A Case of Nasal Glial Heterotopia That Can Be Misdiagnosed as Storiform Patterned Sclerotic Fibroma/Collagenoma.

OBJECTIVE: Nasal glioma, also known as nasal glial heterotopia, is a rare tumor-like lesion that often affects newborns or infants with no hereditary predisposition. CASE REPORT: A 4-year-old child with a growth on the nasal dorsum since birth was diagnosed with nasal glial heterotopia/nasal glioma. The lesion showed a sclerotic fibroma/collagenoma-like storiform pattern with entrapped glial tissue that was S100 and GFAP positive. CONCLUSION: When a biopsy of the nasal dorsum demonstrates sclerotic microscopic findings with a storiform pattern, nasal glioma should be considered before making a diagnosis in the collagen-rich tissue spectrum (collagenoma or Gardner's fibroma), and an immunohistochemical panel should be requested to demonstrate the presence of an unrecognized light microscopically visible glial component.

[Sarcomatoid carcinoma of the nasal cavity: a case report and review of the literature]. / Carcinoma sarcomatoide de fosa nasal: a propósito de un caso y revisión de la literatura.

Spindle cell carcinoma of the nasal cavity is a rare variant of squamous cell carcinoma. We report a case of a 50 year-old male presenting with a polypoid mass in the left nasal cavity. Histologically, the tumor was biphasic, composed of non-keratinizing squamous nests and a sarcomatoid stroma with positivity for CKAE1-AE3. Metastatic ipsilateral lymph nodes were present and the patient underwent radical neck dissection, followed by adjuvant radiotherapy and cisplatin. Two years after diagnosis the patient is free of disease.

Genetic basis of SMARCB1 protein loss in 22 sinonasal carcinomas.

SMARCB1-deficient sinonasal carcinoma (SNC) is an aggressive malignancy characterized by INI1 loss mostly owing to homozygous SMARCB1 deletion. With the exception of a few reported cases, these tumors have not been thoroughly studied by massive parallel sequencing (MPS). A retrospective cohort of 22 SMARCB1-deficient SNCs were studied by light microscopy, immunohistochemistry, fluorescence in situ hybridization (n = 9), targeted exome MPS (n = 12), and Fraction and Allele-Specific Copy Number Estimates from Tumor Sequencing (FACETS) (n = 10), a bioinformatics pipeline for copy number/zygosity assessment. SMARCB1-deficient SNC was found in 13 (59%) men and 9 (41%) women. Most common growth patterns were the basaloid pattern (59%), occurring mostly in men (77%), and plasmacytoid/eosinophilic/rhabdoid pattern (23%), arising mostly in women (80%). The former group was significantly younger (median age = 46 years, range = 24-54, vs 79 years, range = 66-95, p < 0.0001). Clear cell, pseudoglandular, glandular, spindle cell, and sarcomatoid features were variably present. SMARCB1-deficient SNC expressed cytokeratin (100%), p63 (72%), neuroendocrine markers (52%), CDX-2 (44%), S-100 (25%), CEA (4/4 cases), Hepatocyte (2/2 cases), and aberrant nuclear ß-catenin (1/1 case). SMARCB1 showed homozygous deletion (68%), hemizygous deletion (16%), or truncating mutations associated with copy neutral loss of heterozygosity (11%). Coexisting genetic alterations were 22q loss including loss of NF2 and CHEK2 (50%), chromosome 7 gain (25%), and TP53 V157F, CDKN2A W110∗, and CTNNB1 S45F mutations. At 2 years and 5 years, the disease-specific survival and disease-free survival were 70% and 35% and 13% and 0%, respectively. SMARCB1-deficient SNCs are phenotypically and genetically diverse, and these distinctions warrant further investigation for their biological and clinical significance.

Immunohistochemical and genetic analysis of respiratory epithelial adenomatoid hamartomas and seromucinous hamartomas: are they precursor lesions to sinonasal low-grade tubulopapillary adenocarcinomas?

