure and assess the staging of SGN. Advances in molecular pathology have uncovered genetic patterns and oncogenes by immunohistochemistry, fluorescent in situ hybridization, and next–generation sequencing, that may potentially contribute to innovating diagnostic approaches in identifying various SGN. Surgical resection is the principal treatment for most SGN. Other modalities such as radiotherapy, chemotherapy, targeted therapy (agents like tyrosine kinase inhibitors, monoclonal antibodies, and proteasome inhibitors), and potential hormone therapy may be applied, depending on the clinical behaviors, histopathologic grading, tumor stage and location, and the extent of tissue invasion. This review delves into the molecular pathways of salivary gland tumorigenesis, highlighting recent diagnostic protocols that may facilitate the identification and management of SGN.

Immunocytochemistry for diagnostic cytopathology-A practical guide

Cytological specimens, which are obtained by minimally invasive methods, are an excellent source of diagnostic material. Sometimes they are the only material available for diagnosis as well as for prognostic/predictive markers. When cytomorphology is not straightforward, ancillary tests may be required for a definitive diagnosis to guide clinical management. Immunocytochemistry (ICC) is the most common and practical ancillary tool used to reach a diagnosis when cytomorphology is equivocal, to differentiate entities with overlapping morphological features, and to determine the cell lineage and the site of origin of a metastatic neoplasm. Numerous immunomarkers are available, and some are expressed in multiple neoplasms. To rule out entities within a differential diagnosis, the use of more than one marker, sometimes panels, is necessary. ICC panels for diagnostic purposes should be customised based on the clinical context and cytomorphology, and the markers should be used judiciously to preserve material for additional tests for targeted therapies in the appropriate setting. This review offers a practical guide for the use of ICC for diagnostic cytopathology, covering the most commonly encountered non-hematolymphoid diagnostic scenarios in various body sites.

Diagnostic discrepancy in second opinion reviews of primary epithelial neoplasms involving salivary gland: An 11-year experience from a tertiary referral center focusing on useful pathologic approaches and potential clinical impacts

AIMS

In the era of precision medicine, accurate pathologic diagnoses are crucial for appropriate management.

METHODS

We herein described the histologic features and clinical impacts of 66 salivary gland epithelial neoplasms in which the diagnosis was altered after expert review.

RESULTS

The most common revised diagnosis was that of salivary duct carcinoma (SDC, n = 12), adenoid cystic carcinoma (n = 12), and myoepithelial carcinoma (n = 10). The most common initial diagnosis was mucoepidermoid carcinoma (n = 19) with SDC being the most common revised diagnosis (7/19). Thirteen salivary gland carcinomas were initially diagnosed as benign entities, whereas five benign tumors were initially interpreted as carcinoma. The change in diagnosis was considered to be clinically significant in 65 (97%) cases.

CONCLUSIONS

Given their rarity, salivary gland neoplasms are prone to diagnostic inaccuracy and discrepancy. A constellation of histologic features and ancillary studies are useful in reaching the correct diagnosis, which can have significant clinical impacts.

Rare Diseases of the Salivary Glands and of Facial Nerve

Salivary gland diseases are rare. In the European Union (EU) a disease is considered to be rare if not more than 5 of 10,000 people are affected by it. According to estimates in Germany are about 4 million people with a rare disease. In the EU are about 30 million people with rare diseases [1]. In the present work most of the described diseases of salivary glands and of the facial nerve fall in this category. They form a very heterogeneous group whose treatment takes place mainly in specialized centers. Still, it is essential for the otolaryngologist to identify and to diagnose these diseases in order to initiate the right therapeutic steps. The work is a compilation of innate andacquired rare salivary gland disorders and of rare facial nerve disorders. The etiologies of inflammatory diseases, autoimmune disorders and tumors are taken into account. For the individual topics, the current literature, if available, was evaluated and turned into summarized facts. In this context the development of new processes, diagnostics, imaging and therapy are considered. Genetic backgrounds of salivary gland tumors and the trends in the treatment of tumorous lesions of the facial nerve are picked up. Furthermore, also rare diseases of the salivary glands in childhood are described. Some of them can occur in adults as well, but differ in frequency and symptoms. Due to the rarity of these diseases, it is recommended to tread these in centers with special expertise for it. Finally, the difficulties of initiation of studies and the problems of establishing disease registries concerning salivary gland disorders are discussed. This is very relevant because these pathologies are comparatively seldom.

