Odontogenic primary tumor is a rare benign odontogenic tumor in the maxillofacial area. A case of odontogenic primary basal tumor is reported. The clinicopathological features and treatment principles are discussed in the literature.
牙源性始基瘤是颌面部罕见的良性牙源性肿瘤。本文报道1例牙源性始基瘤，并结合文献探讨其临床病理特征及治疗原则。.

BACKGROUND: Salivary carcinosarcoma is an extremely rare tumor containing both malignant epithelial and mesenchymal constituents. This article reports a rare case of carcinosarcoma with salivary duct carcinoma and osteosarcoma as the tumor components. The clinicopathological characteristics, treatment, and prognosis are discussed in conjunction with the literature.
METHODS: A 48-year-old man presented with a complaint of a mass in the right parotid region. Osteosarcoma was first considered for assessment by fine-needle aspiration cytology. Physical examination revealed a mass measuring approximately 4 cm × 3.5 cm × 3 cm. The mass, the whole lobe of the right parotid gland, and the right mandible were completely removed during surgery. Postoperative histopathology confirmed carcinosarcoma of the salivary gland.
CONCLUSIONS: A definite diagnosis of salivary gland carcinosarcoma can only be obtained after complete surgical resection.

UNASSIGNED: Carcinosarcoma of the ovary is a rare pathological type of ovarian cancer that is highly aggressive and occurs most frequently in the female reproductive tract at the site of the uterus. Herein, we explore the clinicopathological features, diagnosis, differential diagnosis, and treatment options for carcinosarcoma of the ovary.
UNASSIGNED: We analyzed the clinical data of a case of carcinosarcoma, observed its histological morphology and immunohistochemical characteristics, detected the homologous recombination repair deficiency gene mutation, and reviewed the relevant literature.
UNASSIGNED: A 76-year-old menopausal woman visited our hospital because of abdominal distension, difficulty in urination, and constipation. Ultrasonography demonstrated abnormalities in the uterus and pelvic cavity, suggesting that the patient should undergo surgery. Immunohistochemical findings of carcinosarcoma of the right ovary were as follows: CK fraction (+), vimentin fraction (+), CK5/6 foci (+), p16 (+), p53 in approximately 70% (+), WT-1 foci (+), ER foci (+), PR part (+), Her-2 (1+), CK7 fraction (+), CK20 foci (+), CD99 fraction (+), CD10 fraction (+), CD56 foci (+), c-kit foci (+), SMA part (+), desmin foci (+), PD-L1 (-), SALL4 (-), OCT3/4 (-), p63 (-), p40 (-), D2-40 (-), inhibin (-), PLAP (-), CD30 (-), and Ki67 hotspot in approximately 80% (+). The patient underwent tumor cytoreduction and adjuvant chemotherapy. Currently, she is being followed up for 16 months and has a good general condition.
UNASSIGNED: The diagnosis of carcinosarcoma relies on histopathological examination and differentiation of carcinosarcoma from immature teratoma. The current therapeutic regimen for carcinosarcoma is still based on tumor cytoreduction and platinum-containing chemotherapy; research on targeted therapy is still in progress.

Pleomorphic undifferentiated sarcoma (PUS) of the mediastinal thymus is a rare type of cancer. In the present case report, a 67-year-old female patient presenting a mediastinal mass for >1 year was assessed for clinical characteristics, histopathological, immunohistochemical expression and gene mutation using fluorescence in situ hybridization (FISH), and relevant literature was reviewed. Histological analysis revealed nodular changes of different sizes in the thymus, which consisted of a mixture of pleomorphic and spindle cells. The pleomorphic cells with distinct atypia were giant cells and multinucleated cells with large cell sizes and frequent nuclear divisions. The spindle cells were mild to moderate atypical and arranged in a woven pattern, and nuclear division was rare. Immunohistochemical analysis indicated that vimentin was diffusively expressed in tumor cells. No amplification was found in CDX2 and MDM4 genes using the FISH analysis. In conclusion, mediastinal thymus neoplasm should be considered in the presence of PUS and it is an exclusionary diagnosis based on clinical and pathological examination of the patient.

Primary cutaneous anaplastic large cell lymphoma is a rare non-Hodgkin\'s lymphoma.The tumor cells have the characteristics of anaplastic cells,expressing CD30 but not anaplastic lymphoma kinase.In this study,we reported a case of primary cutaneous anaplastic large cell lymphoma in a Tibetan child and summarized the clinicopathological features,aiming to strengthen the understanding of this disease.

Myofibroblastoma is a rare type of benign myofibroblastic neoplasm in the breast. It is clinically presented as a well-circumscribed mass, usually small in size (usually less than 4.0 cm), and can mostly be cured by local excision. Rare cases of giant myofibroblastoma greater than 10 cm have been reported, but also follow a benign clinical course. Histologically, breast myofibroblastoma is featured by bland fascicles of spindle cells intermixed with thick hyalinized collagen bundles. Mast cells are frequently found within the stroma. However, a wide spectrum of morphological variants can occur in myofibroblatoma, making its diagnosis challenging sometimes. Differential diagnosis of myofibroblastoma with other spindle cell lesions in the breast, either benign or malignant, is also important in practice. In this study, we collected 15 cases of breast myofibroblastoma diagnosed in our institution during a 20 year period. The sizes of these cases range from 0.4 cm to 35.2 cm (mean is 3.7 cm). To our knowledge, the case of giant breast myofibroblastoma we presented here is the largest one reported to date. The histological examination of the cases show great morphological variations. Besides the classical type, features of cellular, collagenized, palisading, epithelioid, myxoid, myoid, solitary fibrous tumor-like are also identified in the case series. Immunohistochemical staining patterns as well as clinical features of the cases are also summarized and compared. All cases in this study show no recurrence on follow-up. In addition, cases that are important differential diagnosis for breast myofibroblastoma are also studied. Their key histological characteristics are compared with myofibroblastoma, and their immunohistochemical and molecular features are discussed.

