Synovial cysts of the temporomandibular joint: an immunohistochemical characterization and literature review.

Synovial cysts of the temporomandibular joint (TMJ) are very rare, and to date, only 12 cases of a synovial cyst in the TMJ region have been reported in the literature. In this paper, we present the clinicopathological and immunohistochemical characteristics of one such lesion affecting a 48-year-old woman, presented with a mass in the left preauricular region. We describe the usefulness of immunohistochemical analysis for recognizing the synovial lining, which allowed for clear differentiation between ganglion and synovial cysts. Immunohistochemical analyses can be used to diagnose synovial cysts with certainty; however, using at least two markers is advisable to distinguish the two existing synovial cell subtypes. Our findings indicate that synovial cysts of TMJ possess an internal lining dominated by type B (fibroblast-like) synoviocytes.

Gastrointestinal stromal tumors (GISTs): CD117, DOG-1 and PKCθ expression. Is there any advantage in using several markers?

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the digestive tract. Expression of CD117, DOG1 and PKCθ was investigated immunohistochemically in a series of 99 paraffin-embedded GISTs in order to determine the sensitivity and diagnostic value of these markers. KIT exons 9, 11, 13 and 17 and PDGFRA exons 12 and 18 were amplified by PCR and sequenced. A total of 94/99 (94%) GISTs stained positive for CD117, 81/99 (82%) for PKCθ and 90/99 (91%) for DOG-1. A significant correlation was noted between CD117 and DOG-1 expression (p=0.0001). All three markers were expressed in 74% (73/99) of GISTs. Of the five CD117-negative cases, two were PKCθ-negative/DOG1-negative and had mutations in KIT exon 11. Two were PKCθ-positive/DOG1-positive and had mutations in PDGFRA (one each in exons 12 and 18), and one was DOG1-negative/PKCθ-positive, with a PDGFRA exon 18 mutation. The most sensitive marker was CD117, followed by DOG-1 and PKCθ. Although PKCθ was less sensitive, and its staining is more challenging and difficult to interpret, the use of this marker is highly recommended, particularly in CD117-negative/DOG-1-negative GISTs.

Differential activation of MAPK and PI3K/AKT/mTOR pathways and IGF1R expression in gastrointestinal stromal tumors.

AIM: To characterize the differentially-activated mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K/Akt/mTOR) pathways in mutant (m) and wild-type (wt) GISTs and to investigate the role of insulin-like growth factor 1 receptor (IGF1R) expression. MATERIALS AND METHODS: Ninety-nine paraffin-embedded gastrointestinal stromal tumors (GISTs) were selected. CD117, IGF1R, phospho-ERK1/2, phospho-Akt, p70S6, eukaryotic initiation factor 4E-binding protein-1 (4EBP1) and pS6 expression were investigated using immunohistochemical methods. KIT exons 9, 11, 13 and 17 and platelet derived growth factor receptor alpha (PDGFRA) exons 12 and 18 were amplified by PCR and sequenced. RESULTS: Significant differences were found in the expression of phospho-ERK1/2 between mGISTs and wtGISTs. Complex evaluation of all PI3K/Akt/mTOR pathway markers revealed greater activation in mGISTs, particularly in PDGFRA-mutated GISTs. No significant correlation was observed between IGF1R expression and either mutational status or pathway activation. CONCLUSION: There appears to be no MAPK pathway activation in wtGISTs. Tumors harboring PDGFRA mutations tended to use the PI3K/Akt/mTOR signaling pathway. Most adult GISTs, irrespective of mutational status, displayed no IGFR1 expression; tumors positive for IGFR1 showed no preferential activation of the MAPK or AKT pathways.

Dermatomyositis and flagellate erythema.

Flagellate erythema, described by Moulin in 1970 as reminiscent of the lesions produced by flogging and by other authors as zebra-like lesions, was noted first in association with bleomycin treatment, but later occasionally reported in relationship with dermatomyositis, mostly from Japan. It is characterized by linear, erythematous, cutaneous streaks, pruriginous or painful, arising on an oedematous background and disappearing spontaneously over several weeks. So far, fewer than five cases have been reported in association with dermatomyositis, but we now present a further one.

[Chronic eosinophilic pneumonia. Presentation of 2 cases]. / Neumonía eosinofílica crónica. Presentación de dos casos.

Two cases of patients with chronic eosinophilic pneumonia are presented. We highlight the possibility to obtain the diagnosis without lung biopsy, as well as the spectacular response to steroid treatment which has to be continued for a long period in order to avoid relapses.

