Primary Intrathoracic Ectopic Papillary Thyroid Carcinoma, Presenting With Thoracic Spine Metastasis: A Case Presentation and Literature Review.

Thyroid cancer in ectopic thyroid tissue is a very rare entity. We report a patient with papillary thyroid cancer arising from upper mediastinal ectopic thyroid tissue. The patient presented with thoracic spine metastasis with cord compression. The patient was a 67-year-old woman, who presented with upper back pain. Magnetic resonance imaging (MRI) showed suspected metastatic disease in the second and third thoracic vertebrae (T2 and T3). She underwent laminectomy and decompression surgery at the T1-T3 level. The final pathology report showed metastatic thyroid carcinoma with papillary features. She underwent external beam radiation to the affected spine. Computerized tomography (CT) scan of the chest, abdomen, and pelvis showed a 3.0 × 2.8 × 2.3 cm soft-tissue mass in the left superior mediastinum extending into the supraclavicular region. Fluorodeoxyglucose-positron emission tomography (FDG-PET) scan showed hypermetabolic foci in the upper mediastinum. Fine needle aspiration (FNA) of the upper mediastinal mass was consistent with papillary thyroid cancer. Molecular testing from the FNA sample using Thyroseq V3 showed SQSTM1NTRK3 chromosomal rearrangement. A total thyroidectomy was performed. Pathology of the resected thyroid was benign. Pathology of the mediastinal mass showed a papillary thyroid carcinoma with focal tall cell features, forming a 4 × 2.5 × 2.5 cm mass. Surgery was followed by ablation with 100 millicuries (mci) of radioactive iodine (I-131) and external beam radiation. This case highlights the presentation of primary intrathoracic papillary thyroid cancer with SQSTM1-NTRK3 chromosomal rearrangement and the challenges in the diagnosis and management of this unique case. This patient had a very aggressive disease presentation that required multimodal treatment, including thoracic spine decompression, total thyroidectomy, primary intrathoracic goiter resection, high-dose radioactive iodine treatment, and external beam radiation to the affected spine area. SQSTM1-NTRK3 chromosomal rearrangement can be targeted by medications such as larotrectinib and endtrectinib.

Paediatric and Adolescent Breast Cancer: A Narrative Review.

Breast cancer is the most prevalent form of cancer worldwide. Every year, it affects a significant number of women in the UK and is considered one of the leading causes of cancer-related deaths globally. While breast cancer is primarily linked to adult women, its occurrence in children and adolescents is exceedingly rare. This study conducted a narrative review spanning from 1999 to 2023, examining 32 case reports to investigate the characteristics of breast cancer in the paediatric age group. These reports focused on patients under 18 years old who were diagnosed with primary glandular breast cancer, excluding cases originating from other tissues like angiosarcoma, leukaemia, and metastatic cancer. The data analysis encompassed various parameters, including gender, age, histology, receptor status, lymph node involvement, treatment methods, and genetic characteristics. From the published case reports, it was concluded that the most common type of breast cancer affecting children and adolescents is secretory breast carcinoma and predominantly occurs in females. It is typically hormone receptors negative, and the preferred treatment approach involves mastectomy as breast conservation surgery to preserve the developing breast tissue is a real challenge due to limited breast tissue volume in this age group.

Case Report: A case of complete response to entrectinib in NTRK fusion gene-positive parotid gland cancer.

