Toshiharu Maeda

Malignant peripheral nerve sheath tumor of the pancreas with perineurial cell differentiation.

The authors report a malignant peripheral nerve sheath tumor (MPNST) that developed in the body of the pancreas of a 76-year-old woman. The well-demarcated tumor, 4.5 x 3.5 cm in size, was composed of spindle-shaped cells arranged in a storiform pattern or sweeping fascicles. Ultrastructurally, the tumor cells had elongated cytoplasmic processes with numerous pinocytotic vesicles, and were covered with discontinuous basal lamina-like substances. Immunohistochemically, tumor cells were diffusely positive for epithelial membrane antigen, vimentin, and CD34, but negative for S-100 protein and Leu 7. It was therefore concluded that the tumor was a MPNST with perineurial cell differentiation. Primary MPNST of the pancreas is extremely rare and the immunohistochemical and ultrastructural studies are necessary for its diagnosis.

CALCIFYING FIBROUS PSEUDOTUMOR : AN ULTRASTRUCTURAL STUDY

To clarify the pathogenesis of calcification in calcifying fibrous pseudotumor (CFT), the lesion arising in the chest wall of a 16-month-old boy was ultrastructurally investigated. Fibroblasts were surrounded by large amounts of collagen fibrils. The dystrophic and psammomatous calcifications were observed as electron-dense amorphous masses and laminated bodies, respectively, within the cytoplasm of fibroblasts and in the collagenous stroma. The degeneration of cytoplasm seemed to be an initial event of intracytoplasmic calcification. Extracellular calcified substances often abutted to fibroblasts. Fibroblasts may play an important role in both intracellular and extracellular calcifications of CFT.

Immunohistochemical and Fluorescence In Situ Hybridization Studies on Noninvasive and Invasive Extramammary Paget’s Disease

To determine useful immunohistochemical markers for tumor cells in extramammary Paget’s disease (EMPD), immunohistochemical (IHC) examinations in 17 patients with EMPD, including 4 patients with dermal invasion, were performed. Among the antibodies examined, cytokeratin 7 (CK7) and CK19 were strongly positive for both intraepidermal and dermally invasive tumor cells in all patients. CAM5.2 and mucin 1 (MUC1) were also good markers. Although IHC examination revealed positive for HER-2 in 4 EMPD patients with dermal invasion, 4 out of 13 noninvasive patients were IHC negative. Fluorescence in situ hybridization (FISH) study revealed negative results for HER-2 gene amplification in 8 IHC positive patients, including each 4 patients of both noninvasive and dermal invasive cases. Our results show that besides CK7, CK19 is another favorable marker of tumor cells of EMPD. Four patients with dermal invasion were strongly positive for HER-2, although negative results were obtained in the FISH study. Further investigations are required to confirm the results of the FISH study.

Visual assessment of Ki67 using a 5-grade scale (Eye-5) is easy and practical to classify breast cancer subtypes with high reproducibility

Aims Personalised breast cancer therapy requires pathological characterisation of tumours. The proliferative index, based on Ki67, is pivotal, but a standard method has not been established. Here we look for an easy and practical way to evaluate Ki67. Methods Immunohistochemical staining of estrogen receptors, progesterone receptors, HER2 and Ki67 (MIB-1) was performed on resected specimens from 406 primary invasive ductal carcinomas. Ki67 labelling index (LI) from manual counting was compared with visual assessment using a 5-grade scale (Eye-5). Next, 10 pathologists evaluated 100 samples with marked hot spots by using Eye-5. Another 100 samples without marking were also assessed by eight pathologists. One year later, two pathologists reviewed 222 cases with Eye-5. Prognosis was analysed among estrogen receptor-positive cases with postoperative endocrine therapy. Results Eye-5 showed good correlation to LI. All 136 cases of score 4–5 had LI >20% and all 56 cases of score 1 had LI<20%, which means that manual counting was not necessary for about half of the cases. Interobserver and intraobserver variability was low even when a hot spot was not fixed. Eye-5 also correlated with histological grade and lymph node metastasis. Combining Eye-5 and histological grade created a new algorism to predict LI, which allows 80% of all cases (74% of luminal cases) without manual counting. Cases of Eye-5 score 1–2 had significantly better survival than score 3–5. Conclusions Visual assessment of Ki67 by a 5-grade scale (Eye-5) is fast, easy, and reliable with acceptably low interobserver and intraobserver variability. Eye-5 can replace LI in many luminal tumours, and is a strong candidate as a standard method of evaluating Ki67.

