Possible linkage between specific histological structures and aberrant reactivation of the Wnt pathway in adamantinomatous craniopharyngioma

This study concerns the significance of nuclear/cytoplasmic expression of beta-catenin and mutation of the beta-catenin gene in craniopharyngiomas. Fourteen adamantinomatous type and one squamous papillary type craniopharyngiomas were studied. Histologically, 13 of 14 adamantinomatous type craniopharyngiomas showed typical features, ie mixtures of 'palisading cells', 'stellate cells', and 'ghost cells'. In addition, 'whorl-like arrays' of epithelial cells were frequently observed in the areas of stellate cells. On immunohistochemistry, all typical adamantinomatous type craniopharyngiomas showed nuclear/cytoplasmic expression of beta-catenin predominantly in cohesive cells within the whorl-like arrays and in cells transitional towards ghost cells, where immunoreactivity for Ki-67 was almost absent. The cohesive cells in the whorl-like arrays also demonstrated loss of cytokeratin isoform expression. Using direct sequencing of amplified nucleic acids, nine of the 13 typical adamantinomatous type craniopharyngiomas with nuclear beta-catenin accumulation showed heterozygous one-base substitution mutation of the beta-catenin gene. The other unusual adamantinomatous type and squamous papillary type craniopharyngiomas showed no obvious nuclear/cytoplasmic beta-catenin immunoreactivity and no mutation of the beta-catenin gene, suggesting molecular heterogeneity. These findings suggest that the pathogenesis of typical adamantinomatous type craniopharyngioma is associated with abnormalities of Wnt signalling that act as a morphogenetic signal towards whorl-like arrays and ghost cells rather than as simple proliferation stimuli.     

Proliferative activities of tumor stromal cells play important roles in tumor thickness and progression of T3 ulcerative-type colorectal cancer

The central depressed area thickness (tumor thickness) of colorectal cancers is an important prognostic parameter for colorectal cancer patients. We examined whether the proliferative activities of tumor and stromal components play important roles in the increase of tumor thickness and the progression of colorectal cancers. Colorectal cancers were classified into thin and thick groups according to tumor thickness. The proliferative activities of fibroblasts and endothelial cells were immunohistochemically evaluated in 157 T3 ulcerative-type colorectal cancers by CD31/MIB-1 (anti-Ki-67 antigen) double staining. The MIB-1 labeling index was estimated as the percentage of fibroblasts with positive nuclei. The CD31-positive microvessels lined by MIB-1-positive endothelial cells were assessed. The proliferative microvessel index was defined as the percentage of proliferative microvessels relative to all microvessels. The fibroblast MIB-1 labeling index was the only parameter significantly associated with tumor thickness ( P=0.049). High fibroblast MIB-1 labeling indices showed significant correlation with tumor recurrence in the thin group ( P=0.020). High proliferative microvessel index was a significant parameter of tumor recurrence in the thick group ( P=0.003) in multivariate analyses. This study strongly suggests that proliferative activities of stromal components are useful parameters of tumor biology and of prognosis for T3 ulcerative-type colorectal cancer patients.     

Loss of membranous Ep-CAM in budding colorectal carcinoma cells.

Tumor budding is a histological feature that reflects loss of adhesion of tumor cells and is associated with locoregional metastasis of colorectal carcinoma. Although nuclear localization of beta-catenin is associated with tumor budding, the molecular mechanism remains largely elusive. In this study, we hypothesize that the epithelial cell adhesion molecule (Ep-CAM) is involved in tumor budding. In order to address this question, we performed immunohistochemistry on Ep-CAM using three different antibodies (monoclonal antibodies Ber-ep4 and 311-1K1 and a polyclonal antibody) and a double staining on beta-catenin and Ep-CAM. In addition, Ep-CAM mRNA was monitored with mRNA in situ hybridization. Subsequently, we determined the effect of Ep-CAM staining patterns on tumor spread in rectal cancer. In contrast to the tumor mass, budding cells of colorectal carcinoma displayed lack of membranous but highly increased cytoplasmic Ep-CAM staining and nuclear translocation of beta-catenin. mRNA in situ hybridization suggested no differences in Ep-CAM expression between the invasive front and the tumor mass. Importantly, reduced Ep-CAM staining at the invasive margin of rectal tumor specimens (n=133) correlated significantly with tumor budding, tumor grade and an increased risk of local recurrence (P=0.001, P=0.04 and P=0.03, respectively). These data demonstrate abnormal processing of Ep-CAM at the invasive margin of colorectal carcinomas. Our observations indicate that loss of membranous Ep-CAM is associated with nuclear beta-catenin localization and suggest that this contributes to reduced cell-cell adhesions, increased migratory potential and tumor budding.     