Introduction: Expression of the NTRK gene is rare in solid tumors but is highly prevalent in salivary gland secretory carcinomas. Here, we report a case of a complete response to entrectinib in a patient with NTRK fusion gene-positive parotid carcinoma. Case description: The patient was a 44-year-old man who underwent total left parotidectomy and left cervical lymph node dissection for a left parotid tumor at 24 years of age. The histopathological diagnosis was mammary analog secretory carcinoma. Postoperatively, the patient received only radiation therapy. Sixteen years after the surgery, the patient became aware of a mass in the left parotid region. A close examination revealed local recurrence and multiple cervical lymph node metastases. S-1 monotherapy was started as chemotherapy but was discontinued 3 years later because of disease progression. As there was no standard treatment, a comprehensive genomic profiling test using a next-generation sequencer was performed, and the ETV6-NTRK3 fusion gene was identified. Entrectinib, an NTRK inhibitor, was immediately administered at a dose of 600 mg/day. The local recurrence rapidly shrank grossly from the beginning of treatment, and a complete response was observed 6 months later. However, creatinine levels exhibited an increase at week 68 of treatment; consequently, entrectinib dosage was lowered to 400 mg/day, leading to an immediate improvement in creatinine levels. Entrectinib was associated with additional side effects, including dysgeusia, fatigue, dizziness, and weight gain, all of which were also alleviated by the reduction in entrectinib dose. Thirty months after treatment initiation, the patient maintained a complete response and continued to receive entrectinib. Conclusion: The NTRK fusion gene should always be checked in the presence of salivary gland secretory carcinoma.

Primary inflammatory myofibroblastic tumour of the liver: a clinicopathological and genetic study including a subset with ETV6::NTRK3 fusion.

AIMS: Inflammatory myofibroblastic tumour (IMT) is an intermediate neoplasm and rarely occurs in the liver. The aim of this study was to analyse the clinicopathological and genetic features of the largest primary hepatic IMT. METHODS AND RESULTS: A total of 10 cases were identified (four males and six females aged 1-48 years, median = 35 years) from 2011 to 2021, which accounted for 2.5% of IMTs occurring in all organ systems. Histological findings revealed that myofibroblastic/fibroblastic cells with inflammatory infiltration and focal hypocellularity were observed in three children. Immunostaining showed ALK-diffuse cytoplasmic positive in six cases (six of 10; 60%) and pan-TRK nuclear positive in three cases (three of 10; 30%). Hypercellular pattern was detected in ALK-positive IMTs and obvious collagenous/myxoid matrix was observed in the pan-TRK-positive subgroup. ALK rearrangement was demonstrated in three of five interpretable ALK-positive IMTs by fluorescence in-situ hybridisation (FISH), and one case failed due to poor sample quality. Next-generation sequencing indicated an IMT with TFG::ALK and FCHSD2::ALK fusion and TP53 mutation. ETV6::NTRK3 fusion was confirmed by RT-PCR, but FISH-negative results were found in two of three cases with pan-TRK-positive IMTs. No genetic alteration was detected in one tumour. One patient died 1 year after biopsy, while nine patients survived without evidence of disease in the follow-up surveillance (17-119 months). CONCLUSIONS: This article describes the first example of primary paediatric hepatic IMTs with ETV6::NTRK3 fusion. Besides the common ALK-positive subgroup, the proportion of NTRK3 fusion is high. Recognising the association between clinicopathological and molecular alterations is critical to accurate diagnosis of hepatic IMTs.

A Parotid Gland Mammary Analogue Secretory Carcinoma in a 4-Year-Old Boy: Case Report and Literature Review.

Background: Mammary analogue secretory carcinoma (MASC) is characterized by similar histologic, immunohistochemical, and molecular features with breast secretory carcinoma. MASC usually occurs in adults. Case report: A 4-year-old boy presented with a right infra-auricular mass. Features of the tumor include solid, tubular, and papillary growth patterns, with homogenous eosinophilic secretions inside microcystic structures. Immunohistochemical stains showed strong, diffuse staining for CK7, S100, pan-TRK protein. P63 was positive in a peripheral pattern. Fluorescence in situ hybridization (FISH) analysis showed the characteristic ETV6-NTRK3 gene fusion. Conclusion: Typical histological, immunohistochemical, and molecular features are present in MASC occurring early in childhood.

Case report: EML4::NTRK3 gene fusion in a patient with metastatic lung adenocarcinoma successfully treated with entrectinib.

Rearrangements involving the neurotrophin kinase (NTRK) genes NTRK1, NTRK2 and NTRK3 with different fusion partners have been observed in both adult and pediatric solid tumors. Larotrectinib and entrectinib have been the first tumor-agnostic compounds approved for the treatment of NTRK fusion-positive tumors. Here, we report the first case of a female patient with a diagnosis of stage IV lung adenocarcinoma harboring the EML4::NTRK3 gene fusion, and successfully treated with entrectinib.