[Participation of the colon in the compensatory process after massive intestinal resection. An experimental study in rats]. / Participacion del colon en el proceso de adaptacion compensadora tras la reseccion intestinal masiva. Estudio experimental en ratas.

The colon participation in the adaptation process after massive intestinal resection (R.I.M.) has been rarely studied. This is an experimental study in rats to know the morphological modifications to the colon after R.I.M. of small bowel. A total of 90 Wistar rats weighing 200-250 grams were used, in two groups. Twenty animals constituted group I (control) and 70 were submitted to resection of 85-90 per 100 of the small bowel (group II, R.I.M.). Radiologic and weights controls has been performed. To end of study (four months),a the animals were sacrificed to obtain histologic samples of the large bowel for structural and morphometric studies. The results of this study to confirm the colon participation in the compensatory adaptation process after R.I.M. of small bowel.

Histological appearances of oesophagus, antrum and duodenum and their correlation with symptoms in patients with a duodenal ulcer.

Clinical data and histology from the oesophagus, gastric antrum, and duodenum were collected from 36 patients undergoing surgery for duodenal ulcer. Gastritis was present in 94% of the patients (25% of atrophic type), oesophagitis in 72% and duodenitis in 39%. Abnormal biopsies were present from all three sites in 33% of the patients. Only one patient showed three normal biopsies. The low incidence of duodenitis does not support the theory that duodenitis is part of the same spectrum as duodenal ulcer. Heartburn was related to the presence of gastritis (100%) and oesophagitis (76%) but not to duodenitis (52%). No relationship was found between the length of history, severity of pain, and histological abnormalities.

Transplacental carcinogenesis with radioactive phosphorus.

1 An attempt was made to produce a model of osteogenic sarcoma using 32P transplacentally. 2 Fetal tissues appeared to be resistant to irradiation as no tumour was induced at an increased frequency in treated animals. 3 Tumours that normally occur in our strain (Sprague-Dawley rats) showed a clear tendancy to occur earlier in post-natal life in treated animals compared with controls.

[Symptomatic renal angiomyolipoma associated with tuberous sclerosis]. / Angiomiolipoma renal sintomático asociado a esclerosis tuberosa.

A kidney angiomyolipoma associated with tuberous sclerosis is described. This rare tumor is sometimes asymptomatic and is found at autopsy, but in some cases it may be confounded with a malignant tumor, as in the present case. The authors consider the angiomyolipoma as a choristoma rather than as a true neoplasm.

Blood group antigens in vascular tumours. Evaluation of the immunoperoxidase technique.

Determination of blood group isoantigens A, B and H, was performed in benign and malignant vascular tumours of the skin and subcutaneous tissue, using the immunoperoxidase technique. No differences were noted between benign haemagioendotheliomas from children or adults: neither tumour showed the presence of antigens in intercapillary cells. Reactive conditions such as angiolymphoid hyperplasia with eosinophilia showed an intense positive reaction to blood group substances of the endothelial proliferative cells. In malignant tumours no relationship between tumour differentiation and loss of blood group isoantigens was seen. Cases of Kaposi's sarcoma did not show antigens in spindle cells or capillaries but in medium sized vessels variable preservation or loss of blood group isoantigens was found.

Intravascular papillary endothelial hyperplasia in the skin and subcutaneous tissue.

Twenty-four cases of Intravascular Papillary Endothelial Hyperplasia (IPEH) have been studied. IPEH comprises approximately 2% of benign and malignant vascular tumours of the skin and subcutaneous tissue. This peculiar tumour-like process lacks specific clinical characteristics and its diagnosis must be based on microscopic examination. Histologically is is characterised by a papillary proliferation of endothelial cells forming vascular channels, commonly associated with thrombus and in some cases simulating angiosarcoma.--Follow-up of 10 cases indicates a benign clinical course.

Vegetant intravascular hemangioendothelioma of the skin. Report of 3 cases with a critical pathogenetic study.

3 cases of cutaneous vegetant intravascular hemangioendothelioma are presented, 2 of them corresponded to a pure form, whilst the other arose in a pyogenic granuloma. All lesions behaved in a benign fashion. In some cases these may mimic an angiosarcoma (Masson's pseudoangiosarcoma). The endothelial proliferation, which characterizes the lesion, is considered as a reactive phenomenon secondary to fibrin deposits originating from the destruction of the vascular walls of a hemangioma.