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Mika Watanabe

Publications and source records attributed to Mika Watanabe.

53 records · Page 3Linked to original sources
PubMed2004

Scrotum-like protrusion of lipoma arising from the proximal thigh--report of two cases.

We report two cases of large lipomas arising from the proximal thigh with an extremely uncommon shape. The tumors were elastic soft and movable. MRI examination revealed both tumors with high signal intensity as fatty tissue on both T1 and T2-weighted images. Needle biopsy of the specimens revealed lipoma. Marginal excision was carried out for both cases because of the patients' discomfort. No recurrence was found three and five years after surgery, respectively.

Humans↗
PubMed2004

Super bone scan due to bone marrow metastases appearing 19 years after surgery for early gastric cancer--a case report.

A 54 year old man presenting a so-called super bone scan is reported. The patient had a past history of subtotal gastrectomy due to early gastric cancer 19 years previously. Laboratory data indicated microcytic anemia and high serum alkaline phosphatase. Both the serum calcium and phosphate levels were within normal ranges. In spite of extensive examination for a primary malignant lesion in the organs including the remaining stomach, no solid tumors were identified. Pathological examinations revealed that the tumor cells in the biopsy specimen from the lumbar spine were almost identical to those in the gastric cancer excised 19 years previously. We considered that micrometastases in the bone marrow existed at the time of the initial surgery for gastric cancer and reappeared 19 years later showing super bone scan.

Adenocarcinoma↗
PubMed2003

Endocervical-like mucinous borderline tumors of the ovary: clinicopathological features and electron microscopic findings.

Endocervical-like mucinous borderline tumor (EMBT) is a distinct entity of the ovary that seems to be underrecognized. It occurs with relatively high frequency in Japanese women. Compared with intestinal-type mucinous borderline tumor (IMBT), more frequent bilateral occurrence, paucilocular cysts, association with endometriosis, absence of pseudomyxoma but possible association of peritoneal implants and lymph node metastases, and lower mortality rate are the characteristic features. Histologically, it consists of a mixture of two types of epithelium, tall columnar mucinous cells and stratified eosinophilic cells. Electron microscopy revealed that they were endocervical glandlike mucinous cells and ciliated columnar epithelium reminiscent of the fallopian tube. As the mixture of EMBT and serous borderline tumor (seromucinous borderline tumor) occurs, these findings may show that the tumor shows MUllerian origin with two-way differentiation, or differentiation toward endocervical glands with metaplastic features as seen in reactive endocervical lesions.

Adenocarcinoma, Mucinous↗
PubMed2003

Epithelioid sarcomas with elevated serum CA125: report of two cases.

Epithelioid sarcoma (ES) is a musculoskeletal malignant tumor with epithelioid appearance. It is a relatively rare soft tissue neoplasm, the histological diagnosis of which is difficult and the histogenesis is still obscure. Like many other musculoskeletal tumors, according to the literature, ES has no useful tumor marker to be monitored in the serum. We experienced two ES patients with elevated serum CA125 level. One patient was a 29-year-old woman with ES in her pubic area and the other a 26-year-old man with a tumor in his right calf. Laboratory examination revealed that the CA125 values of both patients were high and changed in accordance with the progress of the tumor growth. An immunohistochemical study demonstrated that the tumor cells in both cases expressed CA125. These results suggest that CA125 can be used as a useful tumor marker for diagnosing and monitoring tumor progress.

Adult↗
PubMed2003

Radiologically and histologically mixed liposarcoma: a report of two biphasic cases.

We report two cases of liposarcomas showing biphasic patterns, radiologically and histologically. The first case was a 52-year-old man with a 17 x 12 cm intramuscular tumor in the right thigh. MR imaging revealed a mass composed of two components: a fat component and another soft tissue component. Histological diagnosis revealed mixed-type liposarcoma consisting of well-differentiated and myxoid liposarcoma. The second case was a 62-year-old man with a 22 x 15 cm intramuscular tumor in the left calf. MR imaging showed a mass composed of fat and non-fat components. The histological diagnosis was well-differentiated and pleomorphic liposarcoma.

Diagnosis, Differential↗
PubMed2003

Leiomyosarcoma of the sacral bone in a patient with a past history of resection of uterine leiomyoma.

We report here a case of leiomyosarcoma in the sacrum with a differential diagnosis of metastasizing leimyoma of uterus, since the patient had a past history of resection of uterine leimyoma 19 years ago. The sacral tumor was an osteolytic lesion, 8x6 cm in size on radiological examination. Microscopically, tumor cells consisted of spindle shaped cells with moderate cellular atypia. The tumor cells invaded into the surrounding muscle tissue. Immunohistochemistry revealed that the tumor cells were positive for alpha-SMA and vimentin, and they were enclosed by type IV collagen, suggesting the presence of the basement membrane. The labeling index of Ki-67 in the tumor cells was 25%. Re-examination of leiomyomas of uterus resected 19 years ago showed that they were typical leiomyomas, showing well-circumscribed tumors, composed of well-differentiated smooth muscle cells without nuclear atypia. The presence of radiological and pathological findings of malignancy of the sacral tumor excluded the possibility of metastasizing leiomyoma, suggesting that the sacral tumor was another primary tumor.

Aged↗
PubMed2003

Selective loss of Purkinje cells in transverse and sigmoid dural arteriovenous fistulas. Report of two cases.