Secretory carcinoma of the salivary gland: a multi-institutional clinicopathologic study of 90 cases with emphasis on grading and prognostic factors.

Secretory carcinoma (SC) is a rare form of salivary carcinoma that was first described in 2010 and is characterized by ETV6::NTRK3 fusion in most cases. In this large retrospective study, we aimed to identify adverse clinicopathologic factors and propose a prognostically relevant grading scheme for SC. METHODS: A detailed clinicopathologic review was conducted on 90 SCs from the major and minor salivary glands. RESULTS: The median age at presentation was 50 years (range: 7-93). Sixty-nine (77%) tumours originated from major salivary glands, whereas the remaining 21 involved minor salivary glands.Six cases (7%) had cervical nodal metastasis. Only lymphovascular invasion (LVI) was associated with a risk of nodal metastasis (P < 0.05). The 5-year disease-specific survival and disease-free survival (DFS) were 98% and 87%, respectively. On univariate survival analysis, adverse prognostic factors associated with decreased DFS included minor salivary gland origin, atypical mitosis, high mitotic index, high-grade transformation (HGT), necrosis, nuclear pleomorphism, infiltrative tumour border, fibrosis at the invasive front, LVI, positive margin, and advanced pT stage (P < 0.05). When adjusted for pT stage and margin status, mitotic index, LVI, nuclear pleomorphism, and HGT remained as independent prognostic factors. CONCLUSION: We therefore propose a two-tiered grading system for SC. The low-grade SC is defined as those with <5 mitoses /10 high-power fields and no tumour necrosis, and high-grade SC as those with ≥5 mitoses /10 high-power fields and/or necrosis. This proposed grading system can be useful to risk stratify patients with SC for appropriate clinical management.

The genomic profile of double primary secretory breast carcinoma in one patient provides evidence for the treatment of such carcinoma: A case report.

Secretory breast carcinoma (SBC) is one of the rarest breast carcinomas and currently lacks a standard treatment regimen. To date, few reports on double primary SBCs have been published, especially regarding the tumors' genomic features. A 51-year-old woman with early SBC who developed a secondary SBC in the contralateral mammary tissue 140 months later was evaluated. Here, we describe for the first time the sequencing results of a Chinese patient with nonsimultaneous double-primary SBC. In addition to the ETV6-NTRK3 fusion, variants in polymorphisms of enzymes related to drug metabolism variant genes, including BCL2L11, CYP2B6, CYP2C19, ERCC1, GSTM1, GSTP1, MTHFR, NQO1, TYMS, and XRCC, were present according to 425-gene DNA sequencing. The ETV6-NTRK3 fusion site was different between the tumors; furthermore, whole-gene exon sequencing revealed that genetic variation spectrum of the two tumors was different. A POLDIP2 mutation was found in the first tumor, and HDLBP, MMP2, PLEKHA6 and ZNF285 variants were detected in the second tumor. Our findings further our understanding of the molecular pathogenesis of SBCs, especially regarding tumors occurring at different times in one patient. Further molecular analyses of such cases are warranted to improve targeted therapies for SBC.

A unique case of inflammatory myofibroblastic tumor of the liver manifesting with biloma: A case report.