Immunohistochemical analyses of β-catenin and cyclin D1 expression in giant cell tumor of bone (GCTB): A possible role of Wnt pathway in GCTB tumorigenesis

Giant cell tumor of bone (GCTB) is a benign neoplasm but occasionally shows local recurrence, and histologically consists of osteoclast-like giant cells (GC) and stromal mononuclear cells (SC), which are capable of proliferation and osteoblastic differentiation. Activation of Wnt signaling can induce osteoblast differentiation and osteoclastgenesis during bone resorption process. This study analyzed the profiles of β-catenin and cyclin D1 expression in GCTB to elucidate an involvement of Wnt pathway in tumorigenesis. We performed immunohistochemistry for β-catenin, cyclin D1, and Ki-67 in 16 GCTB tumors, including 5 recurrent cases that were surgically resected. All 16 cases of GCTB displayed β-catenin, cyclin D1, and Ki-67 expression. Immunoreactivity for β-catenin was observed in nuclei of SC and GC. Cyclin D1 immunoreactivity was found mainly in nuclei of GC, while Ki-67 immunoreactivity was restricted to nuclei of SC. The nuclear β-catenin labeling index (LI) in both SC (60.6 vs. 41.8%, p=0.074) and GC (41.7 vs. 20.1%, p=0.095) was higher in recurrent tumors than in primary tumors in all the 4 cases. However, Ki-67 LI in SC (18.8 vs. 19.9%, p=0.851) and cyclin D1 LI in GC (55.4 vs. 70.1%, p=0.225) were not higher in recurrent tumors than in primary tumors. Our results suggested activation of Wnt/ β-catenin pathway in GCTB tumorigenesis. Since cyclin D1 in GC was never associated with the expression of the well-known proliferative marker Ki-67, cyclin D1 expression might play a role in GC formation instead of promoting cell proliferation during GCTB tumorigenesis. Importantly, it was suggested that the nuclear β-catenin staining level might be associated with tumor recurrence in GCTB.     

脑肿瘤患者胰岛素样生长因子-1水平的研究

目的探讨血清胰岛素样生长因子（IGF）-1水平与脑肿瘤的关系,垂体瘤、颅咽管瘤手术与血清IGF-1水平变化是否存在联系。方法检测193例脑肿瘤患者血清及61例术后相应患者血清IGF-1水平,用SPSS16．0统计软件进行分析。结果①恶性脑肿瘤组与良性脑肿瘤组间的差异有统计学意义（P〈0．05）,侵袭性垂体瘤组与非侵袭性垂体瘤组间差异有统计学意义（P〈0．05）;②颅咽管瘤手术前后血清IGF-1水平差异有统计学意义（P〈0．05）,侵袭性与非侵袭性垂体瘤手术前后血清IGF-1水平差异无统计学意义（P〉0．05）。结论①IGF-1在良性脑肿瘤和恶性脑肿瘤患者血清中表达的水平存在差异,可帮助临床对肿瘤的恶性程度作出早期的判断;②颅咽管瘤患者手术前后血清IGF-1水平存在差异,对患者的预后判断具有参考价值。     

Gastric fibromyxoma, a distinct entity of pure fibroblastic tumor--an ultrastructural study

A rare case of fibromyxoma arising in the stomach of a 78-year-old male is presented. A well-defined, encapsulated tumor measuring 27x17x8 cm showed a lobular growth in the submucosa and muscularis propria, with no association with the propria mucosa. Histologically, the tumor was characterized by a diffuse, widely spaced proliferation of small spindle, stellate and round cells with dendritic outlines with fibromyxoid stroma. Neither cellular atypia nor mitotic figures were observed. Immunohistochemically, the tumor was positive for vimentin and CD34 but negative for CD117, alpha-smooth muscle actin, muscle actin, desmin and S-100 protein. Ultrastructurally, the tumor cells had irregularly shaped nuclei and cytoplasm containing moderate amounts of mitochondria, rough endoplasmic reticulum, subplasmalemmal densities, and short interdigitating processes. These findings indicated the fibroblastic nature of the tumor. The patient was well without recurrence 20 months after surgery. It is important to recognize that gastric fibromyxoma is a distinct entity and to include it in the differential diagnosis of gastric mesenchymal tumors, as the tumors show a different clinical behavior and as limited surgery with local excision is possible.     