Parotid Salivary Duct Carcinoma With a Prominent Squamous Component: Immunohistochemical Profile, Diagnostic Pitfalls, and Therapeutic Implications

Salivary duct carcinoma of the parotid gland is a highly aggressive epithelial malignancy morphologically resembling high-grade, invasive, and in situ breast carcinoma. It can occasionally present with variable morphology making it diagnostically challenging in cases with unusual morphological components. Ancillary testing, particularly androgen receptor (AR) positivity on immunohistochemistry, can be very helpful in cases that demonstrate extensive squamous morphology, since AR positivity is uncommon in both the primary salivary gland and metastatic squamous cell carcinomas to the parotid. In this report, we describe a case of salivary duct carcinoma that showed only a squamous cell carcinoma component on the initial primary tumor site biopsy, as well as in subsequent contralateral neck lymph node and skin metastases. Apart from the variable morphology, the typical salivary duct and squamous cell carcinoma tumor components also showed significant immunohistochemical differences, including differential staining of human epidermal growth factor receptor 2/neu. The associated diagnostic pitfalls, distinct immunoprofiles of the tumor components, helpful adjuncts for making the correct diagnosis, and associated therapeutic implications are discussed.

Molecular Pathology of Salivary Gland Neoplasms: Diagnostic, Prognostic, and Predictive Perspective

Salivary gland neoplasms are an uncommon and widely heterogeneous group of tumors. In recent years, there has been considerable progress in efforts to reveal the molecular landscape of these tumors, although it is still limited and appears to be only the tip of the iceberg. Genomic aberrations, especially specific chromosomal rearrangements including CRTC1-MAML2 and CRTC3-MAML2 in mucoepidermoid carcinoma, MYB-NFIB and MYBL1-NFIB fusions in adenoid cystic carcinoma, PLAG1 and HMGA2 alterations in pleomorphic adenoma and carcinoma ex pleomorphic adenoma, ETV6-NTRK3 and ETV6-RET in secretory carcinoma, EWSR1-ATF1 and EWSR1-CREM in clear cell carcinoma, provide new insights into the molecular pathogenesis of various salivary gland neoplasms and help to better classify them. These genetic aberrations primarily serve as diagnostic tools in salivary gland tumor diagnosis; however, some also have promise as prognostic or predictive biomarkers. This review summarizes the latest developments in molecular pathology of salivary gland tumors with a focus on distinctive molecular characteristics.

The tumor immune contexture of salivary duct carcinoma

BACKGROUND

Salivary duct carcinoma (SDC) is a rare and aggressive malignancy. Recently, biomarker studies found promising targetable alterations. In this study, we provide a descriptive analysis of tumor and immune biomarkers and survival associations.

METHODS

We extracted clinical data and performed immunohistochemistry for AR, AR-V7, HER-2, PD-L1, LAG-3, and tumor-infiltrating immune cells.

RESULTS

We included 17 patients. Age ranged from 42 to 85 years old; HER-2 was overexpressed or amplified in 65%. AR was positive in 88% of patients, while AR-V7 was positive in 13% by IHC. We found low scores of immune infiltration and a PD-L1 expression in 53%. We found no clinically significant association between biomarkers and survival outcomes.

CONCLUSION

In this small series of SDC, biomarkers do not seem to correlate with disease biology, although they provide additional treatment options. SDC may harbor a different immune profile compared to other subtypes, with an indication of T-cell dysfunction.

Adjuvant therapy in the management of operable salivary duct carcinoma: correlating evidence with a retrospective review

Background:

Salivary duct carcinoma (SDC) is an extremely rare and aggressive subtype of salivary gland cancer with high morbidity and mortality and poor response to treatment. The current options of treatment include radical surgery followed by radiotherapy (RT) with or without chemotherapy. The aim of this study was to analyse the patterns of recurrences, possible predictors of outcome and role of RT in a cohort of patients with non-metastatic SDC.

Methods:

A retrospective review of patients treated between 2010 and 2019 with histologically proven non-metastatic SDC was conducted.

Results:

Sixteen patients were included in the series. Median follow-up was 25 months. Progression-free survival (PFS) and overall survival (OS) at 12 months were 61% and 80%, respectively. Seven out of the 16 patients had disease progression, distant metastases being most frequent. Four patients died due to disease progression. PFS was significantly worse for patients with pathological neck node positivity (p = 0·036) and peri-parotid nodes (p = 0·007). Local control was significantly associated with RT (p = 0·011). Addition of any chemotherapy, regardless of either concurrent or adjuvant, had no impact on the PFS or OS. Pathological neck node positivity with nodal stage of N2 or higher correlated significantly with worse OS (p = 0·031).

