Mutational analysis of PI3K/AKT and RAS/RAF pathway activation in malignant salivary gland tumours with a new mutation of PIK3CA.

The phosphoinositide 3-kinase (PIK3)/v-akt murine thymoma (AKT) oncogene pathway and the RAS/RAF pathway are involved in regulating the signalling of multiple biological processes, including apoptosis, metabolism, cell proliferation, and cell growth. Mutations in the genes within these pathways are frequently found in several tumours. The aim of this study was to investigate the frequency of mutations in the PIK3CA, BRAF, and KRAS genes in cases of malignant salivary gland tumours. Mutational analysis of the PIK3CA, KRAS, and BRAF genes was performed by direct sequencing of material from 21 patients with malignant salivary gland tumours who underwent surgery between 1992 and 2001. No mutations were found in the KRAS exon 2, BRAF exon 15, or PIK3CA exon 9 genes. However, an unpublished mutation of the PIK3CA gene in exon 20 (W1051 stop mutation) was found in one case of adenocarcinoma NOS. The impact of this mutation on the biological behaviour of the tumour has yet to be explored, however the patient with adenocarcinoma NOS harbouring this mutation has survived for over 20 years following surgery despite a high stage at presentation. Further studies with more homogeneous patient cohorts are needed to address whether this mutation reflects a different clinical presentation and may benefit from targeted treatment strategies.

Merkel cell carcinoma of unknown primary site.

Merkel cell carcinoma is an uncommon and aggressive primary neuroendocrine skin malignancy which mostly affects the extremities and the head and neck region of elderly patients. Merkel cell carcinoma occurs with increased frequency in sun-exposed areas, in individuals exposed to arsenic and in immunosuppressed patients. Many patients with Merkel cell carcinoma present with other malignancies, mainly skin cancers. Characteristic features are frequent recurrences and regional and distant metastases. Mortality rates range from 20 to 65 per cent. The mainstay of treatment is surgery, with wide local excision, and adjuvant radiotherapy is usually administered. Merkel cell carcinoma of unknown primary site is rare, and the majority of the few cases described have not been from head and neck areas. We present a case of Merkel cell carcinoma of unknown primary site, with upper neck and distant metastases.

Fatal liver infarction after transjugular intrahepatic portosystemic shunt procedure.

Hepatic infarction is a rare disease. We describe here a cirrhotic patient with end-stage renal failure and recurrent tense ascites with fatal hepatic infarction after transjugular intrahepatic portosystemic shunt (TIPS) procedure. Abdominal ultrasound, radionuclide liver scan, abdominal computed tomography scan, and finally liver biopsy established the diagnosis. The mechanism causing the infarct is not clear. However, as the infarct appeared after the patient had an episode of shock and disseminated intravascular coagulation, it could well be that the concomitant hepatic arterial insufficiency contributed to the infarct. Physicians should be aware of this possible catastrophic complication.

[Giant lesions in multiple sclerosis--a diagnostic challenge].

Multiple sclerosis is the most common demyelinating disease of the central nervous system affecting young adults, in which destruction of the axon myelin sheath disturbs signal transduction. The disease course is usually remitting and relapsing, but sometimes there is steady neurological deterioration. The diagnosis depends mainly on an adequate clinical history and neurological examination. Evoked potentials, elevated cerebrospinal fluid gamma globulin with oligoclonal bands, and imaging studies, mainly magnetic resonance imaging (MRI), also contribute to the diagnosis. Multiple sclerosis may occasionally present as a mass lesion that clinically and radiologically is indistinguishable from a brain tumor. We present 2 cases of giant tumefactive lesions, proven by brain biopsy to be of demyelinating nature.

[Sclerosing mesenteritis--an unusual cause of abdominal pain].

Sclerosing mesenteritis (SM) is rare and fewer than 300 cases had been reported up to 1997. We describe a 29-year-old woman who had abdominal pain for 1 year and presented with a palpable abdominal mass. The diagnosis of SM was made only after diagnostic laparoscopy and biopsy of the peritoneum.

Kaposi's sarcoma after lung transplantation in a Sephardic Jewish woman.

One of the four types of Kaposi's sarcoma (KS), KS after organ transplantation under immunosuppression, is a well-known entity and has been abundantly described in renal, heart and liver recipients. We report the second case of cutaneous KS after lung transplantation, under regular immunosuppression, in a Sephardic Jewish woman. This case, when added to the other 10 cases of posttransplantation KS reported from Israel, all being Sephardic Jews, indicates that in Israel, Sephardic Jews are at higher risk than Ashkenazi Jews to develop posttransplantation KS. This observation should be added to the well-known increased risk of Ashkenazi Jews to develop classic KS. Moreover, in Israel Ashkenazi Jews develop classic KS at higher rates than Sephardic Jews. This apparent discrepancy in the ethnic distribution between Sephardic and Ashkenazi Jews in classic versus posttransplantation KS may shed light on the pathogenesis of KS in general.

Acute neutrophilic dermatosis induced by all-trans-retinoic acid treatment for acute promyelocytic leukemia.

All-trans-retinoic acid (ATRA) is considered the recommended induction treatment for acute promyelocytic leukemia (APL). Although the dermatological side effects associated with ATRA treatment are relatively common, acute neutrophilic dermatosis (Sweet's syndrome) has only been rarely reported. We describe such a case who responded to chemotherapy and not to low doses of corticosteroids.

The additive miotic effects of dapiprazole and pilocarpine.

BACKGROUND: Since dapiprazole on alpha-adrenergic agent, produces miosis by paralyzing the dilator muscle, and pilocarpine, a parasympathetic drug, causes miosis by affecting the sphincter, we speculated that the two drugs might have additive effects. METHODS: The additive miotic actions of pilocarpine 2% and dapiprazole 0.5% were evaluated by comparing the effects of two drugs given together and alone on the reversal of mydriasis induced by tropicamide (0.5%) and phenylephrine (10%) in one eye each of 60 healthy volunteers. RESULTS: Dapiprazole and pilocarpine together induced miosis significantly faster than each drug alone, showing additive effects. CONCLUSION: Co-administration of dapiprazole and pilocarpine at the end of the eye examination will induce fast pupillary constriction, which might be useful in preventing the development of an acute attack of angle-closure glaucoma in patients with anatomically narrow angles.