Primary intratesticular spindle cell tumors: interdigitating dendritic cell tumor and inflammatory myofibroblastic tumor

Spindle cell neoplasms arising in the testis are uncommon; most cases belong to the category of gonadal stromal tumors, and the presence of distinctive clinical and pathological features usually lead to a definitive diagnosis. In some instances, however, the diagnosis of these tumors can be challenging and special techniques are needed. The present study reports 2 unusual cases of primary intratesticular tumors showing a striking morphology, characterized by spindle to stellate cells in a lymphoid background. The diagnosis of interdigitating dendritic cell tumor and inflammatory myofibroblastic tumor was established in the 2 cases, and their probable origin in cells of the accessory immune system is discussed. Although both tumors share similar histological features, their immunohistochemical profiles were decisive for a definitive diagnosis.     

Outcome of postoperative intratumoral bleomycin injection for cystic craniopharyngioma

Total excision is a treatment of choice in preventing the relapse of craniopharyngioma, but for tumors involving an extensive area, it is often associated with an increased risk of complications. We have performed a partial or subtotal tumor removal followed by repeated injection of bleomycin into the remaining tumor through a subcutaneous reservoir as postoperative adjuvant therapy. A retrospective review of clinical, radiological, and surgical data was performed for 10 patients (5 males and 5 females; age, 3-65 yr; follow-up duration, 12-79 months) with cystic craniopharyngiomas. The measurements of lactate dehydrogenase (LDH) level at each aspiration were performed. The shrinkage and/or stabilization of tumor was initially noted in all cases. The recurrence of tumor was seen in 4 cases (40%). The decreased or increased level of LDH was interpreted as tumor shrinkage or recurrence, respectively. The transient toxic reactions were observed in 3 patients (30%). Our study demonstrates that postoperative bleo-mycin injection for cystic craniopharyngioma, although does not appear to eradicate the tumor, decreases and stabilizes the tumor size, when used as an adjuvant therapy in young patients.     

Plexiform fibrohistiocytic tumor of bone

Plexiform fibrohistiocytic tumor is an extremely rare soft tissue tumor with a low malignancy potential. The patient is usually a child or a young adolescent and the tumor is usually localized in the upper extremities. We report on a case of a 21‐year old male with a plexiform fibrohistiocytic tumor in the left fibula admitted to our hospital due to a swelling and pain in the left lower extremity. Radiologically a lytic lesion in the distal end of left fibula consistent with a non‐aggressive lesion with low biological activity was found. Treated with curettage, the specimen revealed plexiform proliferation of mononuclear histiocyte‐like cells, multinucleated osteoclast‐like cells, and spindle fibroblast‐like cells in variable proportions histopathologically. Immunohistochemical stains were positive for CD68 in scattered fashion in histiocytes and giant cells, and spindle like cells showed positivity for smooth muscle actin. Under electron microscopy, rough endoplasmic reticulum and collagen bundles in the spindle cells suggested fibroblastic differentiation. Also multiple large electron‐dense lysosomal granules in histiocytoid cells were found. Multinucleated giant cells exhibited osteoclast‐like appearance. All these findings suggested plexiform fibrohistiocytic tumor. Interestingly, the tumor was localized in bone. During the follow up for 27 months after the resection, there was no recurrence or metastasis.     

