Primary salivary gland-type polymorphous adenocarcinoma in the lung: A case report and literature review.

RATIONALE: Polymorphous low-grade adenocarcinoma is a low-risk infiltrative malignant tumor of the salivary glands. However, some of these tumors are more malignant than the low-grade tumors and therefore, according to the most recent recommendation of the World Health Organization, they are renamed as polymorphous adenocarcinomas (PACs). Primary polymorphous low-grade adenocarcinomas/PACs of the lungs are rare. Herein, we report a case of primary PAC of the lung with bronchial cartilage and perineural invasion, and lymph node metastasis. PATIENT CONCERNS: A 58-year-old man had developed fever half a month prior, without chills or other accompanying symptoms, and the underlying reasons were unknown. His self-measured temperature was up to 39°C, accompanied by cough and expectoration, yellow and thin sputum, and shortness of breath. The patient's general state was normal, and respiratory sounds originating from the right lung were weak. Enhancement computed tomography revealed that the bronchial lumen of the basal segment of the lower lobe of the right lung was narrow; soft tissue density nodules were seen, with a range of approximately 2.4 cm × 1.3 cm. DIAGNOSIS: Based on clinical information, morphological features, and immunohistochemistry results, the pathological diagnosis was primary PAC of the lungs. INTERVENTION: Thoracoscopic resection of the middle and lower lobes of the right lung was performed, further extended dissection of the mediastinal lymph nodes was performed. OUTCOMES: The postoperative course was uneventful. LESSONS: Primary PAC of the lung is rare and may cause misdiagnosis. When encountering a lung tumor with diverse tissue structures, uniform cell type and nerve invasion, we should consider the possibility of PAC. Morphological and immunohistochemical features can be useful for diagnosing primary PAC of the lungs.

Case Report: SMARCB1 (INI-1)-Deficient Carcinoma of the Nasal Cavity with Pure Yolk Sac Tumor Differentiation and Elevated Serum AFP Levels.

In adults, yolk sac tumors (YSTs) in the nasal cavity and paranasal sinuses are very rare. To date, only six cases have been reported in the English literature. YSTs in adults are often accompanied by cancer, teratocarcinosarcoma, and other malignant components. Here, we have reported a case of nasal tumor in a 55-year-old man with nasal obstruction and epistaxis. Morphologically, the tumor showed histological characteristics of pure YST. Immunohistochemical staining showed diffuse expression of SALL4, CDX2, and GPC-3 accompanied by sporadic expression of alpha-fetoprotein (AFP) and CD117. After 20 and 40 days of operation, the serum AFP level was 220.30 and 43.60 ng/mL (normal, <7 ng/mL), respectively, which supported the pathological diagnosis of YST. However, we further performed immunohistochemical staining and fluorescence in situ hybridization using an INI-1 probe to detect the status of INI-1 in tumor cells. The results revealed that INI-1 was absent in tumor cells. Hence, we corrected the diagnosis to SMARCB1 (INI-1)-deficient carcinoma of the nasal cavity with YST differentiation. The patient underwent surgery and adjuvant radiotherapy in our hospital without evidence of recurrence or metastasis at the 6-month follow-up. The serum AFP level had also normalized. In conclusion, our case demonstrates that INI-1-deficient carcinoma may exhibit, a pure YST differentiation and immunophenotype, and elevated serum AFP levels. In adults, YST in the nasal cavity may represent INI-1-deficient carcinoma, which may be a potential diagnostic pitfall.

Thymic adenocarcinoma accompanied by type A thymoma and pulmonary minimally invasive adenocarcinoma and harboring distinct gene alterations: A case report.

