Pancreatic serous microcystic adenoma with extensive oncocytic change

Herein is reported a case of pancreatic serous microcystic adenoma with extensive oncocytic change in a 73-year-old woman. Histologically the tumor consisted of numerous small cysts, separated by thin or broad fibrous septa. These cysts were lined with uniform cells having abundant eosinophilic granular cytoplasm, which was negatively or weakly stained with PAS. Immunohistochemically, the cyst-lining cells were positive for cytokeratin (CK) 7, CK19, MUC1, MUC6, alpha-inhibin, and neuron-specific enolase (NSE), and negative for CK8, CK20, MUC2, and MUC5AC; these immunoprofiles coincide with those of serous microcystic adenoma. Immunostaining with anti-mitochondrial antibody showed dense granular positivity in the cytoplasm, which suggested an oncocytic phenotype. Thus, this case is considered a variant of serous microcystic adenoma characterized by extensive oncocytic change. To the authors' knowledge no similar case has been reported in the literature. It may pose problems in the differential diagnosis of the cystic pancreatic tumors with oncocytic change, but can be diagnosed on histology and immunohistochemistry.

Successful treatment of KIT D816V-positive, imatinib-resistant systemic mastocytosis with interferon-alpha

We describe a case of systemic mastocytosis associated with myelodysplastic syndrome. The bone marrow showed multifocal clusters of mast cells and myeloid dysplasia. Sequencing of the KIT DNA revealed a point mutation at codon 816 including a substitution of valine for aspartic acid (D816V). The patient's tumor did not respond to imatinib; however, interferon-alpha reduced the bone marrow mast cells and serum total tryptase. The patient remains alive at one year after the diagnosis without disease progression.

CD8+, CD56+ (natural killer-like) T-cell lymphoma involving the small intestine with no evidence of enteropathy: clinicopathology and molecular study of five Japanese patients

The present study reports five CD8+, CD56+ (natural killer (NK)-like) T-cell lymphomas involving the small intestine without evidence of enteropathy, from Japan. Three were intestinal T-cell lymphoma. The site of origin of the other two was not definitive. Four of five patients underwent emergency operation because of intestinal perforation. The small intestines of these patients had multiple ulcerative lesions with or without demarcated tumors. Histologically, the lymphoma cells were monomorphic or slightly pleomorphic and displayed epitheliotropism of varying degrees. Lymphoma cells of all patients shared the common phenotype: CD3+, CD4-, CD5-, CD8+, CD56+, CD57-, T-cell intracellular antigen-1+, granzyme B+. In contrast to nasal/nasal type NK-cell lymphomas, they had clonal rearrangement of T-cell receptor(TCR) genes and were negative for EBV-encoded RNA. Immunohistochemistry and genetics suggested that three cases were of alpha beta T-cell origin and two cases were of gamma delta T-cell origin. There was no evidence of enteropathy in any patient. The cases followed a clinically aggressive course with a frequent involvement of lung. According to the classification based on the recent genetic studies of European enteropathy-type intestinal T-cell lymphoma (ETL), the present cases could be classified as type 2 ETL.

Relationship between coronary remodeling and plaque characterization in patients without clinical evidence of coronary artery disease

AIMS

The objectives of this study were: (1) to evaluate the relationship between coronary arterial remodeling assessed by intravascular ultrasound (IVUS) and plaque morphology assessed by histological examination in patients without clinical evidence of coronary artery disease and (2) to compare plaque morphology between histological examination and optical coherence tomography (OCT).

METHODS

Coronary segments (n=98) were harvested from the heart of 34 patients who died without clinical evidence of coronary artery disease. The segments with remodeling were assessed by IVUS and compared with corresponding OCT and histological images.

RESULTS

The fibrofatty plaque area was larger in lesions with expansive remodeling (ER) than in lesions with intermediate/constrictive remodeling (IR/CR) (p<0.01). Incidence of lipid containing plaque with the thickness of the fibrous cap smaller than 200 microm tended to be higher in ER than in IR/CR (34% versus 13%, p=0.10). OCT assessment of lipid containing plaque with thinner fibrous cap was achieved with 92% sensitivity and 75% specificity.

CONCLUSIONS

The fibrofatty plaque area was larger in lesions with ER than IR/CR even in patients without clinical evidence of coronary artery disease. The current capabilities of OCT are well suited for evaluation of lipid containing plaques with thinner fibrous cap.