Respiratory epithelial adenomatoid hamartoma (REAH) and seromucinous hamartoma (SH) are rare tumor-like lesions of the nasal cavity, paranasal sinuses, and nasopharynx. The pathogenesis of REAH/SH is still unclear. Neoplastic proliferation, chronic mechanical irritation, inflammation, or possible embryological tissue misplacement are speculated as possible mechanisms of their development. Low-grade tubulopapillary adenocarcinoma (LGTA) is a rare variant of nonsalivary, nonintestinal type sinonasal adenocarcinoma. The aim of this study was to evaluate the immunohistochemical and genetic profiles of 10 cases of REAH/SH, with serous, mucinous, and respiratory components evaluated separately and to compare these findings with the features of 9 cases of LGTA. All cases of REAH/SH and LGTA were analyzed immunohistochemically with a cocktail of mucin antigens (MUC1, MUC2, MUC4, MUC5AC, MUC6) and with epithelial (CK7, CK20, CDX2, SATB2) and myoepithelial markers (S100 protein, p63, SOX10). The next-generation sequencing assay was performed using FusionPlex Solid Tumor Kit (ArcherDx) in 10 cases of REAH/SH, and the EGFR-ZNF267 gene fusion was detected in 1 of them. Two female REAH/SH cases were assessed for the presence of clonality. Using the human androgen receptor assay, 1 case was proved to be clonal. The serous component of REAH/SH was positive for CK7/MUC1 and SOX10 similarly to LGTA. Although REAH/SH and LGTA are histopathologically and clinically separate entities, the overlap in their morphological and immunohistochemical profiles suggests that REAH/SH might be a precursor lesion of LGTA.

Predictive value of EGFR-PI3K-pAKT-mTOR-pS6 pathway in sinonasal squamous cell carcinomas. / Valor pronóstico de la ruta de EGFR-PI3K-pAKT-mTOR-pS6 en los carcinomas epidermoides nasosinusales.

BACKGROUND AND OBJECTIVES: We have previously indicated that EGFR has a role in carcinogenesis in a subgroup of sinonasal squamous cell carcinomas (SNSCC). In addition, EGFR activates 2 of the most important intracellular signalling pathways: PI3K/pAKT/mTOR/pS6 and MAP pathway kinases. The objective of this study was to evaluate the involvement of the EGFR/PI3K/pAKT/mTOR/pS6 pathway and its relationship with clinical-pathological parameters and follow-up of sinonasal squamous cell carcinoma. MATERIAL AND METHODS: The immunohistochemical expression of different components of the PI3K/AKT/mTOR/pS6 pathway and its relationship with various clinical-pathological parameters was studied in a series of 54 patients with SNSCC. RESULTS: Loss of PTEN expression was observed in 33/54 cases (61%) and pAKT, mTOR and pS6 pre-expression was observed in 19/54 cases (35%), 8/54 cases (15%), and 47/54 cases (87%), respectively. Loss of PTEN expression was related to intracranial invasion and development of regional metastases (p=0.005). Overexpression of pS6 was associated with a decrease in survival (p=0.008), presence of local recurrences (p=0.055), and worsening of overall prognosis (p=0.007). No significant relationships were observed between pAKT and mTOR expression and the clinicopathological parameters studied. CONCLUSIONS: Alterations in the expression of EGFR/PI3K/pAKT/mTOR/pS6 pathway components are common in a subgroup of SNSCC. This study reveals that the absence of pS6 overexpression is associated with better clinical outcomes. Therefore, pS6 expression could be considered as an unfavourable prognostic marker.

[Expression of CD117, MITF and NAT10 and their prognostic values in sinonasal mucosal melanoma].