Ovarian myxoma. A study of two cases with long-term follow-up

Two cases of the so-called ovarian myxoma are reported. One was from a 13-year-old girl who had a 31-year follow-up and no evidence of recurrence. The second case, from a 65-year-old woman, recurred intraperitoneally, 19 years after the surgery. Both tumors were myxoid, with round to stellate cells. Immunohistochemical, electron microscopic (EM), and DNA flow cytometric (FCM) studies were performed on formalin-fixed, paraffin-embedded tissue of the second patient on both the primary tumor and the recurrence. Tumor cells expressed vimentin and were focally positive for desmin and myoglobin. EM findings suggested a fibroblastic differentiation. An aneuploid cell population was present in the recurrent tumor by DNA-FCM studies. Only four other cases of so-called ovarian myxoma were reported to date, and the follow-up does not exceed 18 months. The authors conclude that the presence of aneuploidy and the late recurrence of one of their cases suggest that certain ovarian myxomas might behave like low-grade sarcomas. The histogenesis of this tumor remains unsettled, but similarities were found with myxomas in other locations.     

Expression of E-cadherin in chordomas: diagnostic marker and possible role of tumor cell affinity

Chordoma is a relatively rare malignant bone tumor thought to arise from the remnants of the fetal notochord. Chordomas express epithelial cell markers such as cytokeratin and epithelial membrane antigen (EMA), which strongly suggests that the tumor cells grow via the mechanism of epithelial characterized cell-cell interactions. However, there are no known reports that have studied epithelial characterized cell-adhesion molecules such as E-cadherin or epithelial cell adhesion molecule (Ep-CAM) in chordomas. An immunohistochemical investigation was performed in seven cases of chordoma to determine the expression of pan-cytokeratin, Ep-CAM, and E-cadherin. Histological specimens showed the typical appearance of conventional chordoma but for two cases of chondroid chordoma. Cytokeratin was constantly expressed in conventional chordomas, but it was detected among a few cells with physaliphorous appearance in chondroid chordoma cases. Although no Ep-CAM expression was noted, E-cadherin was detected in most chordoma cells irrespective of histological subtypes. The expression of E-cadherin was negative among chondrosarcoma cells in this study as previously reported, and thus constant E-cadherin expression of chordoma cells suggests a role as a useful diagnostic marker to distinguish chondroid chordoma from chondrosarcoma. Furthermore, we speculate that E-cadherin may play a role in tumor cell adhesion and is also involved with histological and clinical features in chordomas.     

Phosphatase and tensin homologue and pituitary tumor-transforming gene in pituitary adenomas. Clinical-pathologic and immunohistochemical analysis

Pituitary tumor-transforming gene (PTTG) is also known to induce angiogenesis during pituitary tumorigenesis. It has not been clarified whether PTTG functions as a cytoplasmic or a nuclear protein. Pituitary tumor-transforming gene-1 is usually expressed in most pituitary tumors, and little is known about phosphatase and tensin homologue (PTEN). In our knowledge, it has not been studied in pituitary tumors. The aim of this study was to determine the correlation between proliferating cell nuclear antigen (PCNA) labeling index (LI), PTEN, and PTTG-1 immunoexpression in pituitary adenomas. Forty-five pituitary adenomas were included—46.7% were males and 53.7% were females. The mean age was 43.18 ± 9.42 years (27-70 years). For functional pituitary adenoma (PA), it was 41.92 ± 6.63, and for nonfunctional pituitary adenomas, it was 44.62 ± 11.85 (P = .003). Proliferating cell nuclear antigen LI range was 19.42 ± 5.49; in functional pituitary adenomas, it was 41.92 ± 6.63, and in nonfunctional adenomas, it was 44.62 ± 11.85 (P = .081). The PTEN immunoreaction was positive—weak in 21 (47%), moderate in 19 (42%), and strong in 5 (11%; P = .000). The PTTG-1 gene was positive—weak in 18 (41%), moderate in 19 (41%), and strong in 6 (13%; P = .000). When we correlated PTEN + PCNA, it was P =.004, and PTEN + PTTG-1, it was P = .019. And when we correlated PCNA + PTGG-1, it was P = .262. In our results, we observed higher expression of PCNA-LI and PTTG-1 and loss of expression of PTEN. Nonfunctional hypophysis adenomas presented a higher PCNA, PTTG-1, and PTEN expression than functional ones. There was no difference between single-hormone-producing hypophysis adenomas or multiple-hormone-producing ones. Necrosis and hemorrhage were associated with PTEN expression, whereas atypias and mitosis figures were associated to PTTG-1 expression.     