Anaplastic lymphoma kinase (ALK)-negative hepatic inflammatory myofibroblastic tumors (IMTs) harboring the ETS variant transcription factor 6-neurotrophic receptor tyrosine kinase 3 (ETV6-NTRK3) fusion gene and manifesting with biloma are extremely rare, and their biological behavior is unclear. The present study reports the case of a 45-year-old female with ALK-negative IMT of the liver harboring the ETV6-NTRK3 fusion gene and manifesting with biloma. Computed tomography of the abdomen confirmed the lesions to be a low-density mass, measuring 11.2×8.5×10.5 cm, located in the left lobe of the liver, and a lower-density mass, measuring 8.5×6.1×5.9 cm, located in the interior of the tumor. As the suspicion of a malignancy remained high, surgical resection of the left hepatic lobe, including the tumor, was undertaken. Intraoperatively, a tumor (12×10×9 cm), with an unclear boundary, incomplete capsule and fish-like texture, was found in the left lateral lobe of the liver, and a biloma, measuring 8×6 cm, was identified inside the tumor. Pathological examination revealed spindle cell proliferation with infiltration of chronic inflammatory cells and mucinous degeneration. Immunohistochemical studies showed negativity for ALK, CD117, CD34, discovered on GIST-1, desmin, smooth muscle actin, S-100, CD21, pan-cytokeratin, epithelial membrane antigen, CD23 and CD35, but positivity for vimentin staining, and 5% Ki-67-positive cells. Fluorescence in situ hybridization studies assessing characteristic genetic rearrangements using ALK, RET, ROS1, MDM2, MGEA5 and ETV6 break-apart assays, revealed the presence of the ETV6-NTRK3 fusion oncogene and negativity for ALK, RET, ROS1, MDM2 and MGEA5. The patient was discharged 7 days post-operatively, without any adjuvant treatment. No recurrence of symptoms was noted at the 3-year follow-up. To the best of our knowledge, this is the first report of biloma in an ALK-negative IMT of the liver, which may increase our understanding of hepatic IMT.

Low-grade tracheal adenocarcinoma with ETV6::NTRK3 fusion: unique morphology akin to subsets of sinonasal low-grade non-intestinal-type adenocarcinoma.

The prevalence of NTRK fusions in non-small cell carcinoma (NSCLC) is only approximately 0.2%, most of which harbor NTRK1 fusions. NSCLCs with NTRK3 fusions are extremely rare. Herein, we report a case of low-grade tracheal adenocarcinoma in a 64-year-old woman. Histologically, areas of complicated tubule-papillary or cribriform patterns constituted a major component of the tumor and comprised cuboidal to columnar epithelial tumor cells with pale eosinophilic cytoplasm and cytoplasmic mucin, similar to subsets of sinonasal low-grade non-intestinal-type adenocarcinomas. Immunohistochemically, the tumor was positive for MUC5AC and MUC4 and showed nuclear expression of the pan-Trk antibody. ETV6::NTRK3 was identified by reverse transcription-polymerase chain reaction using formalin-fixed paraffin-embedded tissues. To the best of our knowledge, this is the first case of low-grade tracheal adenocarcinoma with ETV6::NTRK3 fusion. Our case illustrates that low-grade adenocarcinomas with ETV6::NTRK3 fusion may exist throughout the respiratory tract.

Cytopathological Findings of Secretory Carcinoma of the Salivary Gland and the Diagnostic Utility of Giemsa Staining.

Secretory carcinoma is a salivary gland neoplasm first described as a mammary analogue secretory carcinoma by Skalova and redesignated as a secretory carcinoma in the 2017 World Health Organization Classification of Head and Neck Tumors. Secretory carcinoma diagnosis is reliant on specific cytological and histological findings and the detection of an ETV6-NTRK3 fusion gene. Here, we examined the clinical and cytopathological features of four cases of secretory carcinoma occurring in three males and a female, aged between 39 and 74 years. All four tumors involved the parotid gland, and were found to have the ETV6-NTRK3 fusion gene. Fine-needle aspiration-based cytology smears of all tumors displayed papillary and/or dendritic pattern clusters, some of which were associated with blood vessels. The neoplastic cells displayed enlarged nuclei with fine chromatin and small, distinct, single nucleoli. Furthermore, several neoplastic cells with a characteristic vacuolated cytoplasm were identified in each specimen. Giemsa staining revealed cytoplasmic vacuolation, intracytoplasmic metachromatic secretions and/or various sized metachromatic granules, and a background of metachromatic mucin in all four specimens. Given this, we conclude that these cytological findings, especially those of the Giemsa staining, might be helpful in the diagnosis of secretory carcinoma.

Characterization of an ETV6-NTRK3 rearrangement with unusual, but highly significant FISH signal pattern in a secretory carcinoma of the salivary gland: a case report.