Objective: To investigate the correlation between the expression of CD117, MITF, NAT10 and clinical parameters in sinonasal mucosal melanoma (SNMM). Methods: Formalin-fixed paraffin-embedded tumor specimens of 80 cases of SNMM at the Eye, Ear, Nose and Throat Hospital, Fudan University, from December 1999 to November 2013 were analyzed for CD117, MITF and NAT10 expression by immunohistochemistry. Results: There were 40 men and 40 women. The median age was 61 years, age 26 to 85 years. There was no correlation of the expression of CD117, MITF and NAT10 with the patients' age, gender, tumor site, stage, therapy method and brain metastases (P>0.05). The expression of MITF and NAT10 was associated with lymph node metastasis and the tumors were more likely to metastasize when MITF and NAT10 were positive. However, expression of CD117 had no correlation with lymph node metastasis. Log-rank test revealed that the expression of CD117 was correlated with both three-year and five survival rate (P=0.012, P=0.023; respectively) and patients with tumor having low expression of CD117 had the worse outcome. COX test revealed that low CD117 expression, advanced age and lymph node metastasis were independent risk factors (P<0.05). No significant association was found between the expression of CD117, MITF and NAT10 with disease free survival (P>0.05). Conclusions: Patients with SNMM expressing low level of CD117 have decreased survival rate. Tumors with high level of MITF and NAT10 expression are more likely to metastasize. The expression level of CD117 can be used as an important indicator for the patient survival, and the expression of MITF and NAT10 can be used as a predictor of tumor metastasis.

ß-catenin (CTNNB1) mutation and LEF1 expression in sinonasal glomangiopericytoma (sinonasal-type hemangiopericytoma).

Sinonasal glomangiopericytoma (SN-GPC) is an uncommon mesenchymal tumor with myoid differentiation. Recently, mutations in exon 3 of the gene coding for ß-catenin (CTNNB1) and its nuclear expression were discovered in SN-GPC. ß-catenin protein is a key regulatory molecule of the canonical Wnt signaling pathway. The expression of ß-catenin target proteins is not well characterized in SN-GPC. We examined three SN-GPCs by immunohistochemistry and CTNNB1 mutation analysis. All cases expressed nuclear ß-catenin. We identified CTNNB1 exon 3 mutations in two analyzable cases. Lymphoid enhancer-binding factor 1 (LEF1), a protein downstream from ß-catenin, was also expressed in all cases. Our results further characterized the activation of the Wnt signaling pathway caused by CTNNB1 exon 3 mutation and suggest the utility of LEF1 immunohistochemistry in the differential diagnosis of SN-GPC.

Frequent expression of somatostatin receptor 2a in olfactory neuroblastomas: a new and distinctive feature.

Olfactory neuroblastoma (ONB) is a malignant neuroendocrine neoplasm with a usually slow course, but with considerable recurrence rate. Many neuroendocrine tumors have shown good response to the treatment with somatostatin analogs and somatostatin radioreceptor therapy. In ONBs, there are scarce data on somatostatin-based treatment and the cellular expression of somatostatin receptors (SSTR), the prerequisite for binding and effect of somatostatin on normal and tumor cells. The aim of our study was to investigate the immunohistochemical expression of SSTR2A and SSTR5 in a cohort of 40 ONBs. In addition, tissue microarrays containing 40 high-grade sinonasal carcinomas as well as 6 sinonasal lymphomas, 3 rhabdomyosarcomas, and 3 Ewing sarcomas were evaluated. Volante system was applied for staining evaluation. Thirty cases (75%) were immunopositive for SSTR2A and 3 (7.5%) for SSTR5. Among the 30 SSTR2A-positive ONBs, 19 tumors (63.3%) scored 2+ and 11 (36.7%) scored 3+. All SSTR5-positive ONBs scored 2+. Neither sinonasal carcinomas nor sinonasal small round blue cell neoplasms expressed SSTR2A or SSTR5. The frequent expression of SSTR2A provides a rationale for radioreceptor diagnosis and therapy with SST analogs in ONBs. SSTR2A expression in ONBs is a helpful adjunct in the differential diagnosis of ONBs.

Mammary Analog Secretory Carcinoma of the Nasal Cavity: Characterization of 2 Cases and Their Distinction From Other Low-grade Sinonasal Adenocarcinomas.

Secretory carcinoma, originally described as mammary analog secretory carcinoma (MASC), is a low-grade salivary gland tumor characterized by a t(12;15)(p13;q25) translocation, resulting in an ETV6-NTRK3 gene fusion. Most MASCs are localized to the parotid gland and intraoral minor salivary glands. Moreover, ETV6-rearranged carcinomas with secretory features have been reported recently in the thyroid (with and without a history of radiation exposure), skin, and in very rare instances in the sinonasal tract. Here, we describe 2 cases of primary MASC in the sinonasal tract and provide a detailed clinical and histopathologic characterization of their morphology, immunohistochemical profile, and genetic background and highlight features allowing for its separation from its recently described molecular mimicker, ETV6-rearranged low-grade sinonasal adenocarcinoma.