Conclusion:

Salivary ductal carcinoma is an aggressive malignancy with high metastatic potential. Inferior prognosis was observed among patients who had metastatic deposits in either cervical nodes or peri-parotid nodes on histopathology. As systemic failures are more predominant among these patients, larger prospective trials are needed to formulate an optimum strategy for choice and sequencing of first-line systemic therapy.

Primary and Secondary/ Metastatic Salivary Duct Carcinoma Presenting within the Sinonasal Tract

Traditionally, sinonasal adenocarcinomas have been subdivided into intestinal (ITAC) and non-intestinal (non-ITAC) categories. The latter encompasses salivary-type adenocarcinomas originating from the seromucinous glands of the sinonasal mucosa and non-salivary adenocarcinomas. The non-salivary adenocarcinoma category is further subdivided into low-and high-grade variants. Among salivary-type sinonasal adenocarcinomas, tumors recapitulating salivary duct carcinoma (SDC) are exceedingly rare, but some might have been lumped into the high-grade non-ITAC category. To date, only three primary SDCs originating in the sinonasal tract have been reported. We herein describe 7 cases of SDC including one previously reported case (4 primary sinonasal, 3 metastatic/ extension from parotid gland SDC). The primary tumors affected 3 males and one female aged 60 - 75. Different sites were involved by the primary tumors while the secondary tumors affected the sphenoidal (2) and the frontal + maxillary (1) sinuses. Three primary tumors were de novo high-grade SDC and one was confined to contours of a pre-existing pleomorphic adenoma. All 3 secondary tumors were SDC ex pleomorphic adenoma of the parotid with a long history of recurrences, ultimately involving the sinonasal tract. Androgen receptor was positive in 7/7 cases. Four of 6 cases were strongly HER2/neu + (either score 3 + or with verified amplification). This small case series adds to the delineation of primary sinonasal SDC highlighting that almost half of invasive SDC presenting within sinonasal tract indeed represents extension or metastasis from a parotid gland primary. There is a tendency towards overrepresentation of HER2/neu-positive cases in both categories (primary and metastatic), but this needs clarification in larger studies.

Salivary Duct Carcinoma: An Aggressive Salivary Gland Carcinoma with Morphologic Variants, Newly Identified Molecular Characteristics, and Emerging Treatment Modalities

Salivary duct carcinoma (SDC) is a rare, aggressive salivary gland malignancy with significant mortality. Morphologically, most tumors are characterized by apocrine differentiation with a typical immunophenotype of androgen receptor positive/gross cystic disease fluid protein positive/estrogen receptor negative/progesterone receptor negative. Several morphologic variants of SDC exist, representing diagnostic pitfalls. Several differential diagnoses should be considered because prognosis, treatment, and management may be different from SDC. For SDC, current treatment strategies are aggressive and commonly include surgical excision with lymph node dissection and adjuvant radiotherapy. Continued research is examining the utility of androgen deprivation therapy and targeted molecular therapy.

Primary squamous cell carcinoma of the salivary gland: immunohistochemical analysis and comparison with metastatic squamous cell carcinoma

BACKGROUND

Primary squamous cell carcinoma (SCC) of the salivary gland is a rare disease, and distinguishing primary SCC from metastatic SCC is difficult. This study investigated the histological and immunohistochemical differences between primary and metastatic salivary gland SCC to improve the accuracy of diagnosis and to explore the pathogenesis of this disease.

METHODS

Data of 16 patients who underwent surgery for SCC of salivary glands between 2000 and 2018 at Asan Medical Center were retrieved. Eight patients had a history of SCC at other sites, and eight patients had only salivary gland SCC. Immunostaining for p16, p53, androgen receptor (AR), gross cystic disease fluid protein 15 (GCDFP-15), and c-erbB2, as well as mucicarmine staining, were compared between the two groups.

RESULTS

Most tumors were located in the center of the salivary glands with extraparenchymal extension. The histology of primary SCC of the salivary gland was consistent with moderately differentiated SCC with extensive desmoplastic reaction and peritumoral inflammation. Involvement of the salivary gland ducts and transition into the ductal epithelium were observed in two cases. Metastatic SCC resembled the primary tumor histologically and was associated with central necrosis. Both groups exhibited negative mucin staining. Two, one, and one primary SCC case exhibited AR, GCDFP-15, and c-erbB2 positivity, respectively.

