RESUMO
The oral rexinoid bexarotene (Targretin) is widely used for treatment of cutaneous T-cell lymphomas (CTCL). We recently reported the first case of adult T-cell leukemia/lymphoma (ATLL) that responded rapidly to combination therapy of bexarotene and interferon (IFN)-alpha2b with complete clinical response. We demonstrated that bexarotene induced apoptosis of the patient's malignant peripheral blood T-cells in vitro. However, our patient developed skin and nodal relapse 180 days after starting treatment. We now demonstrate that his peripheral blood malignant T cells became resistant to bexarotene-induced apoptosis. We investigated potential mechanisms that may cause aberrations in the retinoid X receptor (RXR) subunits, RXR-alpha and RXR-beta, to account for these findings. Sequence analysis did not reveal acquisition of mutations in the genes encoding RXR-alpha and RXR-beta by resistant cells. We assessed RXR-alpha and RXR-beta expression by Western blot analysis and found that resistant cells had significantly decreased RXR-alpha expression compared with pretherapy bexarotene-sensitive cells. Our findings indicate that reduced expression of the RXR-alpha receptor subunit may represent a mechanism for resistance to bexarotene in T-cell malignancies.
Assuntos
Resistencia a Medicamentos Antineoplásicos , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Receptor X Retinoide alfa/deficiência , Tetra-Hidronaftalenos/farmacologia , Bexaroteno , Humanos , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Recidiva , Receptor X Retinoide alfa/análise , Neoplasias Cutâneas , Linfócitos T/efeitos dos fármacos , Tetra-Hidronaftalenos/uso terapêuticoRESUMO
A 57-year-old female presenting with acute-onset paraplegia was referred for magnetic resonance imaging (MRI) of cervico-dorsal spine. On MRI, multiple tortuous dilated vessels were noted in the epidural space with long segment cord compression and imaging features of compressive myelopathy. Associated small acute cervico-dorsal epidural hematoma was also noted in the same region. Computed tomography (CT) angiography was performed subsequently which revealed post-ductal coarctation of aorta with multiple arterial collaterals in the chest wall and spinal canal. An extensive review of English language literature pertaining to the clinical presentations of adult aortic coarctation revealed only few reports of acute compressive myelopathy due to spinal epidural collateral vessels. Further, presentation at such a late age has not been reported before. In the present case, apart from a hypertrophied anterior spinal artery and perispinal collaterals, an anterior epidural hematoma was an additional important factor in the causation of myelopathy.
RESUMO
Priapism, prolonged painful erection of the penis, is a urological emergency. Untreated, the patient can end up with impotence. Various methods have been described for its treatment but the initial management remains conservative. This study presents our experience with the use of sedation followed by an ice-cold saline enema in the management of priapism.
Assuntos
Crioterapia , Enema , Priapismo/terapia , Cloreto de Sódio/uso terapêutico , Adolescente , Adulto , Humanos , MasculinoRESUMO
Malignant peripheral nerve-sheath tumor (MPNST) is a high-grade malignant tumor of ecto-mesenchymal origin comprising approximately 10% of soft-tissue sarcomas. They tend to occur associated with neurofibromatosis or sporadically. Here we report a MPNST at an extremely rare location and behavior causing disappearance of the entire kidney. Patient evaluation included clinical, biochemical and radiological studies before treatment. Histological study revealed the rare diagnosis. Patient was asymptomatic at six-month follow-up after treatment.