[Clinical analysis of eight patients with primary follicular lymphoma in the duodenum]

We performed a clinical analysis on 8 patients with primary follicular lymphoma in the duodenum taken from among 26 cases of primary gastrointestinal malignant lymphoma treated in our division. The median age was 60 years (range 48 to 82 yr). The ratio of males to females was 4:4. The chief complaints were no symptoms in 4 cases, heartburn in 2 cases, lower abdominal pain in 1 case, and back pain in 1 case. All patients were in clinical stage I EA. Gastroendoscopic findings showed multiple whitish granules around the ampulla of Vater in all patients. Involvement of the site in 6 cases was only located at the second portion; lesions in the other 2 cases were located at the second portion, and at the third portion or fourth portion, respectively. A histological study showed follicular lymphoma grade 1, and an immunohistological study demonstrated that the lymphoma cells were positive for CD79a, CD10, CD20, and bcl-2. Five patients were positive for the FISH analysis fusion signal of IgH/bcl-2 genes. Rituximab with CHOP therapy was performed for 7 patients. Seven patients are currently alive, and one died of uterine cancer. At the medium-term 39 month-follow-up, 7 patients were in complete remission, and 1 patient was in partial remission. Rituximab with CHOP (CVP) therapy is a possible treatment for primary follicular lymphoma in the duodenum. Further consideration of appropriate therapy for this disease might be necessary.

Assessment of the Histological Characteristics of Coronary Arterial Plaque With Severe Calcification

BACKGROUND

Several studies have shown that rotational atherectomy (RA) is associated with higher rates of the slow-flow phenomenon and that ablated particles may be the possible cause. Intravascular ultrasound (IVUS) has an intrinsic limitation in assessing plaque morphology behind the calcification because of acoustic shadowing. Therefore, the purpose of this study was to investigate plaque characteristics behind severe calcification by histological examination.

METHODS AND RESULTS

One hundred eight coronary arterial segments from 40 human cadavers (24 males, 16 females, mean age 74+/-7 years) were examined. Serial images of IVUS were obtained and 18 severe calcified lesions were collected. Experienced observers quantitatively analyzed the lesions by computerized planimetry for fibrous, fibrofatty, calcification, and necrotic tissue area. Histologically, 15 of 18 severely calcified lesions (83%) had an extensive necrotic tissue containing large numbers of cholesterol crystals and microcalcifications; 16 of same 18 severely calcified lesions (89%) had fibrofatty tissue as well as calcification. The necrotic tissue occupied 14+/-13% and fibrofatty tissue occupied 13+/-11% of severely calcified lesions.

CONCLUSION

Necrotic core and fibrofatty tissue components "hidden" behind calcification might cause emboli-induced thrombus formation and distal flow disturbance during RA.

Follicular lymphoma frequently originates in the salivary gland

The aim of the present study was to examine the clinicopathological presentations of follicular lymphomas (FL) of the salivary glands, as compared to mucosa-associated lymphoid tissue (MALT) lymphomas. A total of 27 primary salivary gland lymphomas were examined: 6 FL (five, grade 1; one, grade 2); 19 MALT lymphomas; and two diffuse large B-cell lymphomas. The FL patients ranged in age from 24 to 73 years, with a mean of 49 years, which was younger than that of MALT patients (mean: 64 years; P < 0.05). Four of the six FL arose from the submandibular gland, which was the origin of only five out of a total of 19 MALT lymphomas. One FL patient was in clinical stage (CS) IE, two in CS IIE, and two in CS III and IV. As regards the MALT lymphoma patients, 13 (68%) were in CS IE and five (26%) in CS IIE. None of the FL patients had clinical diagnosis of autoimmune disease but eight MALT lymphoma patients had autoimmune disease. The present study found a relatively high incidence of FL in the salivary glands. The observed differences in age of onset, background of autoimmune disease, and lesion site suggests that the pathogenesis of FL may differ from that of MALT lymphoma.

Measurement of the thickness of the fibrous cap by optical coherence tomography

BACKGROUND

Identification of the fibrous cap is important because its thickness is a major determinant of plaque vulnerability in lipid-rich plaque. Thus, a high-resolution imaging technique may be a promising method for the identification of the fibrous cap within lipid-rich plaque. The purpose of this study was to investigate the feasibility of using optical coherence tomography (OCT) to measure the thickness of the fibrous cap within lipid-rich plaque.

