Masamichi Suzuki

Adenoma, adenocarcinoma and mixed carcinoid-adenocarcinoma arising in a small lesion of the colon.

A unique tumor measuring 8 × 8 × 5 mm and composed of adenoma, adenocarcinoma and mixed carcinoid‐adenocarcinoma arising in the ascending colon is reported. The mixed carcinoid‐adenocarcinoma, in which adenocarcinomatous and carcinoid components intermingled, originated in the mucosa, penetrated the muscularis mucosa and extended into the submucosa. Immunohistochemically, carcinoid cells were positive for neuroendocrine markers and adenocarcinoma cells were intracytoplasmicly positive for carcinoembryonic antigen. Ultrastructurally, membrane‐bound electron dense granules varying in shape, size and electron density were detected in the cytoplasm of carcinoid cells. No mutations of p53 and k‐ras genes were detected in adenomatous, adenocarcinomatous or mixed carcinoid‐adenocarcinoma components. The morphological appearances of the present case strongly suggests the histogenesis of this tumor in an adenoma‐adenocarcinoma‐carcinoid tumor sequence.

Analysis of genetic alterations associated with DNA diploidy, aneuploidy and multiploidy in gastric cancers.

Objective: Recent studies have shown a close association between DNA ploidy status (diploidy, aneuploidy and multiploidy) identified by the crypt isolation technique and specific genetic alterations in colorectal carcinomas. However, such an association has not been elucidated for gastric tumors, even though they share common genetic features with colorectal carcinomas. In the present study, we established an association between DNA ploidy status and genetic alterations in gastric cancer. Method: The DNA ploidy status of gastric tumors was classified as diploid, aneuploid or multiploid using the crypt isolation technique, which allows isolation of pure tumor crypt from tumor tissue. Crypt isolation combined with DNA cytometric sorting, polymerase chain reaction assay using 26 microsatellite markers and direct sequencing of the p53 gene were used to detect allelic imbalances [loss of heterozygosity (LOH) or allelic loss], microsatellite imbalance (MSI) and mutation of p53 in 54 gastric cancers (13 diploid, 12 aneuploid, 29 multiploid). Result: Diploid tumors showed few genetic alterations, including allelic imbalances and p53 mutations. In contrast, aneuploid tumors and multiploid tumors (in particular, aneuploid populations of multiploid tumors) exhibited multiple genetic alterations, including allelic imbalances and p53 mutations. In addition, the frequencies of genetic alterations observed in the corresponding diploid fractions of multiploid tumors were relatively higher than in diploid tumors. MSI was commonly observed in diploid, aneuploid and multiploid carcinomas. Conclusions: The present results indicate that in gastric carcinomas, diploid tumors are generally non-LOH and MSI, whereas aneuploid and multiploid tumors are associated with LOH and MSI, suggesting that the genetic profile of these carcinomas is dependent on the tumor’s ploidy status.

Analysis of microsatellite alterations in gastric carcinoma using the crypt isolation technique

The crypt isolation technique was used to analyse loss of heterozygosity (LOH) and microsatellite instability (MSI) in gastric carcinomas (36 intestinal type, 17 solid type, and 23 diffuse type) using a polymerase chain reaction assay. Increased LOH frequencies and fractional allelic losses (FAL) were observed in samples prepared using the crypt isolation technique compared with those isolated by the conventional method. A significant increase in LOH was found at several chromosomal loci, and significant differences in FAL were found in patients with intestinal‐ and solid‐type tumours. There was no difference in the frequency of MSI using either technique. In samples prepared by the crypt isolation technique, significant allelic losses (≥50%) were observed at most loci tested in intestinal‐ and solid‐type tumours, but not in diffuse‐type tumours. Significant losses of some of these loci are novel findings for gastric cancer. FAL values were significantly higher in intestinal‐ and solid‐type tumours than in diffuse‐type tumours. MSI‐high was observed in intestinal‐ (17%) and solid‐type (12%) tumours. The results suggest that the crypt isolation technique is useful for accurate allelic loss analysis in gastric carcinoma and that LOH and MSI are more common in intestinal‐ and solid‐type tumours than in diffuse‐type tumors. Copyright

Tumor budding at the invasive front of colorectal cancer may not be associated with the epithelial-mesenchymal transition