RATIONALE: Thymic adenocarcinoma is an extremely rare thymic carcinoma. The exact genetic alteration associated with thymic adenocarcinoma is unclear. Here, we report a case of thymic adenocarcinoma accompanied by type A thymoma and pulmonary minimally invasive adenocarcinoma (MIA). PATIENT CONCERNS: A 53-year-old woman presented with multiple nodules in the mediastinum and lung. Thoracic computed tomography revealed nodules in the anterior superior mediastinum and anterior mediastinum near the right pericardium and ground-glass opacity (GGO) in the right superior lobe of the lung. DIAGNOSIS: The tumor in the anterior superior mediastinum was diagnosed as primary thymic papillary adenocarcinoma. The tumor in the anterior mediastinum near the right pericardium was diagnosed as type A thymoma. The GGO of the right superior lobe of the lung was diagnosed as a MIA. INTERVENTION: The patient underwent thoracoscopic mediastinal tumor resection and partial lobectomy in our hospital. OUTCOMES: The postoperative course was uneventful. The patient is alive and free of the disease for 22 months after diagnosis. LESSONS: Thyroid transcription factor 1 (TTF-1) was positive in this case of thymic adenocarcinoma, which indicated that a thymic adenocarcinoma with TTF-1-positive may not necessarily be a metastasis of lung or thyroid adenocarcinoma. The positive staining of CD5 and CD117 can help us to confirm the thymic origin. Molecular genetic analysis indicated that these tumors harbored different mutations. The thymic adenocarcinoma and type A thymoma both had the mutation of KMT2A, but the mutation sites were different. KMT2A mutation may be a common genetic change in thymic tumorigenesis. The genetic alterations disclosed in this study will help expand the understanding of thymic tumors.

Corrigendum: Gastric Cancer Cell-Derived Exosomal MicroRNA-23a Promotes Angiogenesis by Targeting PTEN.

[This corrects the article DOI: 10.3389/fonc.2020.00326.].

Appearance and morphologic features of laryngeal tuberculosis using laryngoscopy: A retrospective cross-sectional study.

ABSTRACT: Laryngeal tuberculosis (LTB) is highly contagious and can cause permanent laryngeal damage. Therefore, correctly identifying laryngoscopic LTB lesion locations, sizes, and morphologic features are essential for LTB diagnoses. This study aimed to explore the appearance and morphologic features of LTB and correlated these features with clinical symptoms.We retrospectively analysed 39 LTB patients in our hospital between January 2013 and December 2019. Medical records, including clinical presentation, lesion appearance (locations, sizes, and morphology), complementary examination results, and histopathologic features were summarized and analysed.In this patient cohort, dysphonia and sore throat were the two most common clinical symptoms. In LTB patients with extensive lesions, ulcerative lesions were most common, and the proportion of cases with concurrent pulmonary tuberculosis (86.4%, P = .033) infection was higher, as were the positive rates of sputum smears (72.7%, P = .011) and cultures (86.4%, P = .002) than patients without concurrent pulmonary TB and with more localized and exophytic lesions. The histopathologic features of LTB-related ulcerative lesions included fewer granulomas and more areas with caseous necrosis. These lesions were more likely to have acid-fast bacilli detected with a Ziehl-Neelsen stain than exophytic lesions that rarely showed detectable bacilli.A complete knowledge regarding the visual and morphologic features of LTB on laryngoscopy is needed for the early detection and diagnosis of LTB. Our study revealed the lesion sites, sizes, and morphologic features of LTB. These parameters were also correlated with patient clinical symptoms. Future studies are needed to support and expand the results of this retrospective study.

Immune reconstitution inflammatory syndrome associated with Pneumocystis pneumonia in a patient with AIDS.

Immune reconstitution inflammatory syndrome (IRIS) after starting antiretroviral treatment for human immunodeficiency virus (HIV) infection has a wide variety of causes. Delayed diagnosis and treatment of IRIS is fatal. We report a case of a 21-year-old man with HIV infection and Pneumocystis jirovecii pneumonia. The patient presented with fever and dyspnea with deterioration of pulmonary infiltrations 5 days after starting antiretroviral treatment. We reached the diagnosis of IRIS based on radial endobronchial ultrasound (EBUS)-guided lung biopsy. In conclusion, radial EBUS-guided lung biopsy via bronchoscopy is a valuable and minimally invasive technique for the rapid diagnosis of IRIS-associated Pneumocystis jirovecii pneumonia.

LINC00858 knockdown inhibits gastric cancer cell growth and induces apoptosis through reducing WNK2 promoter methylation.