SMARCB1 (INI-1)-deficient Sinonasal Carcinoma: A Series of 39 Cases Expanding the Morphologic and Clinicopathologic Spectrum of a Recently Described Entity.

To more fully characterize the clinical and pathologic spectrum of a recently described tumor entity of the sinonasal tract characterized by loss of nuclear expression of SMARCB1 (INI1), we analyzed 39 SMARCB1-deficient sinonasal carcinomas collected from multiple medical centers. The tumors affected 23 males and 16 females with an age range of 19 to 89 years (median, 52). All patients presented with locally advanced disease (T3, n=5; T4, n=27) involving the sinuses (mainly ethmoid) with variable involvement of the nasal cavity. Thirty patients received surgery and/or radiochemotherapy with curative intent. At last follow-up, 56% of patients died of disease 0 to 102 months after diagnosis (median, 15), 2 were alive with disease, and 1 died of an unrelated cause. Only 9 patients (30%) were alive without disease at last follow-up (range, 11 to 115 mo; median, 26). The original diagnosis of retrospectively identified cases was most often sinonasal undifferentiated carcinoma (n=14) and nonkeratinizing/basaloid squamous cell carcinoma (n=5). Histologically, most tumors displayed either a predominantly basaloid (61%) or plasmacytoid/rhabdoid morphology (36%). The plasmacytoid/rhabdoid form consisted of sheets of tumor cells with abundant, eccentrically placed eosinophilic cytoplasm, whereas similar cells were typically rare and singly distributed in the basaloid variant. Glandular differentiation was seen in a few tumors. None of the cases showed squamous differentiation or surface dysplasia. By immunohistochemistry, the tumors were positive for pancytokeratin (97%), CK5 (64%), p63 (55%), and CK7 (48%); and they were negative for NUT (0%). Epstein-Barr virus and high-risk human papillomavirus was not detected by in situ hybridization. Immunohistochemical loss of SMARCB1 (INI1) expression was confirmed for all 39 tumors. Investigation of other proteins in the SWI/SNF complex revealed co-loss of SMARCA2 in 4 cases, but none were SMARCA4 deficient or ARID1A deficient. Of 27 tumors with SMARCB1 fluorescence in situ hybridization analysis, 14 showed homozygous (biallelic) deletions and 7 showed heterozygous (monoallelic) deletions. SMARCB1-deficient sinonasal carcinoma represents an emerging poorly differentiated/undifferentiated sinonasal carcinoma that (1) cannot be better classified as another specific tumor type, (2) has consistent histopathologic findings (albeit with some variability) with varying proportions of plasmacytoid/rhabdoid cells, and (3) demonstrates an aggressive clinical course. This entity should be considered in any difficult-to-classify sinonasal carcinoma, as correct diagnosis will be mandatory for optimizing therapy and for further delineation of this likely underdiagnosed disease.

Checkpoint inhibition for advanced mucosal melanoma.

BACKGROUND: Whereas anti-PD-1 therapy has demonstrated a significant and durable response against advanced cutaneous melanoma, conventional chemotherapies have shown only minor benefit against advanced mucosal melanoma. OBJECTIVES: To investigate the efficacy of anti-PD-1 therapy in a small cohort of patients with mucosal melanoma of the head and neck. MATERIALS & METHODS: We analysed five patients with mucosal melanoma of the head and neck who received nivolumab or pembrolizumab, at an advanced stage. Expression of PD-L1 and PD-1 in all tumour samples was evaluated immunohistochemically. RESULTS: All patients received at least two cycles of nivolumab or pembrolizumab. The most severe adverse events were categorised as CTCAE (common terminology criteria for adverse events) Grade 2. All patients showed progressive disease after restaging at three and six months, and no partial or complete response was observed. Immunohistochemical staining demonstrated PD-L1 expression in less than 5% of tumour cells. CONCLUSION: Systemic therapy with either nivolumab or pembrolizumab showed no clinical response, however, tumour progression was identified in all patients using Response Evaluation Criteria In Solid Tumors (RECIST) v1.1 and immune-related response criteria (irRC) to evaluate tumour response.