The histological changes that occur in brain tissue have rarely been documented in patients with dural arteriovenous fistulas (AVFs). In this study the authors report on two patients with dural AVFs in the transverse-sigmoid sinus who presented with subarachnoid hemorrhage or progressive dementia. Histological studies of the cerebellar cortices showed a selective loss of Purkinje cells, indicating an ischemic insult caused by venous hypertension. Admission N-isopropyl-p-123I-iodoamphetamine single-photon emission computerized tomography scans demonstrated a decrease in cerebral blood flow, including flow through the cerebellum. Venous hypertension caused by transverse-sigmoid sinus dural AVFs provokes an ischemic condition severe enough to cause selective neuronal damage in the cerebellum.

Aged↗
PubMed2003

Inflammatory demyelinating disease mimicking malignant glioma.

UNLABELLED: The differential diagnosis between inflammatory demyelinating disease and malignant glioma is difficult based only on neuroimaging methods. METHODS: Four patients with inflammatory demyelinating disease who presented with clinical and neuroimaging findings strongly suggestive of malignant glioma were examined. RESULTS: MRI showed a mass lesion with prolonged T1 and T2 values and gadolinium enhancement in all cases. Proton MR spectroscopy and (201)Tl SPECT showed findings supportive of the diagnosis of malignant glioma in all cases. However, surgical biopsy revealed inflammatory demyelinating disease. After the diagnosis, 2 patients were treated by steroid administration and 2 were just observed. The gadolinium enhancement of all lesions decreased and finally disappeared. CONCLUSION: Such cases illustrate the importance of considering a demyelinating lesion in the differential diagnosis of a mass lesion. The difficulties encountered in establishing the correct diagnosis of inflammatory disease are related to the variations in the radiologic appearance, which require exclusion of gliomas or other brain tumors by surgical biopsy before the therapeutic strategy can be selected.

Adult↗
PubMed2002

Relevance of chemical structure and cytotoxicity to the induction of chromosome aberrations based on the testing results of 98 high production volume industrial chemicals.

Over a 6-year period (1991-1996), the chromosomal aberration testing of high production volume (HPV) industrial chemicals had been conducted using Chinese hamster lung (CHL/IU) cells according to OECD HPV testing program and the national program in Japan. A total of 98 chemicals were tested for the induction of chromosome aberration (CA), consisting of structural CA and polyploidy. Of the 98 chemicals, structural CA and/or polyploidy were induced by 39 chemicals (40%). Anilines and phenols tended to induce only structural CA. p-tert-Butylphenol had a peculiar feature in inducing not only structural CA but also polyploidy at considerably high frequency (93.2%) after continuous treatment for 48 h, posing an aneugenic potential. Not all, but six of 11 carboxylic acids or esters also showed the simultaneous induction of structural CA and polyploidy. The majority of organic phosphates, alcohols or ethers, alkyl benzenes and non-cyclic alkanes had no CA induction activity. For chemicals which were negative in the bacterial reverse mutation assay (Ames test), the proportion of the chemicals that induced CA at a severely cytotoxic dose (doses manifesting more than 50% cytotoxicity) was similar to that of the CA-negative chemicals manifesting severe cytotoxicity, suggesting that severely cytotoxic chemicals do not always induce CA.

Alcohols↗
PubMed2002

Hypoglossal neurinoma presenting with intratumoral hemorrhage.

Focal or microscopic hemorrhage in a neurinoma is common, but tumor origin from the hypoglossal nerve and extensive symptomatic intratumoral hemorrhage are both rare. A 59-year-old male presented with severe neck pain, nausea and vomiting of 1-day duration, accompanied by right hypoglossal nerve palsy. Neuroimaging disclosed a tumor located in the right cerebellomedullary fissure and containing a hematoma. The right hypoglossal canal was slightly dilated. The intracranial tumor was resected via a suboccipital approach. Histological examination demonstrated spindle-shaped tumor cells with nuclear palisading and also relative hypervascularity with hyaline degeneration of the vessels. Extensive hemorrhage was present, as was necrosis. Thickening and hyalinization of arterial walls, a common occurrence in neurinomas, may have contributed to symptomatic intratumoral hemorrhage.

Cranial Nerve Neoplasms↗
PubMed2002

Intramedullary plasma cell granuloma in the cervicothoracic spine. Case report.

Intraspinal plasma cell granuloma, which is a nonneoplastic entity, is extremely rare. To date, only four cases have been documented in the spinal meninges. The authors report the first case of a C7-T1 intramedullary plasma cell granuloma. After excision of the lesion, the patient's gait and bladder dysfunction improved. This plasma cell granuloma initially showed no delineated mass on T1-weighted magnetic resonance (MR) images, low signal intensity on T2-weighted images, and was well enhanced after administration of gadolinium diethylenetriamine pentaacetic acid. The latter MR imaging modality should help to detect this tumorous lesion. Histologically, the granuloma needs to be distinguished from lymphoplasmacyte-rich meningioma and plasmacytoma.

Cervical Vertebrae↗
PubMedDate not supplied

Cholangiocarcinoma arising from preexisting biliary hamartoma of liver--report of a case.

We describe the case of a 72-year-old asymptomatic man with a cholangiocarcinoma arising from a biliary hamartoma, also referred to as "von Meyenburg's complex". The patient was clinically diagnosed as having a cystadenocarcinoma, but the tumor had already been present as a uniformly low-density area on computed tomography taken four years previously, as revealed by retrospective examination of the computed tomography films that had been taken annually after surgery for pulmonary emphysema. The low-density area had continued to enlarge year after year, and a high-density area was observed to have emerged inside the low-density area on computed tomography. Histopathological examination demonstrated that the high-density area corresponded to the cholangiocarcinoma and the low-density area to a biliary hamartoma. This is the first case in which it was possible to confirm the presence of cholangiocarcinoma inside a biliary hamartoma that had continued to increase in size.

Aged↗