BACKGROUND: Fusions of neurotrophic tropomyosin receptor kinase genes NTRK1, NTRK2 and NTRK3 with various partner genes occur in both common and rare tumours and are of paramount predictive value due to the availability of very effective pan-Trk inhibitors like Larotrectinib and Entrectinib. Detection of NTRK fusions is mainly performed by fluorescence in situ hybridization (FISH) and next generation sequencing (NGS). The case described here showed a very unusual, but highly significant FISH signal pattern with an NTRK3 break apart probe, indicative of a functional NTRK3 rearrangement. CASE PRESENTATION: We describe here the case of a male patient who was originally diagnosed with an adenocarcinoma of the parotid gland without evidence of metastases. After the development of multiple lung metastases, an extensive immunohistochemical and molecular examination of archived tumour tissue including analysis of NTRK was performed. NTRK expression was detected by immunohistochemistry (IHC) and then comprehensively analysed further by FISH, quantitative reverse transcription PCR (RT-qPCR), and NGS. NTRK3 break apart FISH showed multiple and very faint single 3' signals in addition to fusion signals. Quantitative reverse transcription PCR and NGS confirmed an ETV6:exon5-NTRK3:exon15 fusion. Diagnosis was therefore revised to metastatic secretory carcinoma of the salivary gland, and the patient subsequently treated with Larotrectinib, resulting in persisting partial remission. CONCLUSIONS: Our findings underline the importance to be aware of non-canonical signal patterns during FISH analysis for detection of NTRK rearrangements. Very faint single 3' signals can indicate a functional NTRK rearrangement and therefore be of high predictive value.

KANK1-NTRK3 fusions define a subset of BRAF mutation negative renal metanephric adenomas.

BACKGROUND: Metanephric adenoma (MA) is a rare benign renal neoplasm. On occasion, MA can be difficult to differentiate from renal malignancies such as papillary renal cell carcinoma in adults and Wilms̕ tumor in children. Despite recent advancements in tumor genomics, there is limited data available regarding the genetic alterations characteristic of MA. The purpose of this study is to determine the frequency of metanephric adenoma cases exhibiting cytogenetic aberration t (9;15)(p24;q24), and to investigate the association between t (9,15) and BRAF mutation in metanephric adenoma. METHODS: This study was conducted on 28 archival formalin fixed paraffin-embedded (FFPE) specimens from patients with pathologically confirmed MA. Tissue blocks were selected for BRAF sequencing and fluorescent in situ hybridization (FISH) analysis for chromosomal rearrangement between KANK1 on chromosome 9 (9p24.3) and NTRK3 on chromosome 15 (15q25.3), which was previously characterized and described in two MA cases. RESULTS: BRAFV600E mutation was identified in 62% of our cases, 9 (38%) cases were BRAFWT, and 4 cases were uninformative. Of the 20 tumors with FISH results, two (10%) were positive for KANK1-NTRK3 fusion. Both cases were BRAFWT suggesting mutual exclusivity of BRAFV600E and KANK1-NTRK3 fusion, the first such observation in the literature. CONCLUSIONS: Our data shows that BRAF mutation in MA may not be as frequent as suggested in the literature and KANK-NTRK3 fusions may account for a subset of BRAFWT cases in younger patients. FISH analysis for KANK1-NTRK3 fusion or conventional cytogenetic analysis may be warranted to establish the diagnosis of MA in morphologically and immunohistochemically ambiguous MA cases lacking BRAF mutations.

Pan-Trk immunohistochemistry is a sensitive and specific ancillary tool for diagnosing secretory carcinoma of the salivary gland and detecting ETV6-NTRK3 fusion.

