Sclerosing mucoepidermoid carcinoma with eosinophilia of thyroid gland in a male patient: a case report and literature review

Sclerosing mucoepidermoid carcinoma with eosinophilia (SMECE) was first described by Chan et al in 1991. It is characterized by nest or strands of epidermoid tumor cells with squamous differentiation, rare mucous cells, prominent sclerotic stroma, eosinophilic and lymphoplasmacytic infiltration, and a background of chronic lymphocytic thyroiditis in the non-neoplastic thyroid gland. It is important to recognize SMECE of thyroid and differentiate it from squamous cell carcinoma or other neoplasms with squamous differentiation/metaplasia. In published cases, the SMECE of thyroid gland predominantly occurs in women. We report a case of SMECE of thyroid in a 45-year-old male patient. All cases in male patients were Caucasian described in English literature, and our case is the first one in Asian.     

Sclerosing mucoepidermoid carcinoma with eosinophilia of the salivary glands

We encountered two cases of low malignant mucoepidermoid carcinoma with scanty cellular atypism which originated in the parotid or submandibular gland and was characterized by marked fibrosis and eosinophilic infiltration within tumor tissue despite the predominance of the squamous component. Here we report these two cases and provide a review of the literature. We believe that clinically these two tumors with stromal fibrosis and eosinophilic infiltration have a low malignant potential, although histological examination revealed a scanty mucus-producing epithelial component. Therefore, we consider this type of tumor as a new subtype of mucoepidermoid carcinoma. A low-malignant mucoepidermoid carcinoma with stromal fibrosis and eosinophilic infiltration, as described in these two cases, may be misdiagnosed as a highly malignant mucoepidermoid carcinoma or squamous cell carcinoma because of its histologically scanty mucus-producing epithelial component. The objective of this study was to clarify their differences and to discuss the rendering of an accurate histological diagnosis, the degree of malignancy in relation to prognosis prediction, and the choice of therapy. In addition, we propose regarding this type of tumor as a new subtype of mucoepidermoid carcinoma.     

Cytologic features in fine-needle aspirates from a sclerosing mucoepidermoid thyroid carcinoma with eosinophilia

Fine-needle aspirates from a sclerosing mucoepidermoid thyroid carcinoma with eosinophilia showed peculiar but nonspecific features. The overall picture seems more important than individual elements in recognizing this rare entity cytologically, since the predominant type of malignant cells has a deceptively bland appearance. The differential diagnoses include other primary thyroid malignancies, as well as metastatic growth and Hashimoto's thyroiditis. Diagn Cytopathol 1996;15:301–305. © 1996 Wiley-Liss, Inc.     

Sclerosing mucoepidermoid carcinoma with eosinophilia of the thyroid

Sclerosing mucoepidermoid carcinoma with eosinophilia (SMECE) is a recently described carcinoma of the thyroid gland associated with Hashimoto's thyroiditis and considered to have a relatively indolent clinical course. We present a 65-year-old female, clinically euthyroid, who presented with a thyroid swelling since last 8 months along with right-sided cervical lymphadenopathy. Fine needle aspiration cytology suggested poorly differentiated carcinoma along with the involvement of the lymphnodes while histopathological examination showed features of SMECE with metastatic deposits in the right-sided cervical lymphnodes.     

Mucoepidermoid carcinoma of the thyroid

Clinical and morphological features of three cases of primary mucoepidermoid carcinoma of the thyroid are described. The tumours were composed of two cell types. One of these resembled squamous epithelium and ultrastructurally showed tonofilaments and numerous desmosomes. The other cell type contained Alcian blue and mucicarmine positive mucin and, on electron microscopy, showed mucigen granules. Marked stromal fibrosis and psammoma bodies were seen in all tumours. Immunohistochemical studies showed that the tumour cells were negative for thyroglobulin. A few calcitonin-containing cells were seen in one metastatic tumour. One tumour showed, in addition to the histological features of mucoepidermoid carcinoma, anaplastic areas with obvious transition between the two histological patterns. The same thyroid also had a small thyroglobulin-positive papillary carcinoma in the opposite lobe. All tumours presented lymph node metastases. In two cases the primary tumour was confined within the thyroid capsule but that with anaplastic areas invaded surrounding structures. This patient died 13 months after diagnosis; the other patients are alive and symptomless one and 10 years since diagnosis. Mucoepidermoid carcinoma of the thyroid appears to be a clinicopathological entity that resembles papillary carcinoma in its natural history. The origin of the tumour is unclear. There is, however, some histological and immunohistological data suggesting that the tumour might be related to the ultimobranchial system although some histological features also appear to favour a common origin with papillary carcinoma.     