Odontogenic myxofibroma with HMGA2 overexpression and HMGA2 rearrangement

Odontogenic myxofibromas are variants of odontogenic myxomas that contain considerable amounts of collagen fibers in the myxoid stroma. Cytogenetic studies of odontogenic myxomas/myxofibromas have rarely been reported. This report describes the first case of an odontogenic myxofibroma presenting with HMGA2 protein overexpression and HMGA2 rearrangement in a 40-year-old woman. A 2.7-cm tumor in the premolar region of the right mandible was curettaged. There was no evidence of recurrence or metastasis at 12 months after the surgery. Histological examination revealed that the tumor comprised spindle or stellate cells with mild nuclear pleomorphism, abundant myxoid matrix and partly dense collagen fibers. Mitotic figures were rarely observed. Immunohistochemically, the tumor cells were diffusely positive for vimentin and HMGA2. Less than 1% of the tumor cells were positive for Ki-67. We detected split signals by interphase fluorescence in situ hybridization (FISH) in paraffin sections using HMGA2 break-apart probes. The breaks were certainly located within or near the HMGA2 gene. No rearrangement of the FUS gene was detected by FISH, implying discrimination from low-grade fibromyxoid sarcoma. It is suggested that HMGA2 rearrangement and HMGA2 protein overexpression may be associated with the tumorigenesis of odontogenic myxomas/myxofibromas, similar to the case for many other benign mesenchymal tumors.     

Fine structure of adrenocortical cells in adult male rhesus monkeys

Adrenals of ten mature male rhesus monkeys were studied by electron microscopy. Mitochondria had lamelliform cristae in the zona glomerulosa and tubular cristae in the zona fasciculata and zona reticularis. Agranular reticulum of tubular form was scarce in the zona glomerulosa but present in great abundance in the fasciculata and reticularis. The Golgi complex was prominent in the cells of the zona glomerulosa but poorly developed in the cells of the inner cortical zones. Zona fasciculata cells contained large, highly ordered “stacks” of granular endoplasmic reticulum which showed multiple connections with the random network of tubular agranular reticulum. In the reticularis, granular endoplasmic reticulum was present in more disordered, whorl-like arrays. Lipid droplets in the inner cortical regions were enveloped by tubules of agranular endoplasmic reticulum. Occasional sections showed these tubules ending blindly at or near the surface of the lipid droplets. This association was strongly suggestive of a functional relationship. Dense bodies varied in size and complexity of structure throughout the cortex. They were smallest and simplest in form in the zona glomerulosa; those in the zona reticularis were the largest and most complex.     

Fibroma of tendon sheath: a tumor of myofibroblasts. A clinicopathologic study of 18 cases

A clinicopathologic study of 18 cases of fibroma of tendon sheath included an immunohistochemical survey of 7 cases and an electron-microscopic examination of one. The age of the patients ranged from 1 to 77 years, with a median of 34 years. The most common site of the tumors was the finger (7 cases), followed by the knee (3), the hand (2), and the foot (2). The median greatest diameter of the tumor was 2 cm. The tumors were attached or closely related to the tendon or tendon sheath, and usually well circumscribed, and multinodular or lobulated. Microscopically, spindle or stellate tumor cells with fuchsinophilic cytoplasm were embedded in a dense fibrous stroma with scattered small blood vessels. Most tumor cells have immunoreaction products for actin in the cytoplasm with accentuation along the cell membrane. Ultrastructurally, many of the tumor cells proved to be myofibroblasts.     