BACKGROUND: Emerging evidence indicates a regulatory role of long non-coding RNAs (lncRNAs) in the development of gastric cancer (GC), but the mechanisms underlying their function have remained largely unknown. Recent microarray-based expression profiling has led to the identification of a novel differentially expressed lncRNA, LINC00858, in GC. Subsequently, LINC00858 was found to be highly expressed in GC tissues and cells. This study was designed to clarify the functional role of LINC00858 in GC, including its effect on methylation of the WNK2 gene promoter and its downstream MAPK signaling pathway. METHODS: After exogenous over-expression and knockdown of LINC00858 and the addition of a MAPK pathway inhibitor in GC cells, we explored the effects of LINC00858 and the MAPK signaling pathway on GC cell behavior using various in vitro and in vivo assays. RESULTS: LINC00858 was found to negatively regulate WNK2 expression by enhancing its promoter methylation and to activate the MAPK signaling pathway. Moreover, we found that knockdown of LINC00858 or inhibition of the MAPK signaling pathway resulted in decreased GC cell growth, migration and invasion, as well as decreased cell cycle progression, along with increased apoptosis and decreased tumorigenicity. CONCLUSIONS: Together, these findings indicate that silencing of LINC00858 increases WNK2 expression and inhibits the MAPK signaling pathway, thereby inhibiting GC growth and development. Our data highlight LINC00858 as a potential target in GC therapy.

Gastric Cancer Cell-Derived Exosomal microRNA-23a Promotes Angiogenesis by Targeting PTEN.

Hypoxia-exposed lung cancer-released exosomal microRNA-23a (miR-23a) has been shown to enhance angiogenesis as well as vascular permeability, contributing to the close correlation between exosomal miR-23a and tumorigenesis. The current study aimed to investigate whether gastric cancer (GC) cell-derived exosomal miR-23a could induce angiogenesis and to elucidate the potential mechanisms associated with the process. Differentially expressed miRNAs in GC were initially screened from the Gene Expression Omnibus database. Target genes were selected following miRNA-mRNA prediction and subsequently verified by dual luciferase reporter assay. RT-qPCR was conducted to detect miR-23a and PTEN expression in GC tissues, cells and exosomes. Human umbilical venous endothelial cells (HUVECs) were co-cultured with GC cell-derived exosomes to assess the angiogenesis mediated by exosomes in vitro. Additionally, PTEN was overexpressed in HUVECs to analyze the mechanism by which miR-23a regulates angiogenesis. miR-23a was highly expressed in GC tissues and cells and GC cell-derived exosomes. Angiogenesis was promoted by the co-culture of HUVECs and GC cells-derived exosomes, as evidenced by the increased expression of VEGF but decreased expression of TSP-1. PTEN was targeted by miR-23a and was lowly expressed in GC tissues. In a co-culture system, miR-23a carried by GC cells-derived exosomes promoted angiogenesis via the repression of PTEN. Collectively, GC cell-derived exosomal miR-23a could promote angiogenesis and provide blood supply for growth of GC cells. This study contributes to advancement of miRNA-targeted therapeutics.

ANKHD1 promotes proliferation and invasion of non­small­cell lung cancer cells via regulating YAP oncoprotein expression and inactivating the Hippo pathway.

The ankyrin repeat and KH domain­containing 1 (ANKHD1) protein was recently reported to be a potential member of the Hippo signaling pathway. However, its role in human non­small­cell lung cancer (NSCLC) has not been extensively investigated. The aim of the present study was to examine the expression of ANKHD1 in primary human tissues and cells and determine whether it is correlated with the clinical characteristics of tumor growth. The biological functions of ANKHD1 were evaluated in vitro and in vivo. Yes­associated protein (YAP) expression and phosphorylation induced by ANKHD1 were evaluated by western blotting and immunoprecipitation. Marked upregulation of ANKHD1 protein expression was observed in NSCLC cells and tissues, which was associated with advanced pathological tumor­node­metastasis stage, lymph node metastasis and poor prognosis in patients with NSCLC. ANKHD1 overexpression also promoted the proliferation and invasion of NSCLC cells. ANKHD1 upregulation inactivated Hippo signaling via increasing YAP protein levels, as well as inhibiting YAP protein phosphorylation, whereas depletion of YAP abolished the effects of ANKHD1 on cell proliferation and invasion. Therefore, ANKHD1 may play an important role in NSCLC through regulating the YAP­dependent Hippo signaling pathway.

Endoscopic submucosal dissection of tracheal deep benign fibrous histiocytoma using hybrid knife.