AIMS: Secretory carcinoma (SC) of the salivary gland typically harbours ETV6-NTRK3 fusion, which can be utilised clinically to assist with diagnosis. Pan-Trk inhibitor therapy has demonstrated drastic responses in patients with NTRK-translocated tumours, including SC. Pan-Trk immunohistochemistry (IHC) is emerging as a sensitive and specific tool for detecting NTRK1, NTRK2 and NTRK3 fusions in various cancers. We aimed to establish the specificity and sensitivity of pan-Trk IHC in diagnosing SC and detecting ETV6-NTRK3 fusion. A literature review on the utility of pan-Trk IHC was conducted. METHODS AND RESULTS: Pan-Trk IHC was performed on 83 salivary gland neoplasms (29 SCs and 54 non-SCs). ETV6-NTRK3 fusion status was established in 25 cases. With any staining (nuclear or cytoplasmic) as a positive threshold, the sensitivity and specificity of pan-Trk IHC were 90% and 70% in diagnosing SC, and 100% and 0% in detecting NTRK3 fusion. When only pan-Trk nuclear staining was considered as positive, the sensitivity and specificity were 69% and 100% in diagnosing SC, and 92% and 100% in detecting NTRK3 fusion. CONCLUSIONS: Nuclear pan-Trk IHC is highly specific for SC diagnosis, with a specificity approaching 100%, making it a useful and precise diagnostic tool for differentiating SC from its histological mimics. On the other hand, any pan-Trk staining (nuclear or cytoplasmic) is highly sensitive for SC, and can serve as an attractive, cheap, fast and accessible screening tool for selecting patients to undergo confirmative molecular testing for clinical trials using TRK inhibitors.

(Mammary Analogue) Secretory Carcinoma of the Nasal Cavity: Report of a Rare Case with p63 and DOG1 Expression and Uncommon Exon 4-Exon 14 ETV6-NTRK3 Fusion Diagnosed with Next Generation Sequencing.

We present a 72 years old male with a left nasal cavity (mammary analogue) secretory carcinoma (SC) which exhibited classical morphological features on light microscopical examination, diffuse strong S100 and mammoglobin positivity on immunohistochemistry, and ETV6-NTRK3 gene fusion on next generation sequencing (NGS) analysis. Unusual features of this tumor are expression of p63 and DOG1 on immunohistochemistry and the atypical junction between Exon 4 of the ETV6 gene and Exon 14 of the NTRK3 gene.

A pediatric case of pigmented epithelioid melanocytoma with chromosomal copy number alterations in 15q and 17q and a novel NTRK3-SCAPER gene fusion.

Pigmented epithelioid melanocytoma (PEM) represents a group of rare, heavily pigmented melanocytic tumors encompassing lesions previously designated as "animal-type melanomas" and "epithelioid blue nevi." Despite the association of multiple such tumors in the setting of Carney complex, most cases of PEM occur spontaneously as solitary neoplasms in otherwise healthy patients. PEM may arise in both children and adults, and has a known propensity to spread to the regional lymph nodes. Despite this latter finding, recurrence at the biopsy site or spread beyond the lymph node basin is exceptionally uncommon. Although the molecular basis for PEM continues to be characterized, findings to date suggest that this category of melanocytic neoplasia has genetic alterations distinct from those seen in common nevi, dysplastic nevi, Spitz nevi, and melanoma. Herein, we present an in-depth clinical, histopathologic, and molecular analysis of a case of PEM occurring on the scalp of a young African American girl found to have a novel NTRK3-SCAPER gene fusion.

Locally advanced mammary analogue secretory carcinoma of the parotid gland.

Mammary analogue secretory carcinoma (MASC) has recently been recognized as a salivary gland tumour that is characterized by the ETV6-NTRK3 fusion gene. A case of locally advanced MASC of the parotid gland in a 67-year-old man is presented here. The patient visited the hospital due to a large right infra-auricular mass, which had been enlarging gradually over a period of 2years. Contrast-enhanced computed tomography (CT) demonstrated a multilocular mass, 75×63mm in size, containing a fluid component with non-uniform contrast effects in the interior portion. The mass had invaded the orbit, skull base, and parapharyngeal space. The patient had neither lymph node nor distant metastasis. The tumour showed tubular and ductal proliferation lined by a single layer of neoplastic cuboidal cells with clear foamy cytoplasm. Characteristic hobnail cells were observed. Expression of ETV6-NTRK3 fusion transcript in the tumour tissues was confirmed by RT-PCR. The final diagnosis was MASC (T4bN0M0, stage IVB). The patient received cetuximab together with radiotherapy at a total dose of 66Gy. After treatment, CT showed a slightly reduced tumour volume, indicating stable disease. More than 56 months after treatment, the patient remains alive with no remarkable change in the tumour.