The expression of Ep-CAM (17-1A) in squamous cell cancers of the lung

Immunotherapy trials using monoclonal antibodies 323/A3 and 17-1A that recognize Ep-CAM, including trials focused on cancer of the lung, currently are underway. Nevertheless, there have been few comprehensive evaluations of the expression of Ep-CAM in specific types of neoplastic processes, including cancer of the lung. The current study of 60 human subjects with squamous cell cancer (SCC) of the lung, selected at random, was undertaken (1) to examine the expression of Ep-CAM in SCC and associated uninvolved bronchial mucosa, bronchial epithelial hyperplasia, and dysplasia, and (2) to correlate the results with established prognostic indicators and survival of patients. In both the uninvolved bronchial mucosa and epithelial hyperplasia, the expression of Ep-CAM in luminal cells was significantly higher compared with its expression in the matched basal cells (P = .003, P < .0001, respectively). When Ep-CAM scores of basal and luminal cells present in uninvolved bronchial mucosa and epithelial hyperplasia were combined, we observed a statistically significant stepwise increase in Ep-CAM expression from uninvolved bronchial mucosa to epithelial hyperplasia to SCC, suggesting its involvement in malignant transformation of SCC. The expression of Ep-CAM was significantly higher in poorly to moderately differentiated SCC compared with well-differentiated SCC (P = .04). An increase in the expression of Ep-CAM with increasing size or local extent of the primary tumor approached statistical significance (P = .09). The expression of Ep-CAM increased significantly with increasing involvement of regional lymph nodes (P = .02). Similarly, the expression of Ep-CAM increased with the increasing TNM stages (P = .04). Kaplan-Meier Survival analysis using the same categorizations showed that increasing tumor size, nodal status, and stage were significantly associated with poor patient survival (P = .04, .01, .01, respectively). There was, however, no statistically significant association between patient survival and staining intensity of carcinomas for Ep-CAM. We conclude that expression of Ep-CAM increased during the progression of SCC of the lung and, therefore, may play a role in the carcinogenesis of this disease.     

Ultrastructure and immunohistochemistry of a fetal-type Leydig cell tumor.

A symptomless scrotal mass was removed from a 34-year-old man. The lesion was 7 cm in diameter and it was grossly a hemorrhagic cyst with indurated walls. By light microscopy tumor cell clusters and cords were seen infiltrating the testicle, tunica albuginea, and paratesticular tissue. In the immunohistochemical analysis the tumor cells were immunoreactive with anti-S-100 protein and anticarcinoembryonic antigen, but they did not express cytokeratin or alpha-fetoprotein as tested with paraffin sections. Tumor cell clusters were enveloped by a laminin-positive basement membrane. Electron microscopy revealed abundant smooth endoplasmic reticulum, lipid droplets, and membranous whorls in the cytoplasm. Lamellar whorled bodies were also seen in mitochondria, which contained tubulovesicular cristae. The presence of a well-developed, often multilayered basement membrane was confirmed at ultrastructural level. The activity of 3-beta-hydroxysteroid dehydrogenase suggested that the tumor cells were capable of androgen synthesis. The morphological features are reminiscent of fetal-type Leydig cells and are distinctly different from the Leydig cell tumors described so far.     

A successfully treated inflammatory myofibroblastic tumor of the mandible with long-term follow-up and review of the literature

Inflammatory myofibroblastic tumor (IMT) of the oral cavity is an extremely rare clinical and pathological disease entity. It was originally described in the lung but has recently been reported in various anatomic sites. We report such a case of inflammatory myofibroblastic tumor of the mandible in a 14-year-old girl. The patient presented with an aggressive ulcerative soft tissue mass of 3 months duration in the mandibular molar gingiva. Histologically, the lesion was composed of fibroblastic or myofibroblastic spindle cell proliferations with infiltrative margins in an inflammatory background. Immunohistochemically, the fibroblastic or myofibroblastic spindle cells were positive for vimentin, α-smooth muscle actin, and Ki-67 (MIB-1) but negative for desmin, pan-cytokeratin, S-100 protein, CD34, CD68, CD99, bcl-2, β-catenin, estrogen receptor, progesterone receptor, ALK-1, and p53. These spindle cells were focally and weakly Ki-67- (MIB-1-) positive. The MIB-1 labeling index was 5%. The results of in situ hybridization for Epstein-Barr virus-encoded-RNA were negative. The ratio of IgG4+/IgG+ plasma cells was about 10%. A pathological diagnosis of inflammatory myofibroblastic tumor was made. The postoperative course was uneventful, and the patient has had no recurrence in the 10-year follow-up period. Although no evidence of oral inflammatory myofibroblastic tumor recurrence or malignant transformation has been reported, it has been observed that in inflammatory myofibroblastic tumors of other regions, a prolonged follow-up is necessary after surgical resection. No other case of an IMT patient under 20 years of age has appeared in either the English or the Japanese literature.