Sclerosing mucoepidermoid carcinoma with eosinophilia of the thyroid--a case report

We report a 55-year old female who presented with thyroid swelling for six months. She was clinically asymptomatic with normal thyroid functions. Thyroidectomy revealed the left lobe totally replaced by a well-circumscribed grey white homogenous tumor. Microscopically, the tumor comprised of cells arranged in adenoid pattern along with nests of cohesive intermediate cells, some also forming keratin pearls in a sclerotic and inflammatory background. The thin rim of thyroid at the periphery showed features of lymphocytic thyroiditis. No other associated malignancy was seen on thorough screening. The tumor cells were negative for thyroglobulin and calcitonin. The patient was thus diagnosed with Sclerosing mucoepidermoid carcinoma with eosinophilia, thyroid.     

Sclerosing mucoepidermoid carcinoma with eosinophilia of the thyroid: description of a case]

INTRODUCTION: A case of sclerosing mucoepidermoid carcinoma with eosinophilia of the thyroid gland is described. RESULTS: The patient, a 32 year-old female with Hashimoto's thyroiditis, presented with a 4 cm nodule of the right lobe of the thyroid gland. The tumour was constituted by squamoid cords infiltrating a dense fibro-jaline stroma rich in eosinophils. The patient is alive and well 14 months after surgery. DISCUSSION: The literature is briefly reviewed and the differential diagnosis is discussed. In the Author's opinion, sclerosing mucoepidermoid carcinoma with eosinophilia of the tyroid is a well defined clinicopathological entity.     

Sclerosing mucoepidermoid tumour of the parotid gland: report of a case

A case of a low-grade mucoepidermoid tumour showing an unusual pattern of extensive central keloid-like sclerosis is reported. The sparsity of tumour islands renders recognition of its neoplastic nature difficult. It is postulated that the sclerosis results from exaggerated post-inflammatory scarring due to extravasation of mucin from the tumour into the stroma.     

Occult thyroid carcinoma: a rare case report and review of literature

Occult thyroid carcinoma is very common in the clinic and is generally divided into four groups. Here, we proposed two types of occult thyroid carcinoma as the fifth group. The first type was locoregional lymph node metastases from thyroid carcinoma, and the second type was distant organ metastases from thyroid carcinoma. The unique aspect of the fifth group was that the primary carcinoma of the fifth group was not finally found by pathological examination. To better understand the fifth group, we reported a typical case. Furthermore, we discussed the diagnostic criteria and procedures and the management of the fifth group of occult thyroid carcinoma.     

High-grade mucoepidermoid carcinoma of the breast

A case of high-grade mucoepidermoid carcinoma of the breast with a dominantly epidermoid component is presented. The tumour was biochemically oestrogen and progesterone receptor negative. Though the primary tumour was small (1 cm) and without axillary lymph node metastases at mastectomy, the clinical course was rapid. Despite radio-, chemo- and hormonal therapy the patient died 25 months after mastectomy with widespread systemic disease. The metastatic pattern was that of typical breast carcinoma despite the unusual histological appearance of both primary and metastatic tumour tissue.     