Absence of chromosomal translocations and protein expression of ALK in sinonasal adenocarcinomas. / Ausencia de translocaciones cromosómicas y de expresión proteica de ALK en los adenocarcinomas nasosinusales.

INTRODUCTION: Chromosomal translocations at 2p23 cause overexpression of anaplastic lymphoma kinase (ALK), a receptor tyrosine kinase involved in signalling pathways that regulate cell proliferation. This translocation occurs in 5% of lung adenocarcinoma and has been demonstrated to be useful as a therapeutic target for crizotinib. sinonasal adenocarcinomas (SNAC) are histologically similar to lung adenocarcinomas; the aim of this study was to evaluate the presence of ALK alterations in SNAC. METHOD: Break-apart fluorescent in-situ hybridization was used to analyse the presence of ALK translocations in 96 tumour samples. In addition, ALK protein expression was studied by immunohistochemistry. RESULTS: The samples of SNAC did not show ALK translocation. Moreover, ALK protein expression was absent in all cases. CONCLUSIONS: These results suggest that ALK is not involved in SNAC.

Lentigo maligna - anatomic location as a potential risk factor for recurrences after non-surgical treatment.

BACKGROUND: A higher incidence of lentigo maligna (LM) recurrences on the nose was previously observed in our cohort after non-surgical treatment. OBJECTIVES: To determine histological parameters that might be related to the previously observed higher incidence of LM recurrences on the nose after non-surgical treatment. METHODS: We randomly selected 22 surgical specimens of LM on the nose and 22 on the cheek. Histopathological analysis was performed on haematoxylin and eosin stained and microphthalmia transcription factor immunohistochemically stained slides. The number of pilosebaceous units (PSU) per mm, maximum depth of atypical melanocytes along the skin appendages and maximum depth of the PSU itself were determined. RESULTS: The nose had a significantly higher density of PSU than the cheek. The atypical melanocytes extended deeper along the PSU on the nose with a mean (SD) depth of 1.29 mm (0.48) vs. a mean depth of 0.72 mm (0.30) on the cheek (P < 0.001). The maximum depth of the PSU on the nose was greater than on the cheek, mean (SD) depth of 2.28 mm (0.41) vs. 1.65 mm (0.82) (P = 0.003). CONCLUSIONS: The higher recurrence risk of LM on the nose after non-surgical treatment that we previously observed in our cohort is most likely based on a higher density of atypical melanocytes and also their deeper extension into the follicles. These results shed more light on our previous findings and learn that anatomical location is relevant for the risk of recurrence of LM after non-surgical treatment.

Melanotic PEComa of the Sinonasal Mucosa With NONO-TFE3 Fusion: An Elusive Mimic of Sinonasal Melanoma.

Perivascular epithelioid cell neoplasms (PEComas) are a family of mesenchymal tumors with features of both smooth muscle and melanocytic differentiation, with or without true melanin pigment. The highly variable morphology of PEComas results in a broad differential diagnosis that is also dependent on anatomic site. A subset demonstrates rearrangements involving the TFE3 (Xp11) locus, which can be used in diagnostically difficult cases. Here we describe a case of a melanotic PEComa with NONO-TFE3 fusion occurring in the sinonasal mucosa, as demonstrated by both next-generation sequencing and molecular cytogenetic studies. This case is the first of its kind in the literature and only the second documented PEComa harboring a NONO-TFE3 rearrangement. In light of unequivocal molecular ancillary studies, this case illustrates that PEComa must enter the differential for pigmented lesions of the sinonasal mucosa, where malignant melanoma would be much more likely to occur.

[Clinicopathologic features of non-keratinizing carcinoma of nasal cavity and paranasal sinus].