CONCLUSIONS

A subset of primary SCCs originated in salivary ducts or was related to salivary duct carcinoma. Distinguishing primary from metastatic SCC of the salivary gland is difficult using histologic features and immunoprofiles. A comprehensive review of the medical history is essential.

Metastatic colon cancer of the small intestine diagnosed using genetic analysis: a case report

BACKGROUND

Intestinal-type adenocarcinoma is widely detected in the gastrointestinal tract, head and neck, lower respiratory and urinary systems. Determining the nature (monoclonal or multicentric) of the intestinal adenocarcinoma is sometimes a diagnostic challenge owing to its occurrence at various locations of the body, especially in the lower gastrointestinal tract. Herein, we successfully diagnosed metastatic colon cancer in the small intestine using tumor protein 53 gene (TP53) mutation analysis.

CASE PRESENTATION

An 83-year-old woman presented with severe abdominal pain and nausea at the emergency department of the hospital. Her history included surgery and adjuvant chemotherapy for colon and breast cancers. Abdominal computed tomography revealed small intestinal dilation, which was associated with the mural nodule detected on fluorodeoxyglucose positron emission tomography. Laparoscopy-assisted small bowel resection was performed based on the diagnosis of small bowel obstruction, probably due to recurrence of the colon or breast cancer. Macroscopically, an ulcerated tumor was present in the resected small intestine. Histologically, the cancer cells showed infiltrative growth of colonic dysplastic glands, whose non-specific finding made it difficult to determine the relationship with past colon cancers. Retrospective pathological examination confirmed that the previous breast and colon carcinomas were primary cancers. Immunohistochemical analysis revealed that the small intestinal and colon cancer cells showed diffuse positive tumor protein 53 (p53) expression. However, the breast cancer cells showed only weakly positive p53 expression. In addition, TP53 mutational analysis detected an identical missense mutation (p.T211I) between the two intestinal cancers. Moreover, further molecular genetic work-up revealed that both small intestinal and colon adenocarcinomas harbored an identical missense mutation (p.G12D) of KRAS gene. In conclusion, the small intestinal cancer in this case was identified as a metastatic adenocarcinoma arising from a past colon cancer.

CONCLUSIONS

Genetic analyses help in clarifying the identity of the cells in multiple cancer cases. In morphologically indeterminate cases, molecular analysis of common cancer-related genes can be useful for a precise and reproducible diagnosis.

Systemic therapy in the management of recurrent or metastatic salivary duct carcinoma: A systematic review

BACKGROUND

Salivary duct carcinoma (SDC) is an aggressive subtype of salivary gland cancer. Approximately half of SDC patients will develop recurrences or metastases. Therapeutic palliative therapy is therefore often needed. The majority of SDC tumors expresses the androgen receptor (AR) and one-third expresses human epidermal growth factor receptor 2 (HER2), both are potential therapeutic targets. The aim of this paper is to systematically review and summarize the evidence on systemic palliative therapy for SDC and to provide treatment recommendations.

MATERIALS AND METHODS

Electronic libraries were systematically searched with a broad search strategy to identify studies where SDC patients received systemic therapy. Due to the rarity of SDC no restrictions were placed on study designs.

RESULTS

The search resulted in 2014 articles of which 153 were full-text analyzed. Forty-five studies were included in the analysis, which included in total 256 SDC patients receiving systemic therapy. Two phase 2 trials primarily including SDC patients were identified. The majority of the studies were case series or case reports, resulting in an overall low quality of available evidence. Based on studies including ≥ 5 SDC patients, objective responses to HER2 targeting agents were observed in 60-70%, to AR pathway agents in 18-53% and to chemotherapy in 10-50%.

CONCLUSION

For AR or HER2 positive SDC, agents targeting these pathways are the cornerstone for palliative treatment. Regarding chemotherapy, the combination of carboplatin combined with a taxane is best studied. Regarding other targeted agents and immunotherapy evidence is anecdotal, limiting formulation of treatment recommendations for these antineoplastic agents.

Head and Neck Cancers, Version 2.2020, NCCN Clinical Practice Guidelines in Oncology

Treatment is complex for patients with head and neck (H&N) cancers with specific site of disease, stage, and pathologic findings guiding treatment decision-making. Treatment planning for H&N cancers involves a multidisciplinary team of experts. This article describes supportive care recommendations in the NCCN Guidelines for Head and Neck Cancers, as well as the rationale supporting a new section on imaging recommendations for patients with H&N cancers. This article also describes updates to treatment recommendations for patients with very advanced H&N cancers and salivary gland tumors, specifically systemic therapy recommendations.

