We report a case of hepatic angiomyolipoma with uncommon clinical features. A 56-year-old man presented with a hepatic tumor in the caudate lobe. The tumor was hypoechoic on ultrasonography, showed early-phase hyperat...We report a case of hepatic angiomyolipoma with uncommon clinical features. A 56-year-old man presented with a hepatic tumor in the caudate lobe. The tumor was hypoechoic on ultrasonography, showed early-phase hyperattenuation on enhanced computed tomography and did not absorb iron on superparamagnetic iron oxide-enhanced magnetic resonance imaging. Hepatocellular carcinoma was highly suspected, and the patient underwent hepatic resection. Histologically, the tumor was mainly composed of smooth muscle cells and contained small amounts of adipose cells and blood vessels. On immunohistochemical staining, the smooth muscle cells were positive for a melanocytic cell-specific monoclonal antibody. In cases with uncommon features of angiomyolipoma, it is quite difficult to distinguish angiomyolipoma from hepatocellular carcinoma.展开更多
Primary malignant melanoma originating in the colon is an extremely rare disease.Herein,we report a case of primary melanoma of the ascending colon.The patient was a 57-year-old male who was admitted to our hospital f...Primary malignant melanoma originating in the colon is an extremely rare disease.Herein,we report a case of primary melanoma of the ascending colon.The patient was a 57-year-old male who was admitted to our hospital for persistent abdominal pain and episodes of bloody stool,nausea and vomiting.A computed tomography scan revealed lower intestinal intussusception and enlarged lymph nodes in the abdominal cavity and retroperitoneum.During laparoscopic operation,multiple enlarged lymph nodes were found.Several segments of the proximal small intestine were incarcerated into the distal small intestine,forming an internal hernia and obstruction.The necrotic terminal ileum was invaginated into the ascending cecum.Subsequently,adhesive internal hernia reduction and palliative right hemicolectomy were performed.Pathologic examination of the excised specimen revealed a polypoid mass in the ascending colon.Histological examination showed epithelioid and spindle tumor cells with obvious cytoplasmic melanin deposition.Immunohistochemical staining revealed that the tumor cells were positive for S-100,HmB-45 and vimentin,confirming the diagnosis of melanoma.The patient history and a thorough postoperative investigation excluded the preexistence or coexistence of a primary lesion elsewhere in the skin,anus or oculus or at other sites.Thus,we consider our case to represent an aggressive primary colon melanoma presenting as ileocecal intussusception and intestinal obstruction.展开更多
Perivascular epithelioid cell tumor(PEComa) of the pancreas is an unusual tumor deriving from mesenchyma. This paper described a case of pancreatic PEComa, which was initially suspected as neuroendocrine carcinoma by ...Perivascular epithelioid cell tumor(PEComa) of the pancreas is an unusual tumor deriving from mesenchyma. This paper described a case of pancreatic PEComa, which was initially suspected as neuroendocrine carcinoma by biopsy, and therefore surgical treatment was recommended due to undetermined diagnosis. Examination of the surgical specimen under a microscope showed that the tumor cell's morphology was epithelioid or spindle-shaped, and ranged in a nested pattern. Additionally, these cells had a large extent of acidophilic cytoplasm, no mitotic figures, and expressed HMB-45, melan-p, and smooth muscle actin immunohistochemically. Pathological examination indicated that PEComa originated from the pancreas, but symptoms related to tuberous sclerosis were absent. Since PEComa is extremely rare in the pancreas, it is likely to be ignored in differential diagnosis. In conclusion, our article highlighted the clinicopathological features of PEComa, and we conducted a literature review focusing on PEComa so as to deepen the understanding of this tumor type.展开更多
We tested a variety of fixed embedded sections of malignant tumors with HMB-45 MoAband S-100 polyclonal antibody.The results showed that RMB-45 was a highly sensitive and specificantibody for recongnizing melanoma on ...We tested a variety of fixed embedded sections of malignant tumors with HMB-45 MoAband S-100 polyclonal antibody.The results showed that RMB-45 was a highly sensitive and specificantibody for recongnizing melanoma on fixed paraffin-embedded tissue sections, it reacted with 96.6percent of melanomas tested(all primary and 6 of 7 metastatic lesions)Both pigmented and nonpigmeated melanomas were recongnized.Malignant tumors of epithelial,lymphoid and mesenchymal origin were all negative.Although antibody to S-100 protien quite sensitive,it was not melanome-specific and it reached with all melanomas including the one metastatic melanoma that did not react withHMB-45,it we also positive in one of five lymphomas and one of three sarcomas.AdditionallyHMB-45 reacted with junctional nevi and componentes of compound neai and not with intradermalnevi and the dermal components of compound nevi.展开更多