Deep benign fibrous histiocytoma (FH) is an uncommon and poorly recognized tumor that arises in subcutaneous or deep soft tissue. Deep benign FH of the trachea is even more rare. Deep benign FH recurs in approximately 20% of cases, so surgical resection is the recommended treatment for FH. However, some patients are afraid of the trauma and potential complications from the resection of tracheal tumors, so they do not accept surgical resection. With the development of interventional pulmonology, bronchoscopic intervention plays a key role in the treatment of benign tracheal tumors. Novel tools have emerged in interventional pulmonology and optimized the traditional techniques. Here, we report a case of deep benign FH of the trachea with broad base relapse after electrocautery with snare, argon plasma coagulation (APC) and radiotherapy. It was treated successfully by endobronchial resection with a hybrid knife (HK) and APC. The HK is a hybrid device that combines an electrocautery knife with a water jet in one instrument. Submucosal injection and circumferential cutting and dissection of lesions as well as coagulation of bleeding can be performed only with the HK. During the 6 months follow-up, the deep benign FH of the trachea did not relapse. In the case reported herein, the HK enabled submucosal injection and circumferential cutting and dissection of lesions as well as access to submucosal lesions to gain further adequate APC treatment, thereby allowing a better clinical response than that achieved by traditional electrocautery with snare and APC. In conclusion, the HK with a water jet is a feasible and effective endoscopic method for management for benign or low-grade malignant neoplasms of the trachea, especially those with a wide base and submucosal involvement.

Deep benign fibrous histiocytoma occurring in the kidney: Case report.

RATIONALE: Deep benign fibrous histiocytoma (BFH) is relatively rare in contrast to superficial BFH involving the skin. Moreover, it was extremely rare for deep BFH occurring in the solid organ. To our knowledge, so far, only one case of deep BFH of the kidney was reported in English literature. PATIENT CONCERNS: Herein, we report another case of deep BFH located in the kidney in a 88-year-old female. She was referred to our hospital for a severe pain in the right upper abdomen. Computed tomography revealed a round low-density shadow measuring 6 cm in the kidney. DIAGNOSIS: The lesion was diagnosed as a deep BFH of the kidney, as the tumor was histologically predominately composed of bland ovoid cells arranged in a storiform pattern. INTERVENTION: The patient underwent the total resection of the right kidney with the tumor in our hospital. OUTCOMES: The postoperative course was uneventful. The patient was alive with no tumor recurrence or metastasis within 6 months of follow-up. LESSONS: We present another case of deep BFH of the kidney. Because of the rarity, the tumor may be poorly recognized. The typical storiform pattern in histology may be helpful for diagnosis. This report serves to remind that deep BFH is also a differential diagnosis for a tumor with storiform pattern in the kidney.

Pleomorphic xanthoastrocytoma inside lateral ventricle: a rare case report and literature review.

Pleomorphic xanthoastrocytoma (PXA) is a relatively rare, low grade astrocytic tumor that usually affects children as well as young adults. The reported cases were predominantly located superficially in the temporal lobe. To our knowledge, so far only two cases of PXA occurring in lateral ventricle were reported in English literature. Herein, we present the third case of PXA intra-lateral ventricle in a 28-year-old Chinese male. Histologically, the tumor was relatively well circumscribed and consisted of spindle-shaped, ovoid, and multinuclear giant cells admixed with scattered eosinophilic granular bodies, inflammatory cells, and xanthomatous cells. Immunohistochemically, the tumor cells were strongly positive for S-100, GFAP, oligo-2 and vimentin, focally positive for synaptophysin and CD34, and negative for cytokeratin, EMA, NeuN and IDH1. Ki-67 proliferation index was approximately 2%. A BRAF V600E mutation was then identified in the tumor. Based on morphologic features, the immunohistochemical staining and BRAF V600E mutation, the tumor was diagnosed as a PXA. Because of the presence of the bizarre multinuclear giant cells and xanthomatous cells and the unusual location, PXA was easily misdiagnosed as a high-grade tumor. It should be noted that PXA was also an important differential diagnosis for intraventricular tumors.

Placental transmogrification of the lung presenting as a peripheral solitary nodule in a male with the history of trauma: A case report.