A 10-year review of primary major salivary gland cancers

Primary salivary gland cancers comprise a heterogeneous group of histological entities and represent less than 5% of head and neck malignancies. Surgical resection is the main treatment, and adjuvant radiotherapy is performed in selected cases. Chemotherapy is an option in metastatic or recurrent disease, with poor evidence. We aimed to review a 10-year experience of a cancer centre on major salivary gland cancers, focusing on clinical, pathological, treatment and patients' outcomes data. A total of 93 patients were identified, median age at diagnosis was 64 years (IQR, 23), and 51.6% were male. The parotid gland was the site of origin in 76.3% of cases. The most frequent histological type was salivary duct carcinoma (21.5%). All patients were submitted to surgery and adjuvant radiotherapy was performed in 74.2%. From 26 patients diagnosed with metastatic disease, 9 were treated with systemic therapy. At 8 years, disease-free survival was 54.6% and overall survival was 48.4%. Male sex, salivary duct carcinoma, stage pT3-4, stage pN2-3, high histologic grade, lymphovascular invasion and perineural invasion were negative prognostic indicators for disease-free survival and overall survival. Extracapsular spread was a negative prognostic indicator for overall survival. In the multivariable analysis, histological type-salivary duct carcinoma-kept significant negative impact in disease-free survival and high histologic grade in overall survival. The most frequent histological type was salivary duct carcinoma, which is estimated to represent only 9% of salivary tumours. Patients with salivary duct carcinoma relapsed more than other histological types. High histologic grade was a negative prognostic indicator for overall survival.

Low-grade Apocrine Intraductal Carcinoma: Expanding the Morphologic and Molecular Spectrum of an Enigmatic Salivary Gland Tumor

Intraductal carcinoma (IDC) is the current designation for a salivary gland neoplasm previously referred to as "low-grade salivary duct carcinoma" and "low-grade cribriform cystadenocarcinoma," among others. IDC is conceptually believed to be similar to ductal carcinoma in-situ of the breast. Although IDC is one entity in the current WHO Classification of Head and Neck Tumors, recent studies have suggested that at least three subtypes exist: a low-grade, intercalated duct-like variant with frequent RET rearrangements; a high-grade apocrine variant with complex, salivary duct carcinoma-like genetics; and a mixed variant. We sought to characterize an unusual form of low-grade, purely apocrine IDC. Three cases of apocrine-type IDC with low-grade histology were retrieved from the authors' consultation files. Immunohistochemistry for androgen receptor, GCDFP-15, S100, smooth muscle actin, and p40 was performed. A custom, targeted next generation sequencing (NGS) panel including 1425 cancer-related genes was also done on all cases. All three cases developed in the parotid glands of men, aged 51, 63, and 73 years (mean, 62 years). All cases consisted of large, rounded macrocysts surrounded by smaller nests which were lined by cells with abundant granular eosinophilic cytoplasm and large round nuclei with prominent nucleoli. Pleomorphism was mild, the mitotic rate was low, and necrosis was absent. No cases had any invasive foci or areas of intercalated duct-like morphology. By immunohistochemistry, all cases were diffusely positive for androgen receptor and GCDFP-15, surrounded entirely by an intact layer of small myoepithelial cells positive for S100, smooth muscle actin, and p40. Targeted NGS results were obtained from two cases: both harbored HRAS mutations and copy number losses in TP53, while one case each harbored mutations in PIK3CA, SPEN, and ATM. Fusions were absent in both cases. All three patients were treated by surgery alone, and are currently free of disease (follow up 12-190 months). This study confirms the existence of a low-grade, purely apocrine form of IDC. In its pure form, i.e., without an intercalated duct-type component, low-grade apocrine IDC is genetically similar to high-grade salivary duct carcinoma, with frequent HRAS and PI3K pathway mutations. Despite its molecular similarities to the aggressive salivary duct carcinoma, low-grade apocrine IDC appears to behave in a very indolent manner, supporting is classification as a non-invasive neoplasm, and underscoring the need to distinguish these tumors from each other.

Intensity Modulated Radiotherapy (IMRT) With Carbon Ion Boost in the Multimodal Treatment of Salivary Duct Carcinoma

Background: To assess outcomes and treatment related toxicity following intensity-modulated radiotherapy (IMRT) and a Carbon Ion Radiotherapy (CIRT) boost for salivary duct carcinoma (SDC).