The following fictional case is intended as a learning tool within the Pathology Competencies for Medical Education (PCME), a set of national standards for teaching pathology. These are divided into three basic competencies: Disease Mechanisms and Processes, Organ System Pathology, and Diagnostic Medicine and Therapeutic Pathology. For additional information, and a full list of learning objectives for all three competencies, see http://journals.sagepub.com/doi/10.1177/2374289517715040.1.

Langerhans cell histiocytosis is commonly found in cranial bones and rarely found in the mandible. This article presents a case of mandibular Langerhans cell histiocytosis and discusses its pathogeny, clinical features, diagnosis, and treatment.
朗格汉斯细胞组织细胞增生症在临床上以颅骨多见，较少发生于下颌骨。本文报道1例下颌骨朗格汉斯细胞组织细胞增生症，并结合文献探讨朗格汉斯细胞组织细胞增生症的病因、临床病理表现、诊断及治疗。.

BACKGROUND: The pathogenesis of a ciliated muconodular papillary tumor (CMPT) of the lung is extremely rare which is difficult to distinguish from other lung lesions and it is easy to cause misdiagnosis and missed diagnosis. By collecting CMPT data, its clinical and pathological features can provide medical treatment ideas for the majority of medical workers and reduce medical errors.
METHODS: The clinical data, pathological features, immunophenotype of a typical CMPT patient and related literature were analyzed.
RESULTS: The chest computed tomography (CT) showed there was a mixed density nodule in the right lower lung near the pleura with a diameter of about 9 mm. We performed a wedge resection on the patient. The pathological results showed that the nodule was composed of proliferated ciliated cells, mucous cells, and basal-like cells. The ciliated cells were lined on the surface of papillary structures. The basal-like cells were located in the outer layer, while the mucous cells were located between the two. The cell atypia was not obvious. Immunohistochemistry: epithelial cells CEA (+), CK7 (+), CA125 (+), weakly positive for TTF-1, CK20 (-), Ki67 (1%+), CK5/6 (+), and basal cells P63 (+).
CONCLUSIONS: CMPT is a rare pulmonary neoplasm. There is no definite conclusion about its biologic nature, but most experts prefer a benign to a malignant tumor. CMPT can show many malignant tumor signs on imaging and is often mistaken for lung adenocarcinoma. According to its typical histopathological characteristics and immunohistochemical phenotype, it can be differentiated from other pulmonary diseases. Whether gene mutation is the driving factor is still unknown. Surgical resection for the tumor reveals a good prognosis.
【中文题目：典型肺纤毛黏液结节性乳头状肿瘤1例 临床病理分析】 【中文摘要：背景与目的 肺纤毛黏液结节性乳头状肿瘤（ciliated muconodular papillary tumor of the lung, CMPT）的发病极其少见，在临床上与其他肺部病变亦难以区别，易造成误诊、漏诊；通过收集CMPT的资料，分析其临床病理特征，可以为广大医务工作者提供诊治思路，减少医疗差错。方法 回顾性分析1例典型的CMPT患者的临床资料、病理特征、免疫表型并结合相关文献进行探讨。结果 患者胸部计算机断层扫描（computed tomography, CT）提示右下肺近胸膜处可见混合密度结节影，直径约9 mm，肿瘤行肺楔形切除术，镜下见结节由增生的纤毛细胞、黏液细胞及基底样细胞混合组成，以乳头状、腺样结构为主，纤毛细胞衬覆于乳头状结构表面，基底样细胞位于外层，黏液细胞则位于两者之间，各种细胞异型不明显。免疫组化：上皮细胞CEA（+）、CK7（+）、CA125（+）、TTF-1（弱+）、CK20（-）、Ki67（1%+）、CK5/6（+）；基底细胞P63（+）。结论 CMPT是一种新近发现的罕见的肺部肿瘤，关于其良恶性目前尚无定论，但多数学者倾向于良性，其在影像学上可表现出诸多恶性肿瘤征象而常被误认为是肺腺癌，通过其典型的病理组织学特点及免疫组化表型可与其他肺部疾病进行鉴别，基因突变是否是其驱动因素目前尚不得知，该肿瘤行手术切除预后较好。】 【中文关键词：肺肿瘤；肺纤毛黏液结节性乳头状肿瘤；临床病理学；免疫表型】.

BACKGROUND: Castleman disease (CD) is a rare lymphoproliferative disorder that presents with various symptoms. CD accompanied with jaundice is uncommon since there are only 11 cases reported in the literature.
METHODS: Here we report a 62-year-old woman who was admitted to the hospital with signs and symptoms of intermittent jaundice. Biochemical tests showed higher serum levels of total and direct bilirubin, and normal serum levels of tumor markers and interleukin-6. Contrast-enhanced computed tomography detected a 6 cm × 4 cm × 2.5 cm mass between the hepatoduodenal ligament and the inferior vena cava. The mass was successfully excised and the patient had a complete resolution of symptoms. A diagnosis of idiopathic unicentric CD was made based upon histological examination, which demonstrated the pathological features of CD of mixed type, including hyperplasia of follicular lymphoids with abundant plasma cells, degenerative germinal centers, interfollicular vascularity and hyaline degeneration. The diagnosis was corroborated by immunohistochemical analysis which detected multiple biomarkers.
CONCLUSIONS: This is the first study that describes the clinicopathological features of CD presenting with jaundice, which may deepen and extend our understanding of this disease.