RATIONALE: Placental transmogrification of the lung is a very rare lesion which was characterized by the presence of papillae resembling placental villi. Its pathogenesis still remains unclear. Some authors think that this lesion is congenital and related to hamartoma, and others advocate it is secondary change after emphysema. So far, the majority of reported cases manifested as bullous lesions, to our knowledge , only two cases presented as a solitary nodule. PATIENT CONCERNS: Herein, we report the third case presenting as a small nodule in a 49-year-old male. Chest computed tomography revealed a nodular shadow measuring 2.6 × 1.2 cm in the right lower lobe of the lung. Histologically, the tumor composed of papillary structures covered by cuboidal pneumocytes and bland clear cells and abundant capillaries in the stroma. DIAGNOSIS: The lesion was diagnosed as a placental transmogrification of the lung. INTERVENTION: The patient then underwent wedge resection in our hospital. OUTCOMES: The postoperative course was uneventful. LESSONS: The patient had a history of traffic accident half a year before the nodule was detected. This prompts placental transmogrification of the lung may at least partially represent a acquired malformation. The present case aims to raise a new suggestion for its possible nature. In our opinion, PT may simply represent a benign morphologic change rather than an independent disease. It may be encountered in both congenital and secondary lesions.

Peripheral mucous gland adenoma of the lung with parenchymal involvement and smooth muscle in the stroma: A rare case report and literature review.

RATIONALE: Mucous gland adenoma is an extremely rare benign tumor predominately presented in central bronchus. Thus far, only six cases located in the periphery have been reported in English literature. PATIENT CONCERNS: Herein, we report a case located in periphery of the lung with parenchymal involvement in a 59-year-old female. Histologically, the tumor appeared as peripheral lobulated and solid mass with the pushing border. The tumor was composed of abundant irregular glands, mucus-filled acini and tubules lined by bland cuboidal to columnar mucus-secreting epithelial cells lacking cellular atypia and mitotic activities. Moreover, the tumor contained fibromyxoid stroma with smooth muscular bundles and prominent lymph follicles, which has not been reported in previous cases. DIAGNOSIS: Based on the morphological profile and immunohistochemical staining, the tumor was diagnosed as a mucous gland adenoma. INTERVENTION: The patient then underwent wedge resection in our hospital. OUTCOMES: The patient was alive with no tumor recurrence or metastasis within 16 months of follow-up. LESSONS: We report a peculiar case of mucous gland adenoma that occurred in the periphery of the lung and involved the parenchyma. The present case reported the smooth muscular bundles presenting in the stroma, which could broaden the histologic profile of the tumor.

MST1 inhibits cell proliferation and invasion of non-small-cell lung cancer by regulating YAP phosphorylation and Hippo pathway.

Mammalian ste20-like kinase 1 (MST1) is a Ser/Thr kinase involved in cell proliferation, apoptosis, and embryonic development. MST1 is also an important member of the Hippo pathway which can regulate organ size and cell proliferation. Growing evidence indicates that MST1 influences cell proliferation through different pathways including Wnt, Akt, JNK, and Hippo pathways in different cells respectively. However, little is known about the role and mechanism of MST1 in lung cancer. In this study, we aimed to assess the biological functions of MST1 in non-small-cell lung cancer (NSCLC). We investigated expression of MST1 in lung cancer cell lines and one human bronchial epithelium cell line (HBE) by Western blot. The results confirmed that MST1 expression was higher in HBE cells, but significantly lower in NSCLC cells. Moreover, MST1 was either overexpressed or depleted in NSCLC cell lines, and the results confirmed that MST1 could markedly inhibit cell proliferation and invasion through regulating the Hippo pathway and Yes-associated protein (YAP) phosphorylation. These results indicate that MST1 may play an important role in NSCLC and may serve as a potential therapeutic target for NSCLC.

Radiological presentation of chondromyxoid fibroma in the sellar region: A CARE-compliant article and literature review.

RATIONALE: Chondromyxoid fibroma (CMF) is a rare benign bone neoplasm which often occurs in the lower extremities. Little is known about the radiological and histological presentation of CMF in the sellar region. PATIENT CONCERNS: A 16-year-old Asian male presented to the hospital 12 months ago with bilateral diplopia involving right visual fields, intermittent headaches, and dizziness. INTERVENTIONS: After the patient underwent enough examinations, the lesion was surgically removed by curettage. DIAGNOSIS: Postoperatively, the lesion was pathologically confirmed to be CMF. OUTCOMES: There was no recurrence at the 12-month follow-up. LESSONS: To the best of our knowledge, this is the second reported case of CMF in the sellar region which was clinically suspected to be a pituitary macroadenoma, craniopharyngioma, or schwannoma due to its location and radiographic features. We reviewed the morbidity, symptoms, radiographic features, pathological findings, and differential diagnosis of CMF. Because of its rarity, attention should be paid to avoid misdiagnosis of this lesion.

Inversin correlates with the malignant phenotype of non-small cell lung cancer and promotes the invasiveness of lung cancer cells.

