Thyroid-like low-grade nasopharyngeal papillary adenocarcinoma: A case report

Radiological features of thyroid-like low-grade nasopharyngeal papillary adenocarcinoma: case series and systematic review

PURPOSE

To comprehensively summarize the clinical data and CT/MRI characteristics of thyroid-like low-grade nasopharyngeal papillary adenocarcinoma (TL-LGNPPA).

METHODS

Twenty-seven lesions from 25 study articles identified through a systematic review and three lesions from our institution associated with TL-LGNPPA were evaluated.

RESULTS

The mean age of the patients at diagnosis was 35.7 years, and the male-to-female ratio was nearly half. The chief complaint was nasal obstruction, followed by epistaxis. All patients underwent excision. None of the patients had neck nodes or distant metastases. All patients survived with no locoregional/distant recurrence during 3-93 months of follow-up. All lesions were located at the posterior edge of the nasal septum, attached to the nasopharyngeal parietal wall, and showed no laterality. The mean lesion diameter was 1.7 cm. The margins of lesions were well-defined and lobulated, followed by well-defined smooth margins. None of lesions were associated with parapharyngeal space or skull base destruction. All lesions were iso- and low-density on non-contrast CT. Adjacent skull base sclerosis was detected in 63.6% of lesions. High signal intensity on T2-weighted imaging and mostly iso-signal intensity on T1-weighted imaging compared to muscle tissue. Most lesions were heterogeneous and exhibited moderate contrast enhancement. Relatively large lesions (≥1.4 cm) tended to be more lobulated than smooth margins compared to relatively small lesions (<1.4 cm) (p = 0.016).

CONCLUSION

We summarized the clinical and radiological features of TL-LGNPPA to facilitate accurate diagnosis and appropriate management.

Genetic profile identification and clinicopathologic characteristics analysis of the thyroid-like low-grade nasopharyngeal papillary adenocarcinoma

Thyroid-like low-grade nasopharyngeal papillary adenocarcinoma (TL-LGNPPA) is an extremely rare malignancy bearing histomorphological similarities to papillary thyroid carcinoma with good prognosis. It's important to distinguish TL-LGNPPA from other papillary tumors including nasopharyngeal papillary adenocarcinoma (NPPA), metastatic and ectopic papillary thyroid cancer, and metastasized adenocarcinomas, etc. To date, only 48 cases of TL-LGNPPA have been reported in the English literatures. Here, we reported the genomic characteristics of additional 4 cases and reviewed other reports to clarify the clinicopathological features of this tumor. In this study, 41 mutations were detected by whole-exome sequencing, but no typical driver mutations were found. Two sample with Copy Number Variations (CNV) were found (7 q22. 17 q12), of which the segment spanned the regions of RASA4, POLR2J2, SPDYE2, CCL3, CCL4, etc. Additionally, no MSI and HLA LOH were found. To our knowledge, we are the first to reveal the genetic underpinnings of this rare tumor. The clinicopathological features of TL-LGNPPA were characterized, shedding more light on the essential difference between TL-LGNPPA with other papillary tumors.

Clinicopathological Features of Thyroid-Like Low-Grade Nasopharyngeal Papillary Adenocarcinoma: A Case Report and Review of the Literature

Thyroid-like low-grade nasopharyngeal papillary adenocarcinoma (TL-LGNPPA) is an extremely rare neoplasm of the nasopharynx. Accordingly, its clinical and pathological characteristics are not well-known. We report a case of TL-LGNPPA and review the relevant literature on TL-LGNPPA. A 38-year-old Japanese woman presented with a history of nasal obstruction that had persisted for 1 month after symptoms of a common cold (e.g., low-grade fever, sore throat, and fatigue). A pedunculated tumor of ~20 mm in diameter was found on the posterior edge of the nasal septum. The tumor was endoscopically resected. Based on careful histopathological and immunohistochemical examinations, it was diagnosed as TL-LGNPPA. At 5 years after surgery, the patient remained disease-free. TL-LGNPPA has a very good prognosis, and complete resection with a sufficient safety margin is recommended as the first-line treatment. The morphological characteristics and immunohistochemical findings, especially TTF-1 positivity and thyroglobulin negativity, are important for the diagnosis.