Breast mucoepidermoid carcinoma: a case report and review of literature

Breast mucoepidermoid carcinoma (MEC) is clinically rare, with an estimated incidence of 0.2-0.3% of all primary breast tumors. To date, only 41 cases have been reported in the literature. Herein, we present a case of breast MEC diagnosed at our hospital. The clinicopathologic features were preliminarily discussed by reviewing the literature. A 42-year-old Chinese woman presented with a lump in her right breast that was detected approximately three months prior. A microscopic examination showed that the breast MEC was composed of different proportions of mucinous cells, intermediate cells, and epidermoid cells. Most mucinous cells were positive for cytokeratin 7, while the epidermoid and intermediate cells were positive for p63 and cytokeratin 5/6. All tumor cells were negative for other myoepithelial markers, such as calponin. Tumor cells did not express estrogen, progesterone, or the HER-2/neu protein. After the patient underwent mastectomy, she was diagnosed with a low-grade mucoepidermoid carcinoma based on the clinical, histologic, and immuno-phenotypic characteristics. Our findings provide further insight into the pathologic mechanism of MEC, as correct diagnosis is essential for patient management.     

A study on the relationship between solid cell nests and mucoepidermoid carcinoma of the thyroid

Mucoepidermoid carcinoma of the thyroid (MECT) has been recently recognized as a pathological entity. The origin of MECT is unknown but the morphology of this tumour closely resembles features seen in the ultimobranchial body (UB) vestiges. Recent studies in man have shown strong evidence that the so-called solid cell nests (SCN) of the thyroid may correspond to the human UB vestiges. To investigate whether these vestiges are the site of origin of this tumour a comparative study on SCN and MECT was undertaken. One hundred autopsied thyroids cut at 2-3 mm intervals were studied for the presence of SCN. Histochemical (H & E, Alcian blue-PAS, Mayer mucicarmine) and immunohistochemical studies (calcitonin, epidermal keratin) were performed in SCN and four cases of MECT. Sixty percent of thyroids were found to have SCN. They were mainly composed of epidermoid-like cells arranged in solid structures or lining cystic cavities, tubular and follicular structures. Solid clusters usually showed lumina containing PAS-positive and mucin-positive cell debris. Mucin stains also revealed mucinous cells placed around lumina filled by mucosubstances. Characteristic PAS-positive rounded bodies were found filling lumina as well as within some apical epidermoid-like cells, mucinous cells and cell debris. An obvious transition between these cells, cell debris and mucosubstances filling the lumina was noticed; suggesting degenerative changes undergone by the epidermoid-like cell. MECT basically presented all histological and histochemical features shown by SCN, furthermore, calcitonin containing cells were observed in 54% of SCN, while a metastatic MECT also showed scattered C cells within solid islands. The presence of epidermal keratin in all SCN and MECT, together with the previous findings, are strong evidence that MECT could originate in the SCN or human UB vestiges.     

Primary mucoepidermoid carcinoma and sclerosing mucoepidermoid carcinoma with eosinophilia of the thyroid gland: a report of nine cases.

Mucoepidermoid carcinoma is a rare primary thyroid tumor with indolent biologic potential. Two types of tumors have been described under this category: mucoepidermoid carcinoma (MEC) and sclerosing mucoepidermoid carcinoma with eosinophilia (SMECE). The MEC shows both squamous and glandular differentiation in a background of a noninflamed gland, whereas SMECE is characterized by extensive sclerosis, squamous and glandular differentiation, a concomitant inflammatory infiltrate rich in eosinophils, and a background of lymphocytic thyroiditis. We present nine cases of these entities: five MEC and four SMECE. All tumors occurred in women (age 27 to 73 years). Five tumors showed extrathyroidal invasion and multiple lymph node metastases. One case of MEC showed a concomitant tall cell variant of papillary carcinoma with vascular invasion, and two cases showed intimately associated areas of usual papillary carcinoma. One of the latter cases also showed areas of transformation to anaplastic carcinoma. In all cases of SMECE and in only one case of MEC, the uninvolved thyroid tissue showed lymphocytic thyroiditis. Follow-up information was available in four of the nine cases (3 months to 7 years). Two patients with SMECE are alive with no evidence of disease. One patient with MEC and tall cell variant of papillary carcinoma died of disease after 3 months, and the patient with anaplastic carcinoma died after 5 months with lung metastasis. Both MEC and SMECE were positive for cytokeratin and negative for calcitonin. All cases of MEC were positive for thyroglobulin, whereas all cases of SMECE were negative. The immunohistochemical findings suggest that both MEC and SMECE have different histogenesis.     

