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Kaori Kameyama

Publications and source records attributed to Kaori Kameyama.

At least 19 recordsLinked to original sources
PubMed2006

Imaging findings of solitary fibrous tumor of the prostate: a case report.

The imaging findings of a solitary fibrous tumor of the prostate are presented. A 35-year-old male presented with urinary retention and was found on transrectal ultrasonography to have a hypoechoic tumor of the prostate, measuring 5.5 cm in size. Magnetic resonance imaging on, the tumor showed low signal intensity on T1-weighted images and heterogeneous mixed signal intensity on T2-weighted images. Gadolinium-enhanced dynamic study showed gradual enhancement from the periphery to the center, and the enhancement is sustained. On immunohistochemistry, the spindle cells of the tumor showed positive staining for CD34 and bcl-2. Although the tumor was labeled as a low-grade malignancy on account of a low mitotic index (MIB-1 index) of about 5%, the patient developed local recurrence of the tumor with bladder wall invasion 12 months later.

Adult↗
PubMed2006

Suitability of calcium phosphate cement for injection laryngoplasty in rabbits.

Calcium phosphate cement (CPC) consists of powder and liquid, which become an injectable paste after mixing, self-hardening and recrystallizing to calcium hydroxylapatite (CaHA) after injection into a living body. In this study, we investigated the suitability of CPC as an injectable material for injection laryngoplasty using rabbits. All rabbits underwent left recurrent laryngeal nerve section and injection laryngoplasty with CPC. At 7 days, scanning electron microscopic findings revealed that complete recrystallization from CPC to CaHA was achieved in the larynx. At 1, 3, and 6 months, injected CPC stayed in the paraglottic space and did not migrate, and the average remaining CPC volume percentage was 91.7%. Focal foreign body reaction to injected CPC was almost the same as that of autologous fat for all time periods observed. These results indicated that CPC appears to be biocompatible, nonabsorbable, nonmigratory, and suitable for injection laryngoplasty.

Animals↗
PubMed2006

Interim results of sentinel node biopsy during laparoscopic gastrectomy: possible role in function-preserving surgery for early cancer.

INTRODUCTION: Intraoperative detection of sentinel nodes (SNs) has been used clinically to predict regional lymph node (LN) metastasis in patients with breast cancer and malignant melanoma. Intraoperative lymphatic mapping and SN biopsy can potentially be combined with minimally invasive surgery. However, few reports have demonstrated the validity of SN biopsy during laparoscopic gastrectomy. The aim of this study was to investigate the feasibility and accuracy of laparoscopic lymphatic mapping in predicting LN status in patients with gastric cancer. METHODS: A total of 35 patients with gastric cancer diagnosed preoperatively as T1, N0 were enrolled. Endoscopic injection of technetium-99m-radiolabeled tin colloid was completed 16 hours before surgery, and radioactive SNs were identified with a gamma probe intraoperatively. Isosulfan blue dye was injected endoscopically during the operation. Laparoscopy-assisted gastrectomy with LN dissection was performed. All resected LNs were evaluated by routine pathology examination. RESULTS: SNs were detected in 33 (94.3%) of 35 patients. The mean number of SNs was 3.9, and the diagnostic accuracy according to SN status was 97.0% (32/33), as one patient with a false-negative result was observed. The patient with the false-negative specimen was finally diagnosed as having advanced gastric cancer with invasion into the proper muscular layer and severe lymphatic vessel invasion, causing destruction of normal lymphatic flow by the tumor. CONCLUSIONS: Radio-guided SN mapping during laparoscopic gastrectomy is an accurate diagnostic tool for detecting lymph node metastasis in patients with early-stage gastric cancer. Validation of this method requires further studies on technical issues, including indications, tracers, methods of lymph node retrieval, and diagnostic modalities of metastasis.

Adult↗
PubMed2006

Gallbladder carcinoma with osteoclast-like giant cells.

Extraskeletal tumors containing multinucleated, osteoclast-like giant cells (OGCs) are uncommon. These neoplasms are most frequently reported in the breast and pancreas. Recently, some authors have suggested that carcinomas containing OGCs may represent a distinct clinicopathological entity with a more favorable prognosis. Occurrence in the gallbladder is extremely rare, with only one previous case. We report here on an additional case of gallbladder carcinoma with an infiltrate of OGCs. A 72-year-old woman presented with postprandial abdominal pain and was found to have a mass in the body of the gallbladder with direct liver invasion. Histological examination showed an adenosquamous carcinoma with an infiltrate of benign OGCs. Immunohistochemical analysis demonstrated that the giant cells were of histiocytic origin. The patient survived for 6 years without evidence of recurrence. This case adds to a small body of literature on gallbladder carcinoma with OGCs. Further studies are required to clearly define the prognostic significance of these giant cells in gallbladder cancer and the differences between adenosquamous carcinoma with OGCs and other gallbladder carcinomas (such as adenocarcinoma and squamous cell carcinoma) with those cells.