METHODS AND RESULTS

We examined 35 lipid-rich plaques from 102 coronary arterial segments of 38 human cadavers (22 men and 16 women; mean ages, 74 +/- 7 years). Optical coherence tomography and corresponding histological images were digitized for measurement of the thickness of fibrous cap, and the results between OCT and histological examination were compared. There was good correlation of the thickness of the fibrous cap between OCT and histological examination (y = 0.97x + 28.49; r = 0.90; P < .001). A Bland-Altman test showed good agreement of the thickness of the fibrous cap between OCT and histological examination (mean difference, -24 +/- 44 microm).

CONCLUSIONS

Optical coherence tomography provides an accurate representation of the thickness of the fibrous cap and may prove useful in assessing plaque vulnerability in lipid-rich plaque.

Assessment of coronary arterial thrombus by optical coherence tomography

We analyzed optical coherence tomographic (OCT) characteristics of different types of coronary thrombi that had been confirmed at postmortem histologic examination. We examined 108 coronary arterial segments of 40 consecutive human cadavers. OCT images of red and white thrombi were obtained and the intensity property of these thrombi was analyzed. Red and white thrombi were found in 16 (17%) and 19 (18%) of the 108 arterial segments, respectively. Red thrombi were identified as high-backscattering protrusions inside the lumen of the artery, with signal-free shadowing in the OCT image. White thrombi were identified as low-backscattering projections in the OCT image. There were no significant differences in peak intensity of OCT signal between red and white thrombi (130+/-18 vs 145+/-34, p=0.12). However, the 1/2 attenuation width of the signal intensity curve, which was defined as the distance from peak intensity to its 1/2 intensity, was significantly different between red and white thrombi (324+/-50 vs 183+/- 42 microm, p<0.0001). A cut-off value of 250 microm in the 1/2 width of signal intensity attenuation can differentiate white from red thrombi with a sensitivity of 90% and specificity of 88%. We present the first detailed description of the characteristics of different types of coronary thrombi in OCT images. Optical coherence tomography may allow us not only to estimate plaque morphology but also to distinguish red from white thrombi.

Assessment of coronary arterial plaque by optical coherence tomography

The purpose of this study was to analyze the ability of optical coherence tomography (OCT) to identify coronary arterial plaque diagnosed by histologic examination. We examined 166 sections from 108 coronary arterial segments of 40 consecutive human cadavers (24 men and 16 women; mean age 74 +/- 7 years). The plaque type was classified as fibrous (n = 43), fibrocalcific (n = 82), or lipid-rich (n = 41). The accuracy of OCT and intravascular ultrasound (IVUS) in characterizing the plaque type was studied, with the histologic consensus diagnosis serving as the gold standard. OCT, as well as IVUS, had high sensitivity and specificity for characterizing the different types of atherosclerotic plaque. OCT had a higher sensitivity for characterizing lipid-rich plaques than IVUS (85% vs 59%, p = 0.03). In conclusion, the high resolution of OCT permitted evaluation of lipid-rich plaques more accurately than IVUS.

In vitro detection of cross-resistant and non-cross-resistant agents with fluorouracil for patients with colorectal cancer

BACKGROUND

Fluorouracil-based chemotherapy, such as that with 5-fluorouracil (5-FU)/leucovorin, is standard as first-line chemotherapy for advanced colorectal cancer (CRC) in Japan. However, the best agent for second-line chemotherapy after fluorouracil failure is yet to be determined. This study was undertaken to find an appropriate agent for second-line chemotherapy.

METHODS

Seventy-five tumor specimens from CRC patients with no prior chemotherapy were obtained operatively and their chemosensitivity to five anticancer agents; i.e., 5-FU, mitomycin C (MMC), cisplatin, docetaxel, and an active metabolite of irinotecan (SN-38), was analyzed in an in vitro chemosensitivity test. In this method, the degree of chemosensitivity was expressed as the percent T/C ratio, where T was the total volume of the tumor colonies in the treated group and C was that of the control group. Pearson's correlation coefficients were used to assess the relationship between two agents.

RESULTS

Fifty-eight specimens (colon, 28; rectum, 30) were successfully analyzed. Positive correlations with 5-FU chemosensitivity were verified for the chemosensitivity of MMC, cisplatin, and docetaxel. No correlation with 5-FU chemosensitivity was verified for SN-38 chemosensitivity. Although the functional mechanism of each of the agents differs from that of 5-FU, with the exception of irinotecan, they all had a spectrum closely similar to the 5-FU spectrum.

CONCLUSION

Only irinotecan exhibited a spectrum independent of that of 5-FU, thus indicating that it could be an appropriate agent for second-line chemotherapy after fluorouracil failure.

