Search

The Yamamoto-Kohama (Y-K) mode of invasion is a useful indicator of the prognosis of squamous cell carcinoma (SCC) of the oral cavity. We have previously reported that the Y-K mode of invasion is related to lymph node metastasis in esophageal SCC. Therefore, to clarify the relationship between the Y-K mode of invasion and survival rate, we histologicaly evaluated specimens obtained by esophagectomy from patients who had not received induction therapy. The results indicated that the overall survival rate of patients with esophageal SCC was significantly lower in the Y-K 4D group. In addition, significantly lower expression of involucrin protein was observed in pStage III cases than in pStage II cases. As a consequence of the poor prognosis of pStage III SCC, it was suggested that involucrin expression was correlated with survival rate. In conclusion, the Y-K mode of invasion and involucrin expression are considered to be informative prognostic indicators in patients with esophageal SCC.

A 59-year-old diabetic male presented with transient motor aphasia and monoparesis of the right upper limb. Brain CT scan showed a low density area in the left subdural space with a mild midline shift. Magnetic resonance (MR) T2-weighted and fluid-attenuated inversion recovery (FLAIR) imagings revealed homogenous hyperintensity with a hypointense web-like structure in the subdural hematoma. Cervical MR angiography showed no abnormal lesion at the bifurcation of the bilateral common carotid arteries. Conventional cerebral angiography showed an avascular, crescent, space-occupying mass over the left hemisphere without an etiologic lesion of cerebral ischemia. CT perfusion imagings indicated reduced cerebral blood flow (CBF) and prolonged mean transit time (MTT) in the left middle cerebral artery territory underneath the subdural hematoma. No epileptic discharge was found in electroencephalogram. Operative findings indicated that the hematoma was encapsulated with thickened outer and inner membranes including paste-like materials, and the brain surface was intact. Postoperative CT perfusion imagings revealed normal CBF and MTT. The pathophysiological mechanism which the chronic subdural hematoma produces the transient neurological deficit is still uncertain. The mechanical pressure of the hematoma on the neighboring cerebral vessels may cause impairment of blood flow leading to cerebral ischemia and paralysis of function. Our case indicated the transient neurological deficits attributed to a decreased CBF around the subdural hematoma and a change in pressure exerted by the hematoma during changes of head position and increased blood viscosity.

Evaluation of early metabolic changes in metastatic brain tumors after Gamma Knife radiosurgery was performed by long-echo (TR, 2000ms; TE, 136ms; 128-236 acquisitions) volume-selected single-voxel proton magnetic resonance spectroscopy (MRS). Eighty-five brain metastases in 81 patients were investigated before treatment and 16-18h thereafter. Standard metabolic ratios, namely N-acetylaspartate (NAA)/creatine (Cr), phosphorylcholine/glycerophosphorylcholine (Cho)/Cr, NAA/Cho, lactate (Lac)/Cr, and mobile lipids (Lip)/Cr, were calculated, and comparison of their values before and after irradiation was done. No volumetric changes of any neoplasm were found in any case on the next day after treatment. At the same time, significant reduction of Cho/Cr (P < 0.001) and NAA/Cr (P < 0.01) ratios on the proton MRS of the tumor was disclosed. Reduction of Cho/Cr ratio was significantly more prominent in neoplasms with higher pretreatment Cho/Cr ratios (P < 0.001) and heterogeneous contrast enhancement (P < 0.01). Reduction of NAA/Cr ratio was predominantly determined by its pretreatment value (P < 0.001). The observed decrease of Cho/Cr ratio probably reflects inhibition of proliferative activity and early apoptotic cell loss, whereas reduction of NAA/Cr may result from radiation-induced modulation of neuronal activity in the peritumoral brain tissue. Serial proton MRS represents a valuable diagnostic tool for evaluation of metabolic changes in intracranial neoplasms after radiosurgical treatment.

Gamma knife radiosurgery was carried out for spontaneous CCF (carotid-cavernous sinus fistula) in 8 patients (1 male and 7 females), and its results were reported. The ages ranged from 48 to 74 years with a mean of 60.6 years. As initial treatment before radiosurgery, embolization was carried out except in one patient, and radiotherapy was used in two patients. Six patients were in the category of Barrow's type D, and two patients were in the category of Barrow's type B. As it contained the fistula, the lateral wall of the cavernous sinus was irradiated with 8-14.5 Gy (mean 10.8 Gy). As a result, complete obliteration of CCF was confirmed by DSA in seven of the eight patients between 6 and 18 months after radiosurgery. There were no side effects observed during a follow-up period of 8 to 116 months. Although the main treatment for spontaneous CCF is intravascular surgery at present, gamma knife radiosurgery is a useful adjuvant treatment for the residual CCF after embolization.