Aged↗
PubMed2006

Inflammatory pseudotumor of the liver masquerading as hepatocellular carcinoma after a hepatitis B virus infection: Report of a case.

We report a rare case of hepatic inflammatory pseudotumor (IPT) after a hepatitis B virus (HBV) infection. Early contrast enhancement on computed tomography (CT) with a washout phenomenon at the delayed phase, and depleted Kupffer cell function on superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance imaging (MRI) suggested hepatocellular carcinoma (HCC). However, the lack of a tumor capsule, absence of liver cirrhosis, and normal serum levels of alpha-fetoprotein and PIVKA-II (protein induced by vitamin K absence; descarboxyprothrombin) contradicted this diagnosis. We excised the tumor to exclude malignancy, and the histopathological diagnosis was IPT. Recent evidence suggests that this entity has changed from an extremely rare pathology to an established disease. Thus, IPT should be considered in the differential diagnosis of a liver mass with an infectious-inflammatory antecedent. Although surgery is not mandatory, surgical removal is recommended if there is a possibility of malignancy. Further investigations are warranted to elucidate the mechanisms of IPT developing after an HBV infection.

Angiography↗
PubMed2006

Tamoxifen for recurrent desmoid tumor of the chest wall.

We report a case of a young woman with recurrent desmoid tumor. Computed tomography (CT) scans of the chest showed a large mass in the left chest wall. The tumor was unresectable because of the involvement of adjacent structures. Tamoxifen therapy led to marked tumor regression within 3 months. She had preserved her fertility, and thereafter she conceived a baby. In young women with recurrent desmoid tumor, tamoxifen should be considered as the first choice of treatment.

Adult↗
PubMed2006

Large renal artery aneurysm in Takayasu arteritis.

Takayasu arteritis (TA), a primary arteritis of unknown cause, commonly affects the aorta and its main branches. Most patients with TA have stenotic or occlusive changes; aneurysmal degeneration is relatively rare, and renal artery aneurysms are extremely rare. We observed a fusiform, 7-cm renal artery aneurysm in a 57-year-old man with TA who had been followed up for 17 years. The patient underwent nephrectomy and resection of the aneurysm. Histologic examinations of resected specimens of the lesion showed characteristics typical of TA.

Aneurysm↗
PubMed2006

Operative indications for relatively small (2-5 cm) gastrointestinal stromal tumor of the stomach based on analysis of 60 operated cases.

BACKGROUND: Removal of the primary lesion with a clear operative margin is the standard treatment for gastrointestinal stromal tumor (GIST) of the stomach. However, there are few reports on the operative indications for relatively small GIST. METHODS: Clinicopathologic features and survival data of all 60 patients with GIST of the stomach treated at Keio University Hospital from 1993 to 2004 were analyzed. Laparoscopic wedge resection was used as the primary procedure for tumors between 2 to 5 cm. Tumors larger than 5 cm were resected by laparotomy or laparoscopy-assisted operation. RESULTS: Thirty-five lesions (58.3%) were resected by laparoscopic wedge resection, 3 by laparoscopic operation with a small skin incision and 22 by conventional open procedures. The mean size of the tumors was 42.5 mm, with a range of 18 to 150 mm and a median value of 35.5 mm. All operative margins were clear, but 1 patient had liver metastases at the time of resection of the primary lesion. The median follow-up period was 53 months and the 5-year disease-free survival rate (DFS) was 96.1%. No local recurrence or distant metastasis was encountered in patients with tumors smaller than 4 cm. A statistically significant correlation was observed between tumor size and mitotic count in this cohort (P = .010). Tumors from the intermediate- (n = 14) and high-risk (n = 10) groups as classified by the Risk Assessment Classification showed significantly worse DFS than the low-risk and very low risk group (n = 35) (89.9% vs 100% in 5-year DFS, P = .045). Even among tumors smaller than 3 cm, 2 of 14 cases (14.3%) were classified into the intermediate-risk group. CONCLUSIONS: Although a prospective randomized trial remains to be performed, this study provides additional evidence suggesting that the early removal of GIST, at 5 cm or less in size, provides better DFS than later removal of the tumor at a larger size.

Adult↗
PubMed2006

Ocular complications in a child with acute graft-versus-host disease following cord blood stem cell transplantation: therapeutic challenges.

We present the first child case of pseudomembranous conjunctivitis accompanied by an extensive corneal ulcer with acute graft-versus-host disease (GVHD) after cord blood stem cell transplantation (CBSCT). The histopathology of the pseudomembrane and the ocular changes following its excision were investigated specifically. One week after the excision of pseudomembrane, the extensive corneal epithelial defects had totally disappeared. Pseudomembrane excision may be an effective method of treatment in corneal epithelial defects observed after GVHD.