Hypoxia-inducible factor-1 drives the motility of the erythroid progenitor cell line, UT-7/Epo, via autocrine motility factor

OBJECTIVE

It is well known that hypoxic stress strongly enhances erythropoiesis, but the effect of hypoxia on erythroid progenitors has not been examined precisely. In the present study, using the erythropoietin-dependent cell line UT-7/Epo, which has characteristics of erythroid progenitors, we investigated a novel role of hypoxia in erythropoiesis.

METHODS

UT-7/Epo and four other hematopoietic and lymphoid cell lines (HL-60, THP-1, Raji, and CEM) were cultured in 20%, 5%, or 1% O2. Morphology was observed under a phase-contrast microscope. Cell motility was evaluated using the Transwell migration assay. An analysis of the protein level of hypoxia-inducible factor-1 (HIF-1) alpha and autocrine motility factor (AMF) was conducted using Western blotting and immunocytochemistry, respectively. Reverse transcription polymerase chain reaction was performed to evaluate the expression of AMF mRNA. Human bone marrow stromal cells were used in cocultures with UT-7/Epo. Apoptosis of UT-7/Epo was examined by immunocytochemistry using an antiactive form of caspase 3 antibody.

RESULTS

Among the five cell lines, UT-7/Epo exhibited active pseudopodial extension in hypoxia (1% O2), and cell motility was increased. HL-60, THP-1, Raji, and CEM did not show an increase in cell motility even in 1% O2. In addition, expression of the alpha-subunit of HIF-1 was activated by hypoxia, and expression of the mRNA and protein of AMF induced by HIF-1, increasing cell motility, was promoted. The addition of an HIF-1 inhibitor, cadmium chloride (CdCl2), or alpha-ketoglutarate (2-oxoglutarate) decreased the AMF mRNA expression, and an AMF inhibitor, erythrose 4-phosphate, decreased the cell motility. When UT-7/Epo was cocultured with human bone marrow-derived stromal cells that significantly inhibit the apoptosis of UT-7/Epo, the migration of UT-7/Epo under the stromal cells (pseudoemperipolesis) was increased in hypoxia.

CONCLUSION

Under hypoxic conditions, erythroid progenitors may exhibit active migration in the bone marrow and the opportunity for contact with stromal cells increases, inhibiting apoptosis.

Monocyte/Macrophage-specific marker CD163+ histiocytic sarcoma: case report with clinical, morphologic, immunohistochemical, and molecular genetic studies

We report a case of a very rare disorder, histiocytic sarcoma, from a review of our autopsy cases. The neoplastic cells that proliferated in organs throughout the body were large cells containing eosinophilic cytoplasm and pleomorphic nuclei with prominent nucleoli. In the bone marrow, erythrophagocytosis by neoplastic cells was observed. The neoplastic cells were positive not only for lysozymes and CD68 (KP-1, PG-M1, and Ki-M1P) but also for a monocyte/macrophage-specific marker, CD163. In contrast, the results of tests for markers of myeloid cells, lymphoid cells, and epithelial cells were all negative. In a polymerase chain reaction study of paraffin-embedded tissues, analyses for the rearrangement of immunoglobulin heavy chain and T-cell receptor-gamma genes were negative. The current World Health Organization diagnostic criteria for histiocytic sarcoma regard immunohistochemical investigation as crucial. In this regard, the highly specific positivity for CD163 in this patient indicates that immunohistochemical staining of CD163 is very useful for the diagnosis of histiocytic sarcoma.

Visualization of Neointima Formation by Optical Coherence Tomography

Optical coherence tomography (OCT) has recently been proposed as a high-resolution imaging method. Our male patient, who had been treated with a coronary stent, died due to acute leukemia. Coronary artery images using intravascular ultrasound (IVUS) and OCT were obtained postmortem. We also compared the image of neointima formation after stent implantation evaluated by histopathological examination with that evaluated by IVUS and OCT. OCT visualized well-apposed stent struts and neointima formation, which could not be visualized completely by IVUS. OCT may be useful for monitoring structural changes after stent implantation.

Assessment of Coronary Intima - Media Thickness by Optical Coherence Tomography Comparison With Intravascular Ultrasound

BACKGROUND

Optical coherence tomography (OCT) is a new imaging method. With a resolution of approximately 10-20 Em, which is approximately 10-fold higher than that of intravascular ultrasound (IVUS).