Inversin, encoded by NPHP2, is one of the 10 NPHP proteins known to be involved in nephronophthisis (an autosomal recessive cystic kidney). Although the previous reports showed that inversin played an important role in embryonic development and renal diseases, its function in cancer was not revealed clearly so far. As measured by immunohistochemical staining, inversin was highly expressed in the cytoplasm of lung cancer samples (63.4%, 161/254) compared with adjacent normal lung tissues (22.0%, 11/50, p < 0.01). Moreover, its expression was positively correlated with differentiation ( p = 0.014), tumor node metastasis staging ( p = 0.007), and lymph node metastasis ( p = 0.020). The overall survival of non-small cell lung cancer patients with inversin positive expression (45.41 ± 1.800 months) was significantly reduced compared with those with inversin negative expression (51.046 ± 2.238 months, p = 0.042). Consistently, we found that the invasion capacity of A549 cells transfected with inversin was significantly stronger than that of control cells ( p < 0.05), while inversin siRNA-treatment significantly reduced cell invasion in H1299 cells ( p < 0.05). Additionally, we demonstrated that inversin could upregulate the expression of N-cadherin, Vimentin, matrix metalloproteinase-2, and matrix metalloproteinase-9. Collectively, these results indicated that inversin might promote the tumorigenicity of lung cancer cells and serve as a novel therapeutic target of non-small cell lung cancer.

Cerebellar hemangioblastoma with perivascular pseudorosette formation and glial differentiation: A case report.

Hemangioblastoma is a well-circumscribed, highly vascular, lipid-rich and low-grade tumor of uncertain histogenesis. Its histopathological features have been well established. Herein, we present a case of cerebellar hemangioblastoma in a 43-year-old woman. Histologically, the tumor was predominantly composed of cellular areas showing eosinophilic or vacuolated stromal cells arranged in nests and sheets. Focally, conventional reticular areas could be seen. Additionally, in some areas, the stromal cells were arranged radially around blood vessels, exhibiting perivascular pseudorosette structures, which were similar mostly to those of ependymomas. Immunohistochemically, the stromal cells markedly showed diffused staining for Vimentin, S-100, CD56, NSE, inhibin-a, podoplanin, alpha-Thalassemia/mental retardation syndrome X and carbonic anhydrase IX, and were negative for cytokeratin, epithelial membrane antigen, oligodendrocyte transcription factor 2, neuronal nuclear antigen, synaptophysin, isocitrate dehydrogenase 1 (R132H), P53 and CD34. Interestingly, the reticular and cellular areas either showed no or individual scattering of the GFAP-positive cells, respectively, while, the perivascular pseudorosette areas strongly and diffusely expressed GFAP. Nuclear mitosis and necrosis were not observed. The MIB-1 antibody labeling index was especially low (about 3%). Based on these findings, the patient was diagnosed with cerebellar hemangioblastoma. In the present case, we documented a distinctive histological appearance of perivascular pseudorosettes in hemangioblastoma and provided the evidence for stromal cells with glial differentiation.

Primary thyroid-like low-grade nasopharyngeal papillary adenocarcinoma: A case report and literature review.

RATIONALE: Primary thyroid-like low-grade nasopharyngeal papillary adenocarcinoma (TL-LGNPPA) is an extremely rare malignant nasopharyngeal tumor with features resembling papillary thyroid carcinoma including nuclear positive expression of thyroid transcription factor-1 (TTF-1). PATIENT CONCERNS: A 64-year-old male presented with nasal bleeding and a foreign body sensation of the nasopharynx. Laryngoscopy revealed a 2.0-cm broad-based mass with a smooth surface on the posterior wall of the nasopharynx. A biopsy was obtained. DIAGNOSES: Histopathologic examination demonstrated tumor cells arranged in both papillary and glandular architecture. The tumor cells express nuclear immunoreactivity for TTF-1. The diagnosis of TL-LGNPPA was made. INTERVENTIONS: After the patient was diagnosed with TL-LGNPPA, he underwent complete surgical resection. OUTCOMES: There was no recurrence or evidence of metastatic disease at the 12-month follow-up. LESSONS: TL-LGNPPA is easy to misdiagnose as metastatic papillary thyroid carcinoma or other relative primary adenocarcinomas. It is important to have a broad differential diagnosis and know the key features of each entity because the prognosis and clinical treatment of each may differ.