Tumor budding is thought to reflect the epithelial-mesenchymal transition (EMT). However, the molecular mechanism linking tumor buds and the EMT remains unclear. Here, we examined the induction of tumor budding and EMT and their association with EMT-related proteins (ZEB1, TWIST, SNAIL, and SLUG) in colorectal cancer (CRC). Immunohistochemical expression of pan-cytokeratin was examined for identification of tumor budding in 101 CRCs. Grading of tumor budding was classified into low- and high-grade groups. Tissue microarray was conducted to identify tumor budding sites. The expression of E-cadherin, ZEB1, TWIST, SNAIL, and SLUG was examined in areas of tumor budding and the surrounding tumor stroma using a double-immunostaining method. Specifically, pan-cytokeratin and EMT-related proteins were assessed by double immunostaining. Low or no expression of E-cadherin was found in areas of tumor budding. Moreover, ZEB1, TWIST, SNAIL, and SLUG were not expressed in regions of tumor budding. However, the expression level of ZEB1 in the stromal cells surrounding tumor budding was significantly more frequent than that of TWIST, SNAI, and SLUG. In addition, the expression of EMT-related proteins in surrounding stromal cells was significantly greater in areas of high-grade tumor budding than in low-grade areas. Our present results suggest that EMT-related proteins play a minor role in forming tumor buds. In addition, our findings suggest the existence of subtypes of stromal cells in CRC with phenotypical and functional heterogeneity.

Analysis of allelic imbalances at multiple cancer-related chromosomal loci and microsatellite instability within the same tumor using a single tumor gland from colorectal carcinomas

Genetic changes related to colorectal carcinomas are accumulated in individual tumor glands during disease progression. Microsatellite allelic analysis of individual tumor glands from 30 colorectal carcinomas using a polymerase chain reaction (PCR) assay coupled with crypt isolation was used to detect intratumoral genetic heterogeneity, the sequence of allelic imbalances (AIs) and the microsatellite instability status of single tumor glands during neoplastic progression. In addition, the CpG islands methylated phenotype (CIMP) status was examined using a methylation‐specific PCR method. The specimens were divided into 2 groups: a pooled gland sample, which was composed of more than 50 tumor glands, and a single tumor gland sample. The latter consisted of 10 single tumor glands, which were obtained from the same tumor separately. Most colorectal carcinomas (27 of 30 tumors) examined were heterogeneous for at least one genetic alteration, with from 2 to 7 genotypically different subclones detected per tumor. In 12 of the 27 heterogeneous tumors, it was possible to define the order of genetic alterations during the tumor progression. By analyzing multiple single tumor glands within the same tumor, we found that various subclonal expansions were seen within the same tumors. Finally, the AI pattern of single tumor glands was not correlated with CIMP status. Most carcinomas appeared to have a heterogeneous composition. This may have resulted from the successful progression of one clone that had different AIs in many chromosomal regions. This suggests that knowledge of the different genotypes of multiple single tumor glands may help clarify the process of tumor progression.

Well-differentiated neuroendocrine tumor of the breast with recurrence due to needle tract seeding

Dear Editor, Recently, percutaneous imaging-guided core needle biopsy (CNB) ensuring a high degree of diagnostic accuracy and minimal invasiveness has been widely practiced as an alternative to surgical biopsy [1]. However, the procedure itself can, very rarely, contribute to disease recurrence [1, 2]. The WHO classifies mammary carcinomas with neuroendocrine (NE) features as a special tumor entity, representing <1 % of invasive breast carcinomas, and recognizes three subtypes: (i) NE tumor (NET), well-differentiated; (ii) NE carcinoma, poorly differentiated; and (iii) invasive carcinoma with NE differentiation [3, 4]. Herein, we describe the first case of a mammary NE cancer (well-differentiated NET) showing intramammary relapse related to needle implantation. A 60-year-old postmenopausal Japanese woman presented with slight skin retraction in the upper inner portion of the right breast. Ultrasonography revealed an irregular, hypoechoic right breast tumor with an echogenic halo and posterior attenuation. Systemic CT detected no other suspicious lesions. We performed ultrasound-guided 16-G automated CNB of the breast mass after obtaining informed consent, and the histological diagnosis was (ductal) carcinoma. The cut surface of the lumpectomy specimen contained a poorly delimited, grey-whitish and focally brownish-red, solid tumor, measuring 12×10 mm in size. Histologically, this tumor was composed of invasive growing carcinoma cells in solid and/or trabecular clusters with a highly vascular fibrovascular stroma and focal hemorrhage (Fig. 1). Carcinoma cells were polygonal or, occasionally, spindle-shaped with finely granular cytoplasm and ovoid nuclei with a finegranular chromatin pattern (Fig. 1a). Six mitotic figures were counted in 10 high-power fields. In situ carcinoma components were locally observed near invasive cancer nests. Neither lymphatic nor vascular infiltration was detected. Lateral, including nipple-side, margins were negative for cancer. On the other hand, we noted small foci of scarring with fat necrosis and hemosiderin-laden macrophages in the subcutaneous tissues away from the main tumor (Fig. 2a) and identified sporadic epithelial clusters showing cancer cell morphologies within and around the scar tissues (Fig. 2b, c). No metastases were identified in the four excised right axillary lymph nodes. T. Kawasaki (*) :A. Sato :M. Suzuki : R. Sugimoto :Y. Mue : N. Uesugi :K. Ishida : T. Sugai Department of Molecular Diagnostic Pathology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka, Iwate 020-8505, Japan e-mail: tomonori@yamanashi.ac.jp