肺黏液表皮样癌的分子特征

目的:探讨肺黏液表皮样癌的分子特征.方法:回顾性对2013年7月至2016年12月13例病理确诊并接受治疗的肺黏液表皮样癌临床特征和分子特点进行分析.结果:EGFR基因突变率为15.38%(2/13),且2例均为L861Q点突变,EGFR基因状态与性别(P=1.000)、年龄(P=1.000)、吸烟史(P=0.848)及分期(P=1.000)均无相关性;MAML2融合基因阳性率为45.45%(5/11),MAML2融合基因状态与性别(P=0.521)、年龄(P=0.521)、吸烟史(P=1.000)及分期(P=0.924)均无相关性(P>0.05).结论:肺黏液表皮样癌中EGFR基因最常见的突变为L861Q,EGFR基因野生型患者中存在MALM2基因融合.     

Adenoid cystic carcinoma of the right main bronchus showing squamous differentiation and mimicking mucoepidermoid carcinoma: a case report

Complete dissection of tracheobronchial adenoid cystic carcinoma (TACC) by surgery alone is sometimes difficult and has a greater propensity than tracheobronchial mucoepidermoid carcinoma (TMEC) for its surgical margin to become positive. In addition, TACC is more likely to present distant metastases than TMEC. Considering these facts, TACC and TMEC should be differentiated based on histopathological examination of biopsy specimens. Herein, we present a case of 54-year-old woman with a tumor in the right main bronchus, whose biopsy specimen was difficult to diagnose as TACC or TMEC. The specimen from the rounded protrusion of the tumor showed squamous differentiation, along with the presence of glandular and basaloid cells, making morphological examination alone ineffective in rendering a definite diagnosis. Thus, the addition of immunohistochemical analysis, αSMA and CD43 expression in basaloid cells and c-kit expression in glandular cells, was useful for accurately diagnosing TACC in this case. The squamous component was considered to be neoplastic because of its increased expression of cyclin D1 and overexpression of p16. The surgically resected specimen contained typical morphology of ACC, and the diagnosis of TACC was definitely confirmed.     

Papillary thyroid carcinoma metastatic to the pancreas: Case report

Papillary thyroid carcinoma (PTC) is generally associated with an excellent long‐term outcome. Distant metastasis is rare with only 5‐7% of patients developing distant disease. Metastasis of PTC to the pancreas is an exceedingly rare occurrence. To date, few cases have been reported. We present the case of an 81‐year‐old man with past medical history of PTC status post total thyroidectomy with local recurrence treated with radioactive iodine and selective neck dissection. Ten years after his initial diagnosis, PET‐CT scan revealed a new hypermetabolic 1.1 cm × 0.9 cm left lower lobe lung nodule and hypermetabolism in the proximal body of the pancreas. Follow‐up MRI cholangiogram showed a 1.0 × 0.8 cm T1 hypointense lesion in the proximal body of the pancreas. Endoscopic ultrasound‐guided fine‐needle aspiration biopsy of the pancreatic mass showed neoplastic epithelial cells arranged in papillary clusters with fibrovascular cores and syncytial sheets with high nuclear to cytoplasmic ratio, visible nucleoli, nuclear pallor, focal nuclear grooves, and rare intranuclear pseudoinclusions. Immunohistochemical stains performed on the smears showed positive nuclear expression of TTF‐1 and PAX‐8. The findings were consistent with metastatic PTC. Surgical resection of the lung nodule confirmed metastatic PTC. Pancreatic metastases usually occur after long time intervals with reports of up to 8 years in PTC. This makes the diagnosis more challenging, and metastatic disease should always be in the differential diagnosis in cases presenting with a pancreatic mass, especially in patients with a prior malignancy.