Acute Disease↗
PubMed2005

RET gene rearrangements (RET/PTC1 and RET/PTC3) in papillary thyroid carcinomas from an iodine-rich country (Japan).

BACKGROUND: The frequency of RET rearrangements (RET/PTC) in papillary thyroid carcinomas varies significantly according to geographic area, with the greatest incidence reported in the Belarus region, which is iodine-deficient and was contaminated severely after the Chernobyl reactor accident, and with the lowest incidence in iodine-rich, nonirradiated Japan. The authors investigated the prevalence of RET/PTC in a large number of thyroid tumors from Japanese patients. METHODS: Fresh and paraffin embedded tumor tissues from 215 Japanese patients were examined for RET rearrangements (RET/PTC1 and RET/PTC3) by means of reverse transcriptase-polymerase chain reaction analysis, with primers flanking the chimeric region, followed by direct-sequence analysis. RESULTS: RET/PTC was found only in papillary carcinomas and was not observed in other histologic types of thyroid tumors. The overall frequency of RET/PTC in papillary carcinomas was 28.4%, with a greater frequency in younger patients, including 41.9% of younger patients age < 20 years, 27.6% of patients age 20-40 years, and 24.8% of patients age > 40 years. Among the patients in these 3 age groups, the prevalence rate of RET/PTC1 was similar, but RET/PTC3 was observed most frequently among patients age < 20 years. When the tumors were grouped further according to histologic subtypes, the prevalence of RET/PTC3 was greater in solid/solid-follicular papillary carcinomas than in classic papillary carcinomas. CONCLUSIONS: The results indicated that RET/PTC may be useful as a specific molecular marker for papillary thyroid carcinomas. Furthermore, its incidence in such tumors was not low in Japanese patients, and it seemed to be associated with patient age. Therefore, the current results raise questions regarding the belief that the frequency of RET/PTC differs geographically and is especially low in Japan.

Adult↗
PubMed2005

Primary undifferentiated spindle-cell carcinoma of the gallbladder presenting as a liver tumor.

Undifferentiated spindle-cell carcinoma (SpCC) of the gallbladder is extremely rare. There is very little information available regarding the characteristics and treatment of this disease. We herein report the unique case of a 76-year-old female patient with a primary SpCC of the gallbladder that presented as a liver tumor. Preoperative radiologic examinations showed a 5-cm liver tumor around the gallbladder bed, and irregular thickening of the gallbladder wall. The patient underwent en-bloc resection of the gallbladder and segments 4b and 5 of the liver (including the liver tumor). Microscopic findings revealed that both lesions consisted mainly of a sarcomatous spindle-shaped component. Small foci of well-differentiated adenocarcinoma cells were identified in the gallbladder mucosa. There was a gradual transition between the two different components, thereby implying that these two cell types had a common origin. Immunohistochemical studies showed that the spindle-shaped cells were epithelial in nature. The patient's postoperative course was uneventful. However, she died of recurrent liver disease 6 months after the surgery. In conclusion, we surmised that the sarcomatous spindle cells originated from a carcinomatous component in the gallbladder mucosa through dedifferentiation. Further studies are needed to better understand the characteristics of this deadly tumor, and to establish an effective therapy for it.

Adenocarcinoma↗
PubMed2005

Gastric cancer mimicking a submucosal tumor diagnosed by laparoscopic excision biopsy.

We report a case of advanced gastric cancer exhibiting the features of a submucosal tumor (SMT) of the gastric body. The patient was a 50-year-old male in whom a gastric SMT was detected during a mass screening examination. Upper gastrointestinal endoscopy revealed a protuberant tumor, 2 cm in diameter, covered with normal-appearing mucosa. Examination of an endoscopic biopsy specimen of the tumor revealed chronic gastritis with regenerative and erosive changes. An endoscopic ultrasound examination demonstrated a hypoechoic mass in the third layer of the gastric wall. The clinical diagnosis was gastric SMT, and the patient's course was monitored. Twenty-six months after the initial visit to our hospital, an endosonograph-guided biopsy revealed Group III (borderline lesion). Three months after the biopsy, the size of the SMT had increased slightly. Laparoscopic wedge resection of the tumor was performed to make a pathologic diagnosis and we were able to make a diagnosis of gastric lymphoepithelioma-like carcinoma intraoperatively. Gastrectomy with lymph node dissection was followed as curative surgery. Laparoscopic total excision biopsy is a useful technique in patients with a gastric SMT whose diagnosis has not been confirmed pathologically.

Biopsy↗
PubMed2005

Donor fibroblast chimerism in the pathogenic fibrotic lesion of human chronic graft-versus-host disease.