Thyroid-like low-grade nasopharyngeal papillary adenocarcinoma: A case report

INTRODUCTION

Thyroid-like low-grade nasopharyngeal papillary adenocarcinoma (TL-LGNPPA) is a rare neoplasm characterized by morphological analogy to papillary thyroid carcinoma and the abnormal expression of thyroid transcription factor-1 (TTF-1). We herein report a rare case of TL-LGNPPA with a review of its clinical and morphological characteristics and the treatment provided.

PATIENT CONCERNS AND DIAGNOSIS

The patient was a 50-year-old Chinese woman with the complaint of a three-year history of phlegm with blood with pharyngeal discomfort. There were no remarkable physical findings, and the laboratory tests were normal. Laryngoscopy and nasal computed tomography identified a mass at the posterior end of the nasal septum. Histologically, the tumor exhibited an oval papillary growth. Immunohistochemically, the neoplastic cells were positive for TTF-1, vimentin, cytokeratin 7, and cytokeratin 19. Pathological examination indicated a thyroid-like low-grade nasopharyngeal papillary adenocarcinoma.

INTERVENTION

The neoplasm was completely resected without any complication.

OUTCOMES

The patient had neither local recurrence nor distant metastasis 1 year after the removal of the tumor.

CONCLUSION

Although TL-LGNPPA is a malignant tumor, complete surgical resection is an effective treatment.

Clinicopathologic Characteristics of Thyroid-like Low-grade Nasopharyngeal Papillary Adenocarcinoma: A Case Report

Thyroid-like low-grade nasopharyngeal papillary adenocarcinoma (TL-LGNPPA) is an extremely rare neoplasm. It morphologically resembles papillary thyroid carcinoma and is immunochemically positive for thyroid transcription factor 1. Herein, we reported a case of TL-LGNPPA in a female patient of 35 years old. She felt pharyngeal foreign body sensation of unknown cause and subsequently developed dyspnea after activities. Nasopharyngeal plain computerized tomography showed no abnormalities, but laryngoscopy showed a peanut-sized smooth neoplasm with a pedicel at the posterior edge of the nasal septum. The mass was completely resected by nasopharyngoscopy. Histologic examination showed the tumor was composed of papillary configuration and tubular glands; each papilla was covered with cuboidal or columnar epithelial cells; tubular architecture and spindle cell component were also observed; some tumor cells had psammoma bodies. Immunohistochemically, tumor cells were positive for CKpan, CK7, CK19, VIM, and thyroid transcription factor 1, but negative for thyroglobulin, CK20, S-100, P63, P40, smooth muscle actin, CDX-2, and glial fibrillary acidic protein. This patient was diagnosed with TL-LGNPPA and followed up for 16 months, and metastasis and recurrence were not observed.

Thyroid-Like Low-Grade Nasopharyngeal Papillary Adenocarcinoma with Biphasic Histology

Thyroid-like low-grade nasopharyngeal papillary adenocarcinoma (TL-LGNPPA) is a rare primary adenocarcinoma of nasopharynx. The immunohistochemical pattern of this tumor is similar to that of papillary thyroid carcinoma making this neoplasm a challenging diagnosis. A case of TL-LGNPPA with biphasic morphology is presented. The removed tumor from the nasopharynx exhibited a polypoid appearance. Microscopically, it was composed of papillary structures admixed with a few solid areas of spindle cells. The papillae were lined by columnar epithelium. Both the epithelium and the spindle cells were strongly positive for TTF-1 and CK19 and negative for CK5/6, S-100, and thyroglobulin. Cellular atypia, necrosis, and high mitotic rate were absent. Ki67 was less than 2% in the neoplastic cells. No local recurrence or distant metastasis was reported after 12 months of follow-up. Caution should be taken to differentiate TL-LGPPA from other TTF-1-positive neoplasms, especially papillary thyroid carcinoma, as the prognosis for these two tumors is entirely different.

Thyroid-Like Low-Grade Nasopharyngeal Papillary Adenocarcinoma

OBJECTIVES

Thyroid-like low-grade nasopharyngeal papillary adenocarcinoma (TLLGNPPA) is a relatively rare nasopharyngeal tumor. We performed morphological characterization, immunohistochemical profiling, and investigated gene mutations. We also provide clinical follow-up data and brief review of the literature.