Anaplastic lymphoma kinase-negative uterine inflammatory myofibroblastic tumor containing the ETV6-NTRK3 fusion gene: a case report.

Inflammatory myofibroblastic tumors (IMTs) are neoplasms with low malignant potential, and the most common tumor in the lung and orbit. Their occurrence in the uterus is rare. Approximately 50% of IMT patients have anaplastic lymphoma kinase gene ( ALK) rearrangements. Recent studies described novel fusions involving ROS1, platelet-derived growth factor receptor beta ( PDGFR-ß), and ETS translocation variant ( ETV6) genes in a subset of ALK-negative patients. We report a 44-year-old woman with anemia and uterine IMT. Ultrasonography and magnetic resonance imaging revealed a myxoid degenerative myoma-like mass, 7.4 cm in maximum diameter, on the left uterine side wall. Hysterectomy was performed as a definitive treatment. Microscopic examination revealed spindle cell proliferation with numerous lymphocytes and plasma cells. Immunohistochemically, the spindle cells were negative for ALK-1, desmin, and smooth muscle actin. The pathological diagnosis was IMT arising from the uterus. Fluorescence in situ hybridization demonstrated an ETV6-neurotrophic tyrosine kinase, receptor, type 3 gene ( NTRK3) translocation but no ALK, ROS1, or PDGFR-ß translocations. Lung and abdomen computed tomography at 31 months postoperatively revealed no disease recurrence. This association of an ETV6-NTRK3 fusion oncogene with an ALK-negative uterine IMT increases our understanding of this neoplasm, which may help the development of specific therapies.

Male secretory breast cancer: case in a 6-year-old boy with a peculiar gene duplication and review of the literature.

PURPOSE: Secretory breast cancer (SBC) is one of the rarest breast cancer (BC), representing the majority of BC in childhood. Nevertheless, it elicits a lot of interest both for the peculiar morphology and the characteristic genetic features. Currently, there is no consensus on optimal treatment strategy. Therefore, it is useful to report every case in order to establish treatment algorithms. METHODS: We describe the case of a 6-year-old boy diagnosed with a SBC, with peculiar genomic and immunohistochemical features. Moreover, we carried out a review of the literature in order to analyze the present state of knowledge about this rare entity. RESULTS: To the best of our knowledge, there are only 120 cases published in literature, only 32 in males and only 2 younger than 6 years. Furthermore, this one had peculiar genomic and immunohistochemical features. Indeed, even if SBC expresses basal-cell markers, our patient had a triple-negative tumor expressing both basal and luminal cell markers. Furthermore, the boy's genomic profile revealed not only positivity for the typical SBC's translocation t(12;15), but also for a 3q28 duplication, found in his father (healthy) and paternal grandfather (with a previous BC). None were positive for BRCA mutation. This locus includes only one gene encoding for a growth factor recently linked to Early Infantile Epileptic Encephalopathy-47 and Idiopathic ventricular tachycardia. Even if the literature does not provide evidence of a pathogenic role it is not possible to exclude a cancer-predisposing activity. CONCLUSIONS: SBC is a rare type of BC, characterized by triple-negative features with an unexpectedly good prognosis. More data are needed to fully understand the behavior of this cancer and genomic profiling could be helpful in improving its diagnosis and management.

Sinonasal Secretory Carcinoma of Salivary Gland with High Grade Transformation: A Case Report of this Under-Recognized Diagnostic Entity with Prognostic and Therapeutic Implications.

Secretory carcinoma (SC) is a recently described salivary gland carcinoma with characteristic ETV6-NTRK3 fusion. In this case report, we described a SC of the maxillary sinus that underwent high grade transformation in a 61-year-old patient. The diagnosis was confirmed by the presence of ETV6 translocation. Within the sinonasal tract, SC is an important differential diagnosis especially of sinonasal adenocarcinoma, non-intestinal type (non-ITAC), as these two entities bears histologic and immunophenotypic similarity. Distinction between these two tumors can be challenging based on the morphology alone and may require additional immunohistochemical and molecular studies. It is important to recognize that SC can occur in the sinonasal tract as correctly diagnosing SC may be prognostic relevant and may provide new targeted therapeutic avenues for these patients.