Primary urethral malignant melanoma is an extremely rare malignancy with early metastasis and often delayed diagnosis, resulted in poor prognosis. Literature on this entity, especially with regard to urinary cytology ...Primary urethral malignant melanoma is an extremely rare malignancy with early metastasis and often delayed diagnosis, resulted in poor prognosis. Literature on this entity, especially with regard to urinary cytology is limited. We report here an extremely rare case of primary urethral malignant melanoma (MM) developed in a 95-year-old Japanese woman. A urinalysis showed macrophages containing brown granular pigments, and the urinary cytology was positive for atypical cells containing brown pigments suggestive of MM. Pathological examination of the biopsy specimen from the tumor revealed MM of the urethra. Immunohistochemically, the tumor cells showed strong cytoplasmic reactivities against antibodies, HMB-45 and Malan-A. Melanoma cells were immunohistochemically positive for c-Kit in their cytoplasm and cell membrane, although mutations in BRAF V600E and N/K-RAS were not detected. The urinary cytology and immunohistochemistry were useful for the rapid and accurate diagnosis for the urethral MM.展开更多
Monnclonal antibody HMB-45 was previously thought to be melanoma specific antibody and was taken recently as a marker for melanocyte proliferation or activation. A single UV-irradiation system which may induce a funct...Monnclonal antibody HMB-45 was previously thought to be melanoma specific antibody and was taken recently as a marker for melanocyte proliferation or activation. A single UV-irradiation system which may induce a functional activity change in melanocytes was used to test the irradiated epidermal melanocyte for expression of HMB-45.Melanocytes, in the epidermis of the biopsies taken 7 days after a single UV exposure, showed markedly stained HMB-45,accompanied by morphological changes such as enlarged size,rich cytoplasma and elongated dendrites. We conclude that since morphological changes in irradiated melanocytes may be interpreted as signs of functional activity changes, melanocytes are exposed to sthnulatory factors induced by UV light and get into a functional activating state to produce melanosome and HMB-45 antigen. Besides, the presence of HMB-45 in a single UV exposed epidermal melanocyte may support the hypothesis that its expression is inducible and is closely related to the functional activity展开更多
Pulmonary lymphangioleiomyomatosis(LAM)is a rare cystic lung disease that targets women during their reproductive years.A confident diagnosis can often be based on clinical grounds,but diagnostic certainty requires pa...Pulmonary lymphangioleiomyomatosis(LAM)is a rare cystic lung disease that targets women during their reproductive years.A confident diagnosis can often be based on clinical grounds,but diagnostic certainty requires pathological analysis.Although surgical lung biopsy is considered the gold standard for obtaining tissue in patients with diffuse lung disease,it is also associated with higher morbidity and mortality than alternative,less invasive techniques.The objective of our study was to examine the utility of transbronchial biopsy in the diagnosis of LAM.We conducted two online surveys of over 1000 LAM patients registered with the LAM Foundation who were accessible by email.Transbronchial biopsy specimens were subsequently collected and reviewed by an expert pathologist to validate the diagnosis.We found that transbronchial biopsy has a yield of approximately 60% in patients with LAM.We conclude that transbronchial biopsy may be a safe and effective method for establishing the diagnosis of LAM,obviating the need for surgical lung biopsy in more than half of LAM patients.展开更多
文摘We report a case of hepatic angiomyolipoma with uncommon clinical features. A 56-year-old man presented with a hepatic tumor in the caudate lobe. The tumor was hypoechoic on ultrasonography, showed early-phase hyperattenuation on enhanced computed tomography and did not absorb iron on superparamagnetic iron oxide-enhanced magnetic resonance imaging. Hepatocellular carcinoma was highly suspected, and the patient underwent hepatic resection. Histologically, the tumor was mainly composed of smooth muscle cells and contained small amounts of adipose cells and blood vessels. On immunohistochemical staining, the smooth muscle cells were positive for a melanocytic cell-specific monoclonal antibody. In cases with uncommon features of angiomyolipoma, it is quite difficult to distinguish angiomyolipoma from hepatocellular carcinoma.
文摘Primary malignant melanoma originating in the colon is an extremely rare disease.Herein,we report a case of primary melanoma of the ascending colon.The patient was a 57-year-old male who was admitted to our hospital for persistent abdominal pain and episodes of bloody stool,nausea and vomiting.A computed tomography scan revealed lower intestinal intussusception and enlarged lymph nodes in the abdominal cavity and retroperitoneum.During laparoscopic operation,multiple enlarged lymph nodes were found.Several segments of the proximal small intestine were incarcerated into the distal small intestine,forming an internal hernia and obstruction.The necrotic terminal ileum was invaginated into the ascending cecum.Subsequently,adhesive internal hernia reduction and palliative right hemicolectomy were performed.Pathologic examination of the excised specimen revealed a polypoid mass in the ascending colon.Histological examination showed epithelioid and spindle tumor cells with obvious cytoplasmic melanin deposition.Immunohistochemical staining revealed that the tumor cells were positive for S-100,HmB-45 and vimentin,confirming the diagnosis of melanoma.The patient history and a thorough postoperative investigation excluded the preexistence or coexistence of a primary lesion elsewhere in the skin,anus or oculus or at other sites.Thus,we consider our case to represent an aggressive primary colon melanoma presenting as ileocecal intussusception and intestinal obstruction.