METHODS AND RESULTS

This study compared the coronary intima - media thickness (IMT) and the intimal thickness of 54 coronary arterial segments evaluated by histological examination with the results of OCT and IVUS. There was better agreement in IMT between OCT and histological examination than between IVUS and histological examination (r = 0.95, p < 0.001, mean difference = -0.01+/-0.07 mm for OCT; r = 0.88, p < 0.001, mean difference = -0.03+/-0.10 mm for IVUS). There was good agreement in the intimal thickness between OCT and histological examination (r = 0.98, p < 0.001, mean difference = 0.01+/-0.04 mm).

CONCLUSIONS

IMT could be measured more accurately by OCT than IVUS. In addition, the intimal thickness could be evaluated by OCT and correlated well with the histological examination.

Expression of protein gene product 9.5 (PGP9.5)/ubiquitin-C-terminal hydrolase 1 (UCHL-1) in human myeloma cells

The neuron cytoplasmic protein gene product 9.5 (PGP9.5)/ubiquitin-C-terminal hydrolase 1 (UCHL-1) protein is a thiol protease that recognizes and hydrolyzes a peptide bond at the C-terminal of ubiquitin, and is involved in the processing of ubiquitin precursors and ubiquinated proteins. Although this molecule is known as a specific tissue marker for the neuroendocrine system, many reports have indicated that PGP9.5 is a marker for certain tumour types, such as cancer of the lung, colon, and pancreas. The expression of PGP9.5 in myeloma cells was examined. PGP9.5 seemed to be expressed specifically in myeloma cells as compared with other haematological malignant cells. In addition, in myeloma cells subjected to growth-factor starvation, the upregulation of PGP9.5 was observed in association with that of p27(Kip1), a cyclin-dependent-kinase inhibitor, although the upregulation caused by irradiation was milder. In contrast, the hypoxic culture of myeloma cells induced down-regulation of PGP9.5. These results suggested that PGP9.5 may be a good marker for myeloma among haematological malignancies. In addition, it may indicate certain cellular features of myeloma cells, such as sensitivity to proteasome inhibitors.

[CD56-positive peripheral T-cell lymphoma primarily presenting with tonsillar swelling]

A 51-year-old woman was admitted to our hospital with tonsillar swelling. After tonsillectomy was performed, she was diagnosed as having CD56-positive T-cell lymphoma, mainly composed of small and medium-sized atypical cells. An immunohistochemical study showed that the malignant lymphocytes were positive for CD3, CD8, CD56, TIA-1 and granzyme B, while negative for CD20, CD5 and CD10. Flowcytometry demonstrated the lymphocytes were positive for CD56. Southern blot analysis revealed a rearrangement of the T-cell receptor gamma chain. The disease stage by Ann Arbor staging classification was II B. We provided MCEC therapy followed by autologous peripheral blood stem cell transplantation, and complete remission (CR) was achieved. Two months after CR, however, the patient relapsed with peritonitis due to perforation of an ileal tumor, and died of sepsis. It is rare for CD56-positive T-cell lymphoma to occur primarily in the tonsils. Because small bowel ulcers were revealed during the course of induction chemotherapy, we report a valuable case in which suspected CD56-positive enteropathy-type T-cell lymphoma (ETL) occurred primarily in the tonsils.

API2-MALT1 fusion gene in colorectal lymphoma

The API2-MALT1 fusion gene was originally identified from a t(11;18)(q21;q21) translocation, a specific chromosomal abnormality that is found in mucosa-associated lymphoid tissue (MALT) lymphoma. Gastric MALT lymphomas positive for the API2-MALT1 fusion gene do not respond to Helicobacter pylori-eradication therapy, but otherwise, the incidence and clinicopathological behavior of colorectal MALT lymphoma with this genetic abnormality are unclear. We examined the API2-MALT1 fusion by multiplex RT-PCR method in 47 cases of MALT lymphoma and 13 cases of diffuse large B-cell lymphoma and evaluated the relevance of API2-MALT1 positivity to the clinical and pathological features. The mean ages of MALT lymphoma and diffuse large B-cell lymphoma patients were 65 (range, 37-87 y) and 58 (range, 14-85 y) years, respectively. API2-MALT1 fusion genes were detected in seven cases (15%) of MALT lymphoma and one case (8%) of diffuse large B-cell lymphoma. In MALT lymphomas, the tumor size in API2-MALT1-positive cases was 62 +/- 39 mm (mean +/- SD), statistically larger than that in API2-MALT1-negative cases (25 +/- 19 mm; P <.01). The API2-MALT1-positive cases demonstrated more advanced clinical stages and a male predominance, compared with API2-MALT1-negative cases. Thus, API2-MALT1-positive tumors should be cared for as a more aggressive subgroup and be followed for a longer time.