Methods: Twenty-eight consecutive patients with SDC who underwent a postoperative (82%) or definitive (18%) radiation therapy between 2010 and 2017 were assessed in this retrospective single-center analysis. CIRT boost was delivered with median 18 Gy(RBE) in 6 daily fractions, followed by an TomoTherapy^®-based IMRT (median 54 Gy in 27 daily fractions). Treatment-related acute toxicity was assessed according to CTCAE Version 4.

Results: Tumors were most commonly located in the major salivary glands (n = 25; 89%); 23 patients (82%) received previous surgery (R0: 30%; R1: 57%; R2: 4%; RX: 19%). Median follow-up was 30 months. Four patients (14%) experienced a local relapse and 3 (11%) developed locoregional recurrence. The two-year local control (LC) and locoregional control (LRC) was 96 and 93%, respectively. Median disease-free survival (DFS) was 27 months, metastasis-free survival (MFS) was 69 months, and overall survival (OS) was 93 months. Acute grade 3 toxicity occurred in 11 patients (mucositis, dermatitis, xerostomia; n = 2 each (7%) were the most common) and 2 osteonecroses of the mandibular (grade 3) occurred. No patients experienced grade ≥4 toxicities.

Conclusions: Multimodal therapy approaches with surgery followed by IMRT and CIRT boost for SDC leads to good local and locoregional disease control. However, the frequent occurrence of distant metastases limits the prognosis and requires optimization of adjuvant systemic therapies.

Salivary Duct Carcinoma of the Submandibular Gland: A Case Report and Review of the Literature

We report a patient who presented with swelling to the left submandibular region. Imaging studies revealed an expansive heterogeneous process. The patient underwent tumor resection and a biopsy confirmed the presence of a salivary duct carcinoma. Additional treatment included chemotherapy and the patient is currently receiving palliative and supportive care for advanced metastatic disease.

Prognostic markers in salivary gland cancer and their impact on survival

BACKGROUND

The role of molecular markers in salivary gland carcinoma (SGC) is not well understood. We evaluated molecular marker expression and their prognostic value.

METHODS

Immunohistochemical analysis of 124 tumor specimens was performed to determine expression of androgen (AR), estrogen (ER), and progesterone (PR) receptors and epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), programmed death ligand 1 receptor (PD-L1), and PD-L1 in tumor-infiltrating mononuclear cell (TIMC). Survival outcomes (disease-free survival [DFS] and overall survival [OS]), pT and N classification, margin status, and treatment failure were assessed.

RESULTS

Most patients (78; 62.9%) had early-stage SGC. AR positivity and EGFR positivity were detected in 21.0% and 78.6%, respectively, of tumors. AR positivity and PD-L1 negativity were associated with locally advanced disease. PD-L1-negativity was associated with higher recurrence (38.5% vs 0%; P < .001) and worse DFS. OS and DFS were worse in patients with AR+ or HER2+ disease.

CONCLUSIONS

Several molecular markers-AR and HER2 positivity and PD-L1 negativity-were associated with worse clinical outcomes. Prospective, multi-institutional trials are needed to determine the prognostic value of these markers.

The Role of Ancillary Techniques in Salivary Gland Cytopathology Specimens

Salivary gland tumor aspiration cytology is a useful preoperative test to guide the most appropriate clinical and surgical management for these patients. Although salivary gland cytology is often useful to distinguish between non-neoplastic lesions, benign neoplasms and malignant neoplasms, there remain many challenges in this area. Specifically, these tumors are uncommon and may have considerable morphologic overlap, especially in the setting of a malignant tumor. This article reviews some of the immunohistochemical and molecular characteristics of more common salivary gland neoplasms that pathologists and cytotechnologists may encounter. When used in combination with morphologic features, such ancillary testing can be useful to further refine the differential diagnosis, more strongly favor a particular entity, or in some instances confidently provide a specific diagnosis.

