Neuroendocrine tumors of the urinary bladder - Report of two cases.

Primary paraganglioma and small cell neuroendocrine carcinoma of the urinary bladder are rare tumors, comprising 0.05% of all bladder tumors and <1% of all malignant bladder tumors, respectively. These tumors can be the cause of a diagnostic dilemma or misdiagnosis on morphology. Paraganglioma is often mistaken for urothelial carcinoma and small cell carcinoma for poorly differentiated carcinoma or lymphoma. Herein, we report a case of primary paraganglioma and another of a small cell carcinoma of the urinary bladder and discuss their closest differential diagnoses. The diagnostic pitfalls should be kept in mind so that correct, timely diagnosis of these entities can be made due to implications in the management and prognosis.

Villous adenoma of the renal pelvis: a common entity at an uncommon location.

Villous adenoma is uncommonly seen in the urogenital tract and is even more rarely seen in the upper urinary tract and renal pelvis. Like colorectal adenomas, these neoplasms can transform into adenocarcinoma. The preoperative diagnosis is challenging due to their frequent association with hydronephrosis. Herein, we present the case of a villous adenoma of the renal pelvis in a 62-year-old man presenting with recurrent urinary tract infection. The computed tomography scan showed marked hydronephrosis but no suspicious mass in the right kidney. A laparoscopic right nephrectomy was performed. Gross examination revealed a dilated renal pelvis with an irregular exophytic lesion in the renal pelvis's upper surface. The histopathological examination showed slender, elongated villi with thin fibrovascular cores, consistent with villous adenoma morphology. Isolated villous adenomas have a favorable prognosis. However, the pathologist should undertake a search for an invasive component.

Neuroendocrine tumors of the urinary bladder - Report of two cases

Primary paraganglioma and small cell neuroendocrine carcinoma of the urinary bladder are rare tumors, comprising 0.05% of all bladder tumors and <1% of all malignant bladder tumors, respectively. These tumors can be the cause of a diagnostic dilemma or misdiagnosis on morphology. Paraganglioma is often mistaken for urothelial carcinoma and small cell carcinoma for poorly differentiated carcinoma or lymphoma. Herein, we report a case of primary paraganglioma and another of a small cell carcinoma of the urinary bladder and discuss their closest differential diagnoses. The diagnostic pitfalls should be kept in mind so that correct, timely diagnosis of these entities can be made due to implications in the management and prognosis.

Villous adenoma of the renal pelvis: a common entity at an uncommon location

Villous adenoma is uncommonly seen in the urogenital tract and is even more rarely seen in the upper urinary tract and renal pelvis. Like colorectal adenomas, these neoplasms can transform into adenocarcinoma. The preoperative diagnosis is challenging due to their frequent association with hydronephrosis. Herein, we present the case of a villous adenoma of the renal pelvis in a 62-year-old man presenting with recurrent urinary tract infection. The computed tomography scan showed marked hydronephrosis but no suspicious mass in the right kidney. A laparoscopic right nephrectomy was performed. Gross examination revealed a dilated renal pelvis with an irregular exophytic lesion in the renal pelvis's upper surface. The histopathological examination showed slender, elongated villi with thin fibrovascular cores, consistent with villous adenoma morphology. Isolated villous adenomas have a favorable prognosis. However, the pathologist should undertake a search for an invasive component.

Epithelioid angiomyolipoma with tumor thrombus in IVC and right atrium.

Epithelioid angiomyolipoma is an uncommon subtype of renal angiomyolipoma associated with potentially malignant behavior and is considered a distinct entity by the World Health Organization classification of renal tumors. We present a case of an epithelioid variant of angiomyolipoma with extension into the renal vein, inferior vena cava reaching up to the right atrium. Pre-operatively, a diagnosis of renal cell carcinoma was considered based on imaging findings. Intra-operatively due to extensive adhesions, surgical resection was not performed and only tissue sampling was performed for histopathology. Microscopic examination revealed short fascicles of spindle cells and perivascular epithelioid cells. A differential diagnosis of renal cell carcinoma with sarcomatoid differentiation was considered. The immunohistochemical profile showed tumor cells that express Melan-A and smooth muscle actin, while they were negative for pan-cytokeratin, PAX8, CK7, CD117 and CD34. Therefore a diagnosis of epithelioid angiomyolipoma was rendered. The presence of intravascular thrombi on radiological investigation and carcinoma-like growth pattern on light microscopy may compound an erroneous diagnosis of renal cell carcinoma. Hence, it is prudent for the urologist to consider differential diagnosis other than renal cell carcinoma when confronted with a renal neoplasm presenting with intravascular thrombi. In these cases, a core biopsy should be planned pre-operatively and diagnosis should be made with aid of appropriate immunohistochemical markers.

Epithelioid angiomyolipoma with tumor thrombus in IVC and right atrium

Epithelioid angiomyolipoma is an uncommon subtype of renal angiomyolipoma associated with potentially malignant behavior and is considered a distinct entity by the World Health Organization classification of renal tumors. We present a case of an epithelioid variant of angiomyolipoma with extension into the renal vein, inferior vena cava reaching up to the right atrium. Pre-operatively, a diagnosis of renal cell carcinoma was considered based on imaging findings. Intra-operatively due to extensive adhesions, surgical resection was not performed and only tissue sampling was performed for histopathology. Microscopic examination revealed short fascicles of spindle cells and perivascular epithelioid cells. A differential diagnosis of renal cell carcinoma with sarcomatoid differentiation was considered. The immunohistochemical profile showed tumor cells that express Melan-A and smooth muscle actin, while they were negative for pan-cytokeratin, PAX8, CK7, CD117 and CD34. Therefore a diagnosis of epithelioid angiomyolipoma was rendered. The presence of intravascular thrombi on radiological investigation and carcinoma-like growth pattern on light microscopy may compound an erroneous diagnosis of renal cell carcinoma. Hence, it is prudent for the urologist to consider differential diagnosis other than renal cell carcinoma when confronted with a renal neoplasm presenting with intravascular thrombi. In these cases, a core biopsy should be planned pre-operatively and diagnosis should be made with aid of appropriate immunohistochemical markers.

Liposome and Their Applications in Cancer Therapy

ABSTRACT Liposomes, the vesicles of phospholipid bilayer, can encapsulate both hydrophilic and lipophilic drugs and protect them from degradation. Liposomes have been extensively studied and continue to create intense interest in research since their discovery in the mid-1960s. Since then, liposomes have been considered to be the most successful nanocarriers for drug deliver and have made their way to the market. Currently, a number of liposomal formulations are on the marker for cancer treatment and many more are in pipe line. This review discusses about the liposome components, methods of preparation, drug encapsulation mechanism and the potential therapeutic applications of liposomes in cancer therapy.