Abstract. Urothelial cancer is the most frequently diagnosed type of malignant tumor in the bladder, of which primary adenocarcinoma accounts for a small percentage. Secondary malignancies, in particular metastatic adenocarcinoma from the lung, are exceedingly rare, with only six cases previously reported in the literature. The present study describes the case of a 71-year-old Chinese male patient with known lung cancer for >2 years, who was diagnosed with metastatic adenocarcinoma to the bladder. The histopathological characteristics and immunohistochemical features of the patient are reported. It was proposed that pathologists should consider the possibility of metastatic adenocarcinoma from the lung, rather than assume a diagnosis of primary adenocarcinoma of the bladder or direct invasion of adenocarcinoma from the surrounding organs. Furthermore, it is essential to determine the medical history of each patient and observe the immunohistochemical features of all tumors prior to diagnosis. IntroductionBladder cancer is the fifth most common type of malignant tumor. Among bladder malignancies, urothelial carcinomas are the most frequent histological type, of which adenocarcinoma, squamous cell cancer and small-cell cancer account for small percentages (1,2). Primary adenocarcinomas were reported to account for 0.5-2% of primary bladder epithelial malignancies; these malignancies most commonly arise in the urachus (3).In addition, secondary adenocarcinomas may also occur as a result of direct invasion from the surrounding organs, including prostate, colorectal and cervical sites (3). Furthermore, metastatic spread may occur via lymphogenous or hematogenous routes (4). However, the bladder is not a favored site for tumor metastases; in particular, adenocarcinoma from the lung is exceptionally rare (5). The present study describes a case of metastatic adenocarcinoma from the lung to the bladder and reports the histopathological characteristics and immunohistochemical features of the patient. The aim of the present study was to emphasize the importance of considering of metastatic adenocarcinoma from the lung as a possible diagnosis, in addition to primary adenocarcinoma and direct invasion of adenocarcinoma from the immediate surrounding organs. Case reportA 71-year-old Chinese male with known lung cancer for >2 years was referred to the People's Liberation Army 205 Hospital (Jinzhou, China) due to a gross hematuria, which had persisted for 5 days. This initial diagnosis of lung adenocarcinoma occurred >2 years previously, when the patient was admitted to a local hospital due to a cough and expectoration. Following the initial admission to hospital, a thoracic computed tomography (CT) revealed a 3x2x2 cm mass in the lower lobe of the patient's left lung; consequently, a needle biopsy was performed and the patient was diagnosed with adenocarcinoma of the lung (histological sections were not available for review). The patient elected not to undergo any therapy, including surgical resection, chemical therapy or radi...

Abstract. Liposarcoma has previously been described in Western studies, however, such cases are rarely reported in the mediastinum. In addition, the presence of a liposarcoma with smooth muscle and neural differentiation has not been previously reported. Thus, the present study describes the rare case of a 28-year-old Chinese male admitted to our hospital with the symptoms of chest tightness and shortness of breath due to a recurrent fibrolipoma in the mediastinum. The resected tumor measured 23 cm at its largest diameter, with histopathological and immunohistochemical features indicating a well-differentiated liposarcoma accompanied by smooth muscle and neural differentiation. Following the resection, the patient underwent radiation treatment and remains alive with no evidence of disease recurrence at two months post-surgery. To the best of our knowledge, the present study is the first to report a case of liposarcoma with smooth muscle and neural differentiation, which indicates that liposarcomas could potentially originate from stem cells. The present study highlights the fact that pathologists must carefully investigate the histopathological characteristics of liposarcomas in order to obtain an accurate diagnosis.