MPLW515L mutation in acute megakaryoblastic leukaemia.

The thrombopoietin receptor gene (MPL) is expressed in megakaryocytes and exhibits the gain of function point mutation W515K/L in approximately 5% of patients with primary myelofibrosis/idiopathic myelofibrosis (PMF) representing one subtype of the chronic myeloproliferative disorders (myeloproliferative neoplasm). A series of primary and secondary acute myeloid leukaemias (AML) with megakaryoblastic phenotype and myelofibrosis unrelated to PMF (n=12) was analysed for the MPL(W515K/L) mutation by pyrosequencing. In three cases (25%), MPL(W515L) was found and in two of these a combination with trisomy 21 or the Philadelphia chromosome occurred.

[Metastatic placental site trophoblastic tumor. Diagnosis after pneumothorax].

Placental site trophoblastic tumor (PSTT) is a rare, mostly benign tumor, which in 10-15% of cases shows a malignant behavior. The case of a 35 year old woman with pulmonary metastasis of a PSTT is reported. This finding was incidental in an atypical lung-resection due to pneumothorax.

[Incidental chorangiocarcinoma. Case report, immunohistochemistry and theories of possible histogenesis].

We describe the third case world-wide of a chorangiocarcinoma, a tumour with an abnormal trophoblast proliferation in combination with a hypervascular chorangiosis of the villous stroma. The lesion was an incidential finding by a healthy 31-year-old woman, gravida 1, para 1 when the pregnancy was terminated at 34 weeks gestation because of fetal distress and intrauterine growth restriction. Hormonal levels were within the normal range.

[Leiomyosarcoma of the spermatic cord. A case report with review of the literature].

The case of a 68-year-old man with leiomyosarcoma of the spermatic cord is reported. Radical orchiectomy with high ligature of the cord was performed. Pathological examination including immunohistochemistry demonstrated a leiomyosarcoma which seemed to arise from a spermatic cord vessel.

[Ectopic meningioma of the tonsil].

To our knowledge this is the first reported case of a primary extracranial meningioma located in the palatine tonsil. Immunohistochemical investigation of the tumour showed coexpression of vimentin and neuron-specific enolase (NSE). No staining was found with antibodies against cytokeratins KL1, 13/10, 8 and 18, epithelial membrane antigen EMA and melanoma protein (HMB-45).