Acantholytic Squamous Cell Carcinoma and Salivary Duct Carcinoma Ex-pleomorphic Adenoma of the Submandibular Gland: A Report of Two Extremely Rare Cases with an Immunohistochemical Analysis

Carcinoma ex pleomorphic adenoma (CXPA) is a malignant tumor of the salivary gland that arises from pleomorphic adenoma (PA). Squamous cell carcinoma (SCC) is extremely rare in the salivary glands. We report two cases of acantholytic SCC (ASCC) ex PA. Case 1 involved a 72-year-old female, and case 2 involved a 67-year-old male. Histologically, both cases involved PA, and salivary duct carcinoma (SDC) components, which were positive for androgen receptor (AR) and gross cystic disease fluid protein (GCDFP)-15 but negative for HER2, were seen in the intracapsular regions. The invasive components consisted of ASCC, which were positive for cytokeratin 5/6 and p63 but negative for AR and GCDFP-15. The SDC and ASCC components were positive for the epidermal growth factor receptor. In both cases, the cytoplasmic localization or decreased expression of E-cadherin was observed in the ASCC. In the early phase, CXPA might emerge as SDC, and it might change into SCC as it invades beyond the capsule due to changes in microenvironment. Also, the aberrant expression of E-cadherin is related to acantholysis in SCC.

Salivary duct carcinoma

PURPOSE OF REVIEW

The review puts new information on geno- and phenotype of salivary duct carcinoma (SDC) in the perspective of the updated 2017 WHO classification.

RECENT FINDINGS

The proportion of SDC is increasing. This may be because of a true rise in incidence, but certainly to better diagnostic tests and changed WHO definitions. In this light, a substantial proportion of carcinoma expleomorphic adenoma is now attributed to the category of SDC. 'Low-grade SDC' and 'SDC in-situ' of the former WHO classification, are now named low-grade and high-grade intraductal carcinoma (IDC), respectively. Recent series quantify biologic aggressiveness: perineural growth, vascular invasion, and extracapsular extension in lymph node metastasis are each observed in two out of three patients with SDC. Most patients die within 3 years, but once 5-year disease-free survival is reached, further disease activity is exceptional. The typical molecular biological profile with high human epidermal growth factor receptor 2 and androgen receptor expression is increasingly successfully exploited in clinical trials for advanced SDC.

SUMMARY

The aggressive SDC is increasingly diagnosed. Despite intensive combined surgery and radiation therapy, many patients recur, for whom new bullets, targeting the molecular biological mechanisms, are the subject of ongoing clinical trials.

Salivary duct carcinoma: An aggressive salivary gland malignancy with opportunities for targeted therapy

Salivary duct carcinoma (SDC) is a rare, aggressive salivary malignancy that is often diagnosed at an advanced stage. Previously, little was known about outcomes of this disease due to its rarity. In the past several years, much has been learned about salivary duct carcinoma after publication of outcomes from several large single-institution series and national database searches. Recent studies of genomic alterations have helped elucidate the biology and pathogenesis of this aggressive disease. Here we review outcomes of the disease, effects of treatment, prognostic factors, and genomic alterations in SDC. Studies of targeted therapy and promising future directions are also discussed.

Mammary analogue secretory carcinoma of salivary glands: diagnostic pitfall with distinct immunohistochemical profile and molecular features

Mammary analogue secretory carcinoma (MASC) is a newly defined entity among salivary gland malignancies which has just been established in the 4^th edition of the WHO classification of head and neck tumors. MASC (synonym: secretory carcinoma) are characterized by a specific rearangement of the ETV6 gene locus. Here, we present a series of 3 MASC cases including clinical data with follow-up for up to 26 months. All tumours immunhistochemically displayed strong positivity for cytokeratin 7, and mammaglobin, focal positivity for S100, cytokeratin 5/6 and muc-4. In contrast, immunhistochemical stainings against cytokeratin 14, hormon receptors, Her2/neu, androgen receptor and prostate-specific antigen were consistently negative. FISH analysis showed translocation of the ETV6 gene locus in the majority of tumour cell nuclei. During clinical follow-up, no local relapse or metastasis was detected. As these carcinomas are clinically and radiologically indistinguishable from other salivary gland tumours and as therapeutic approaches and prognosis might differ, we need to be able to diagnose MASC correctly.