文摘Perivascular epithelioid cell tumor(PEComa) of the pancreas is an unusual tumor deriving from mesenchyma. This paper described a case of pancreatic PEComa, which was initially suspected as neuroendocrine carcinoma by biopsy, and therefore surgical treatment was recommended due to undetermined diagnosis. Examination of the surgical specimen under a microscope showed that the tumor cell's morphology was epithelioid or spindle-shaped, and ranged in a nested pattern. Additionally, these cells had a large extent of acidophilic cytoplasm, no mitotic figures, and expressed HMB-45, melan-p, and smooth muscle actin immunohistochemically. Pathological examination indicated that PEComa originated from the pancreas, but symptoms related to tuberous sclerosis were absent. Since PEComa is extremely rare in the pancreas, it is likely to be ignored in differential diagnosis. In conclusion, our article highlighted the clinicopathological features of PEComa, and we conducted a literature review focusing on PEComa so as to deepen the understanding of this tumor type.
文摘We tested a variety of fixed embedded sections of malignant tumors with HMB-45 MoAband S-100 polyclonal antibody.The results showed that RMB-45 was a highly sensitive and specificantibody for recongnizing melanoma on fixed paraffin-embedded tissue sections, it reacted with 96.6percent of melanomas tested(all primary and 6 of 7 metastatic lesions)Both pigmented and nonpigmeated melanomas were recongnized.Malignant tumors of epithelial,lymphoid and mesenchymal origin were all negative.Although antibody to S-100 protien quite sensitive,it was not melanome-specific and it reached with all melanomas including the one metastatic melanoma that did not react withHMB-45,it we also positive in one of five lymphomas and one of three sarcomas.AdditionallyHMB-45 reacted with junctional nevi and componentes of compound neai and not with intradermalnevi and the dermal components of compound nevi.
文摘Primary urethral malignant melanoma is an extremely rare malignancy with early metastasis and often delayed diagnosis, resulted in poor prognosis. Literature on this entity, especially with regard to urinary cytology is limited. We report here an extremely rare case of primary urethral malignant melanoma (MM) developed in a 95-year-old Japanese woman. A urinalysis showed macrophages containing brown granular pigments, and the urinary cytology was positive for atypical cells containing brown pigments suggestive of MM. Pathological examination of the biopsy specimen from the tumor revealed MM of the urethra. Immunohistochemically, the tumor cells showed strong cytoplasmic reactivities against antibodies, HMB-45 and Malan-A. Melanoma cells were immunohistochemically positive for c-Kit in their cytoplasm and cell membrane, although mutations in BRAF V600E and N/K-RAS were not detected. The urinary cytology and immunohistochemistry were useful for the rapid and accurate diagnosis for the urethral MM.
文摘Monnclonal antibody HMB-45 was previously thought to be melanoma specific antibody and was taken recently as a marker for melanocyte proliferation or activation. A single UV-irradiation system which may induce a functional activity change in melanocytes was used to test the irradiated epidermal melanocyte for expression of HMB-45.Melanocytes, in the epidermis of the biopsies taken 7 days after a single UV exposure, showed markedly stained HMB-45,accompanied by morphological changes such as enlarged size,rich cytoplasma and elongated dendrites. We conclude that since morphological changes in irradiated melanocytes may be interpreted as signs of functional activity changes, melanocytes are exposed to sthnulatory factors induced by UV light and get into a functional activating state to produce melanosome and HMB-45 antigen. Besides, the presence of HMB-45 in a single UV exposed epidermal melanocyte may support the hypothesis that its expression is inducible and is closely related to the functional activity
文摘Pulmonary lymphangioleiomyomatosis(LAM)is a rare cystic lung disease that targets women during their reproductive years.A confident diagnosis can often be based on clinical grounds,but diagnostic certainty requires pathological analysis.Although surgical lung biopsy is considered the gold standard for obtaining tissue in patients with diffuse lung disease,it is also associated with higher morbidity and mortality than alternative,less invasive techniques.The objective of our study was to examine the utility of transbronchial biopsy in the diagnosis of LAM.We conducted two online surveys of over 1000 LAM patients registered with the LAM Foundation who were accessible by email.Transbronchial biopsy specimens were subsequently collected and reviewed by an expert pathologist to validate the diagnosis.We found that transbronchial biopsy has a yield of approximately 60% in patients with LAM.We conclude that transbronchial biopsy may be a safe and effective method for establishing the diagnosis of LAM,obviating the need for surgical lung biopsy in more than half of LAM patients.