OBJECTIVE: To study the clinicopathologic features, immunophenotype, differential diagnosis and prognosis of non-keratinizing carcinoma of nasal cavity and paranasal sinus. METHODS: Four hundred and forty-one cases of squamous cell carcinoma of the nasal cavity and sinuses diagnosed in Beijing Tongren Hospital from January 2008 to August 2015 were included. Twenty-six cases of non-keratinizing carcinomas were selected. The histopathologic features and the clinicopathologic data of these twenty-six cases were retrospectively analyzed. Immunohistochemistry (two-step EnVision method) was done to evaluate the expression of CK, vimentin, CK5/6, CK7, CK8/18, p16, p53, Ki-67 etc. In situ hybridization was used to detect Epstein-Barr virus mRNA(EBER), and flow-through hybridization was used to evaluate the presence of human papilloma virus (HPV). One of the cases which HPV is positive was detected by HPV in situ hybridization and RNAscope technology. RESULTS: The mean age for the twenty-six patients (16 males, 10 females) was 51.2 years (range 22 to 79 years). Three patients had a history of inverted papilloma.Microscopically the tumors showed invasive papillary and inverted growth, and formed solid cell nests with different sizes. It was similar to papillary carcinoma of the urinary tract: the nuclei of the tumor were rounded and the nucleolus are clear. Three cases displayed transition between normal epithelium to neoplastic cells; in two cases (2/26), some tumor cells were spindle shaped. Twenty cases (20/20) were strongly positive for CK, p63; 17 cases (17/20) were strongly positive for CK5/6 and three cases (3/20) were focally positive. Sixteen cases were strongly positive for CK8/18 and three cases (3/20) were focally positive and one case was negative. Seven cases (7/20) were strongly positive for CK7 and 13 cases (13/20) were negative. Two cases (2/20) were focally positive for vimentin and eighteen (18/20) cases were negative. One case (1/20) was strongly positive for p16 and nineteen cases (19/20) were negative. Nineteen cases (19/20) were positive for p53 and one case (1/20) was negative. Ki-67 index was >50% in 11 cases. Twenty cases (20/20) were negative for AFP, NUT, S-100 protein, HMB45 and Melan A. One case was positive for HPV (6, 11, 16, 18), as detected by in situ hybridization. The HPV18 mRNA was detected by RNAscope technique. In situ hybridization were negative in all twenty cases. The mean follow-up time of the patients in this group was less than 5 years, and the prognosis needs further observation. CONCLUSIONS: Non-keratinizing squamous cell carcinoma is a rare neoplasm with distinct morphological characteristics. Its diagnosis is primarily based on the site of lesions and the histological features.Immunohistochemistry staining can aid the diagnosis and differential diagnoses. The tumor may originate from the epithelium of nasal cavity and sinus. This disease has no relation with HPV and EBV infection, and the treatment is primarily surgical excision combined with postoperative radiotherapy.

A case of radiation-induced mucosal melanoma in an immunohistochemically S-100-negative patient.

We report a case of radiation-induced mucosal melanoma in a 41-year-old woman with a history of childhood rhabdomyosarcoma of the nasal cavity that had been treated with radiotherapy. During the workup for the melanoma, the patient was found to be negative for S-100 protein on immunostaining. While many melanotic markers for the histologic confirmation of melanoma exist, they can be negative in some cases, such as ours. To the best of our knowledge, only 1 case of radiation-induced melanoma has been previously reported in the English-language literature, and in that case the patient was S-100-positive. Although our case is rare, it suggests another possible long-term adverse effect of radiotherapy. We also describe the morphologies and histology associated with diagnosing melanoma in an S-100-negative patient.

Recently described neoplasms of the sinonasal tract.

Surgical pathology of the sinonasal region (i.e., nasal cavity and the paranasal sinuses) is notoriously difficult, due in part to the remarkable diversity of neoplasms that may be encountered in this area. In addition, a number of neoplasms have been only recently described in the sinonasal tract, further compounding the difficulty for pathologists who are not yet familiar with them. This manuscript will review the clinicopathologic features of some of the recently described sinonasal tumor types: NUT midline carcinoma, HPV-related carcinoma with adenoid cystic-like features, SMARCB1 (INI-1) deficient sinonasal carcinoma, biphenotypic sinonasal sarcoma, and adamantinoma-like Ewing family tumor.