METHODS

Immunohistochemistry was used to evaluate the expression of TTF-1, CK19, CK7, EMA, TG, Pax-8, CK5/6, S100, and Ki-67. Additionally, in situ hybridization was utilized to identify the presence of EBV. We investigated mutations in hot-spot exons of KRAS/NRAS/BRAF to rule out common mutations seen in thyroid tumors.

RESULTS

Histopathologic examination of four cases identified tumors that were mainly occupied by papillary architectures. One case had a predominantly glandular structure. The tumors expressed TTF-1 and CK19, while TG and Pax-8 were negative. S100 was moderately expressed focally in three cases.

CONCLUSIONS

While TLLGNPPA displays a morphological resemblance to papillary thyroid carcinoma (PTC), it is vital to differentiate nasopharyngeal metastasis from PTC for appropriate treatment.

Thyroid-like low-grade papillary adenocarcinoma of nasopharynx

We report a 35-year-old woman with complaints of nasal obstruction and mild post-nasal drip for 6 months. She did not improve with medical treatment. Clinical examination had no positive finding. She was evaluated with a CT scan and MRI that revealed a polypoid mass lesion in nasopharynx without any adhesion to adjacent tissue. Endoscopic examination of nasopharynx revealed an exophytic nasopharyngeal mass in anterior wall of nasopharynx that complete macroscopic transnasal endoscopic resection was performed. The histopathological examination reported thyroid-like low-grade nasopharyngeal papillary adenocarcinoma that was confirmed on immunohistochemical staining. After complete macroscopic resection of the mass, patient was regularly followed-up for 6 years and there was no evidence of recurrence. This example has the educational tips of the optimal therapeutic strategies for primary nasopharyngeal adenocarcinomas with long follow-up.

Biphasic low-grade nasopharyngeal papillary adenocarcinoma: a case report and literature review

Background

Low-grade nasopharyngeal papillary adenocarcinoma (LGNPPA) is distinctly rare. We report a patient with a uniquely biphasic LGNPPA; additionally, we review similar tumors reported in the literature.

Case presentation

A 56-year-old man presented with an asymptomatic pedunculated tumor in the vault of the nasopharynx, at the junction of the nasal septum and the roof, which was discovered during screening for laryngeal cancer. To obtain a definitive diagnosis, the patient underwent endoscopic endonasal surgery under general anesthesia. Immunohistochemical analysis of the tumor revealed it to be an LGNPPA with a prominent spindle cell component.

Conclusion

To our knowledge, this is the fourth reported LGNPPA exhibiting a spindle cell component and the second with a prominent pathological condition. The prognosis of LGNPPA is usually excellent. Therefore, it is important for clinicians to scrutinize the lesion’s pathology to avoid unnecessary, disfiguring surgery.

Thyroid-Like Low-Grade Nasopharyngeal Papillary Adenocarcinoma

Thyroid-like low-grade nasopharyngeal papillary adenocarcinoma (TL-LGNPPA) is a rare entity. Patients often present with complaints of nasal fullness, obstruction, and epistaxis. It may be confused with metastatic papillary thyroid carcinoma due to its histologic similarity and overlapping immunohistochemical studies, but it is important to distinguish between the two because of differing treatment modalities and prognosis. A significant difference between the two is that despite both entities demonstrating TTF-1 positivity, TL-LGNPPA usually does not stain for thyroglobulin. TL-LGNPPA exhibits indolent growth, with no incidence of metastasis or recurrence after surgical excision.

Nasopharyngeal Papillary Adenocarcinoma as a Second Head and Neck Malignancy

Nasopharyngeal adenocarcinomas are rare tumours, and include neoplasms arising from the nasopharyngeal surface epithelium as well as those of minor salivary gland origin, each of which is distinct from the other. The former encompasses nasopharyngeal papillary adenocarcinoma (NPAC), also known as low grade NPAC and thyroid-like NPAC, an extremely unusual malignancy bearing histomorphological similarity to papillary thyroid carcinoma, and displaying indolent clinical behaviour. We report the case of a 41-year-old lady who developed NPAC as a second malignancy five-and-a-half years after being diagnosed and treated for a diffuse astrocytoma in the frontal lobe. In addition, we discuss the differential diagnosis, as well as raise certain pathogenetic considerations with regard to this unique neoplasm.