Renal pelvic cancer with spleen invasion arising in horseshoe kidney; a case report

A 75-year-old man presented with horseshoe kidney and hydronephrosis. He had a history of cerebral infarction that had been treated with an antiplatelet drug. His body mass index (BMI) was 18.8 (kg/m2). He noticed asymptomatic gross hematuria three times within the previous three years. At each of the first two times, no apparent malignancies were detected. However, the third urine cytology examination revealed possible carcinoma. Pyuria was also detected using urinalysis. Enhanced computed tomography (CT) imaging showed a solid mass 50 mm in diameter in the left renal pelvis, and the mass had directly invaded the spleen (Fig. 1aec). Retrograde pyelography showed no filling defect, and a separate urine cytology examination revealed no malignancy. Therefore, we performed a CT-guided biopsy of the left renal pelvic mass; the

Neural cell adhesion molecule (CD56)-positive B cell lymphoma of the urinary bladder

CD56, the neural cell adhesion molecule (NCAM), is a member of the immunoglobulin superfamily and is associated with cell-to-cell adhesion and migration.1 Among haematological malignancies, CD56 expression has been described mainly in NK/T cell lymphoma, plasma cell myeloma and acute myeloid leukaemia, and rarely in B cell lymphomas, accounting for no more than 0.5% of all B lymphomas.2–8 Malignant lymphoma constitutes <1% of bladder neoplasms and low-grade mucosa-associated lymphoid tissue (MALT) type is most frequent.9 Herein, we describe the first case of primary CD56-positive B cell lymphoma (diffuse large B cell lymphoma, DLBCL) of the urinary system. The patient, a 60-year-old Japanese woman, presented with recurrent cystitis. Cystoscopy revealed a mass lesion in the urinary bladder. On MRI, this lesion appeared as a sessile tumour protruding into the bladder lumen at the posterior wall, with destruction of the muscularis propria. These images suggested an invasive urothelial carcinoma. Systemic CT, especially of lymph nodes, detected no other suspicious lesions. We performed transurethral biopsy of the bladder tumour after obtaining informed consent. Histologically, medium to large neoplastic cells with high nuclear/cytoplasmic ratios showed diffuse and/or relatively cohesive proliferations (figure 1A, B). Centrally located, ovoid or irregular-shaped nuclei had a finely dispersed chromatin pattern, occasionally with prominent nucleoli (centroblastic variant). Mitotic figures were numerous (98 per 10 high-power fields). …

Recoverin-associated retinopathy secondary to Warthin tumor of parotid gland

PurposeTo present a case of photoreceptor degeneration associated with a benign Warthin tumor of the parotid gland.Case reportA 57-year-old man visited our clinic complaining of blurred vision in both eyes. His best-corrected visual acuity was 0.07 in the right and 0.04 in the left eyes. All components of the full-field electroretinograms (ERGs) were reduced in both eyes. The focal macular ERGs were extinguished in both eyes, which was consistent with the deterioration of the outer retina in optical coherence tomographic images. Positron emission tomography showed 18F-fluorodeoxy glucose accumulation in the left parotid gland. Parotidectomy was performed, and the histopathology of the specimen had features compatible with a Warthin tumor without malignancy. Western blot analysis of the patient’s sera detected an antibody against recoverin. In addition, the tumor tissue had an aberrant expression of recoverin.ConclusionThe findings in this case indicate that recoverin-associated retinopathy can develop secondary to a benign Warthin tumor.