The Role of Computer-Aided 3-Dimensional Analytic Tools and Virtual Microscopy in the Investigation of Radiologic-Pathologic Correlation

To cope with recent advances in radiologic imaging technology, a corresponding method for pathomorphologic demonstration should be developed to promote better understanding of radiologic-pathologic correlation. We attempted to obtain gross and microscopic images by using a 3-dimensional analytic tool and virtual microscopy and to link these images with multidetector computed tomography images. Surgically resected specimens were sliced to a thickness of 3 mm, and the digital images of each slice were 3-dimensionally reconstructed with RATOC TRI/3D SRF II software. Histology slides were digitized by using virtual microscopy with an Olympus VS-100. We obtained clear gross pathologic images in arbitrary cut sections of organs, and it was possible to rotate these 3-dimensional images at any angle. Furthermore, we created synchronous cut-section movies of computed tomography and gross pathologic images. Subsequently, we switched from these cut-section movies to virtual microscopy images by clicking on the hyperlink button to observe radiologic-pathologic correlation.

Expression of p63 immunostaining in liquid-based cytology (BD SurePath) of breast fine-needle aspiration

We performed p63 immunostaining to detect myoepithelial cells on BD SurePath liquid‐based cytology (LBC) slides and examined whether this improved the diagnostic accuracy in breast fine‐needle aspiration cytology (FNAC).

HER2-Positive Metaplastic Spindle Cell Carcinoma Associated with Synchronous Bilateral Apocrine Carcinoma of the Breast

Apocrine carcinoma, which is strictly defined as over 90% of tumor cells showing apocrine differentiation, is a rare variant of breast cancer. Here we report an uncommon case in which apocrine carcinomas developed concurrently in both breasts; in addition, a sarcomatoid spindle cell lesion was coincident in the right breast. Both apocrine carcinomas were immunohistochemically negative for estrogen receptor (ER) and progesterone receptor (PgR), but diffusely positive for androgen receptor (AR), GCDFP-15, and HER2. The presence of intraductal components in bilateral carcinomas and the absence of lymph node metastasis suggested that they were more likely to be individual primary lesions rather than metastatic disease. The spindle cell lesion showed a relatively well-circumscribed nodule contiguous with the apocrine carcinoma. HER2 oncoprotein overexpression was observed not only in the apocrine carcinoma, but also in the spindle cell lesion. Since the spindle cell component was intimately admixed with apocrine carcinoma and had focal cytokeratin expression, we diagnosed it as metaplastic spindle cell carcinoma, which was originated from the apocrine carcinoma. To our knowledge, this is the first case report of a patient with synchronous bilateral apocrine carcinomas coinciding with metaplastic carcinoma.

A case of matrix-producing breast carcinoma.

背景:metaplastic carcinomaの一亜型であるrnatrix-producing carcinomaを経験したので報告する.症例:77歳, 女性, 平成12年2月右乳房腫瘤を自覚し近医受診. 腫瘤が増大傾向のため当院外科に紹介された. 穿刺吸引細胞診では, 粘液様背景に小集塊, 一列状配列を示す2相性の欠如した細胞塊が散見され粘液癌を疑った. 組織診では, 粘液様基質内に小型の腫瘍細胞が索状ないしは小胞巣を形成する比較的細胞成分の豊富な部分と, 間質が軟骨で細胞成分の乏しい部分を認め, matrix-producing carcinomaと診断した.結語:細胞診で粘液と考えていた背景の一部に軟骨様細胞を認めた. 軟骨様細胞を認めた場合は本疾患も念頭に置く必要があると思われる.