PURPOSE: Tissue atrophy and excessive fibrosis are prominent histologic features of chronic graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation, but the underlying mechanism remains unknown. The current study was undertaken to investigate whether the increase in fibroblasts at the site of pathogenic fibrosis originated from transplanted donor cells in patients with chronic GVHD. METHODS: Lacrimal gland biopsy specimens were obtained from nine patients with chronic GVHD. The male-specific sequences detected by fluorescein in situ hybridization (FISH) and in situ hybridization (ISH) were used as markers for the donor cells in seven female patients who had received a transplant from male donors. Primary fibroblast cultures were generated from lacrimal gland biopsy specimens and examined for mismatched genetic markers between recipients and donors. RESULTS: In lacrimal gland specimens obtained from seven female patients who received a sex-mismatched transplant, 13.4% to 26.7% of CD34+ fibroblasts that accumulated in the fibrotic lesion were donor derived, as determined by FISH for the Y-chromosome. The male-specific mRNA was also detected in the lacrimal gland fibroblasts by ISH. Primary lacrimal gland fibroblast cultures were generated from four patients with chronic GVHD and further examined for mismatched genetic markers between recipients and donors. As a result, the presence of donor origin of the fibroblasts was demonstrated by detecting the Y-chromosome sequence and donor-specific microsatellite genetic markers. CONCLUSIONS: These findings together indicate the chimeric status of accumulated CD34+ fibroblasts in the lacrimal gland of patients with chronic GVHD. Fibroblasts originating from circulating donor-derived precursors may participate in the excessive fibrosis in these patients.

Adult↗
PubMed2005

A cavernous haemangioma of the thyroid gland.

Haemangioma of the thyroid gland is extremely rare. We report a case of a cavernous haemangioma of the neck that was located both inside and outside the thyroid gland of a 21-year-old man. Ultrasonography of the neck revealed numerous calcified nodules. Computed tomography (CT) showed a large calcified soft tissue mass in the right lobe of the thyroid. Based on the imaging findings a papillary thyroid carcinoma was suspected, but examination of the surgical specimen revealed a huge cavernous haemangioma containing numerous phleboliths.

Adult↗
PubMed2005

Proposal for the histological classification of parathyroid carcinoma.

Although the criteria of Schantz and Castleman are widely used in the diagnosis of parathyroid carcinoma, many tumors diagnosed as carcinoma subsequently do not recur. In addition, although Bondeson's criteria are used to grade parathyroid carcinoma, instances of patient mortality have been documented even in cases where the histological features did not conform to the criteria for high grade. Considering our experience, we believe that the subclassification of parathyroid carcinomas defining tumors limited local infiltration as low-grade and those with widespread infiltration as high-grade may be useful.

Carcinoma↗
PubMed2005

[Immunohistochemical study is helpful for the diagnosis of cerebellar clear cell ependymoma with atypical radiological findings--case report].

A 67-year-old male presented with a clear cell ependymoma with symptoms of ataxic gait and dizziness. Magnetic resonance imaging showed a ring enhanced and circumscribed mass lesion with some cysts in the left cerebellar hemisphere, and the vertebral artery angiogram showed the vascurality of the tumor fed by both the left posterior inferior cerebellar artery and the left superior cerebellar artery mainly. They demonstrated suspicious finding of metastatic tumor, glioblastoma, or cystic meningioma. Surgery via the left suboccipital approach revealed a whitish and solid tumor, which was demarcated from the cerebellar parenchyma and had no continuity with the 4th ventricle. Total resection of the tumor was successfully performed. The hematoxilyn-eosin staining of the surgical specimen was similar to hemangioblastoma or oligodendroglioma, however, immunohistochemical findings for glial fibrillary acidic protein, vimentin, epithelial membrane antigen, and factor VIII were compatible with clear cell ependymoma. The patient's postoperative course was uneventful, and his symptoms improved. Clear cell ependymoma is known as a variant of ependymoma, which is usually located at the foramen of Monro. We think that the immunohistochemical study is highly helpful for the diagnosis of the cerebellar tumor with atypical presentation such as our case.

Aged↗
PubMed2004

Malignant transformation of sialadenoma papilliferum of the palate: a case report.

We report a case of a 79-year-old woman with an unusual salivary gland tumor that developed at the junction between the soft and hard palates. The tumor consisted of sialadenoma papilliferum (SP) with areas of an epithelial-myoepithelial carcinoma (EMC) component and a high-grade carcinoma component. There were also transitional regions among the SP, the EMC and the high-grade carcinoma components. The high-grade carcinoma component, which was similar to invasive micropapillary carcinoma of the breast, infiltrated into the right parapharyngeal space and metastasized to the lungs and cervical vertebrae. The high-grade carcinoma cells were positively immunostained for p53 protein. SP has been considered to be a benign tumor with exceptionally good prognosis, and, to the best of our knowledge, there has never been a confirmed case of malignant SP. This is the first report of SP with a definite malignant component.

Aged↗