Adenocarcinoma, Not Otherwise Specified, Arising in Accessory Lacrimal Gland: A Diagnostic Challenge

Neoplasms arising in accessory lacrimal glands are rare. We describe a 33-year-old man with adenocarcinoma arising in the left lower eyelid accessory lacrimal gland. Microscopic evaluation demonstrated an infiltrative neoplasm composed of mildly to moderately pleomorphic cells with abundant eosinophilic cytoplasm and focal intracytoplasmic vacuoles, arranged predominantly in ductules. Foci of luminal and intracytoplasmic eosinophilic secretory material and occasional mucin were noted. An in situ component was identified in the gland of Wolfring. Though perineural invasion was present, high-grade nuclear features, brisk mitotic activity, and comedonecrosis were not identified. Immunohistochemical studies were notable for immunoreactivity of the tumor cells for CK7, carcinoembryonic antigen, BRST-2, androgen receptors, and HER2/neu (2+). The neoplastic cells were negative for CK20, estrogen and progesterone receptors, S-100, p63, calponin, thyroid transcription factor-1, and prostate-specific antigen. Fluorescence in situ hybridization studies for ETV6 and MAML2 rearrangements and for HER2/neu amplification were negative. Because of the absence of unifying morphologic, immunophenotypic, and molecular genetic findings, the diagnosis of adenocarcinoma, not otherwise specified, was rendered. The patient underwent comprehensive oncologic workup, which was negative for another primary tumor and metastases. He remains disease free with a follow-up of 4 years. This case illustrates the challenges encountered in applying salivary gland tumor classification to the accessory lacrimal gland neoplasm.

Biomarker immunoprofile in salivary duct carcinomas: clinicopathological and prognostic implications with evaluation of the revised classification

Salivary duct carcinoma (SDC) is an uncommon, aggressive malignant neoplasm histologically resembling high-grade mammary ductal carcinoma. SDC can arise de novo or ex pleomorphic adenoma. To clarify the correlation of biomarker immunoprofile with clinicopathological findings and clinical outcome of SDC, we conducted immunohistochemistry for EGFR, HER2, HER3, AR, CK5/6, p53, and Ki-67, along with HER2 fluorescence in situ hybridization in 151 SDCs. SDCs ex pleomorphic adenoma more commonly overexpressed EGFR, HER2, HER3, and Ki-67 than de novo SDCs (P = 0.015, < 0.001, 0.045, and 0.02, respectively). In multivariate analysis, AR− and CK5/6+ were associated with shorter progression-free survival (P = 0.027 and 0.004, respectively). Moreover, patients with p53-extreme negative/positive demonstrated poorer overall survival (P = 0.007). On assessing the revised classification by the combination of biomarker expression, the percentages of each subtype were as follows: ‘apocrine A’ (AR+/HER2−/Ki-67-low) (24%), ‘apocrine B’ (AR+/HER2−/Ki-67-high) (18%), ‘apocrine HER2’ (AR+/HER2+) (35%), ‘HER2-enriched’ (AR−/HER2+) (12%), and ‘double negative’ (AR−/HER2−) (11%). ‘Double negative’ was further subclassified into ‘basal-like’ (EGFR and/or CK5/6+) (7%) and ‘unclassified’ (3%). Consequently, patients with ‘apocrine A’ showed a better progression-free survival than those with any other subtypes. Our revised immunoprofiling classification was valuable for predicting the survival and might be useful in personalized therapy for patients with SDC.

Sensitivity of HOXB13 as a Diagnostic Immunohistochemical Marker of Prostatic Origin in Prostate Cancer Metastases: Comparison to PSA, Prostein, Androgen Receptor, ERG, NKX3.1, PSAP, and PSMA

Aims: Determining the origin of metastases is an important task of pathologists to allow for the initiation of a tumor-specific therapy. Recently, homeobox protein Hox-B13 (HOXB13) has been suggested as a new marker for the detection of prostatic origin. The aim of this study was to evaluate the diagnostic sensitivity of HOXB13 in comparison to commonly used immunohistochemical markers for prostate cancer. Materials and methods: Histologically confirmed prostate cancer lymph node metastases from 64 cases were used to test the diagnostic value of immunohistochemical markers: prostate specific antigen (PSA), Prostatic acid phosphatase (PSAP), prostate specific membrane antigen (PSMA), homeobox gene NKX3.1, prostein, androgen receptor (AR), HOXB13, and ETS-related gene (ERG). All markers were evaluated semi-quantitatively using Remmele’s immune reactive score. Results: The detection rate of prostate origin of metastasis for single markers was 100% for NKX3.1, 98.1% for AR, 84.3% for PSMA, 80.8% for PSA, 66% for PSAP, 60.4% for HOXB13, 59.6% for prostein, and 50.0% for ERG. Conclusions: Our data suggest that HOXB13 on its own lacks sensitivity for the detection of prostatic origin. Therefore, this marker should be only used in conjunction with other markers, preferably the highly specific PSA. The combination of PSA with NKX3.1 shows a higher sensitivity and thus appears preferable in this setting.