Akira Taen

An anterograde and retrograde tract-tracing study on the projections from the thalamic gustatory area in the rat: distribution of neurons projecting to the insular cortex and amygdaloid complex.

Projections from the thalamic gustatory nucleus, i.e. the parvicellular part of the posteromedial ventral thalamic nucleus (VPMpc) to the forebrain regions were studied in the rat by the tract-tracing methods with anterograde tracer (biotinylated dextran amine, BDA) and anterograde/retrograde tracer (wheat-germ agglutinin-horseradish peroxidase, WGA-HRP). After BDA injection into the VPMpc, terminal labeling was observed in the insular cortex, amygdaloid complex, and fundus striati. The terminal labeling in the amygdaloid complex was distributed in dorsolateral area of the rostral part of the lateral amygdaloid nucleus and the rostral part of the lateral subdivision of the central amygdaloid nucleus. The terminal labeling in the central amygdaloid nucleus extended to the fundus striati. The retrograde tracing study with WGA-HRP revealed that the projection fibers from the VPMpc to the amygdaloid complex originated from the medial part of the VPMpc and also from the thalamic area medial to the VPMpc. In the rats injected with Fluoro-Gold and WGA-HRP, respectively into the insular cortex and amygdaloid complex, no double-labeled neuronal cell bodies were found in the VPMpc, although neurons labeled singly with Fluoro-Gold were intermingled with those singly labeled with WGA-HRP in the medial part of the VPMpc. The results indicated that VPMpc neurons projecting to the amygdaloid complex constituted a population different from VPMpc neurons projecting to the insular cortex.

Stages III and IV squamous cell carcinoma of the mouth: three-year experience with superselective intraarterial chemotherapy using cisplatin prior to definitive treatment.

Purpose: This study was designed to assess the 3-year experience with superselective intraarterial chemotherapy prior to definitive treatment for stages III and IV squamous cell carcinomas of the mouth.Methods: Twenty-two patients prospectively received superselective intraarterial chemotherapy using relatively low-dose cisplatin via a transfemoral approach. The locations of the tumors were the tongue (n=12), gingiva (n=5), buccal mucosa (n=2), hard palate (n=1), floor of the mouth (n=1), and lip (n=1). After intraarterial chemotherapy, 21 patients underwent surgery (n=14), radiation therapy (n=6), or both (n=1). The survival rate of 25 patients who underwent surgery with/without radiationtherapy until 1992 at Kumamoto University Hospital was also evaluated as a historical control. The survival curve was calculated with the Kaplan-Meier method, and the statistical difference between survival curves was determined with the generalized Wilcoxon test.Results: The overall response rate was 95% [complete response (tumor completely resolved), 24%; partial response (tumor reduction ≥50%), 71%]. Fifty-two intraarterial infusions were performed without any catheter-related complications. Mild and transient local toxicity such as edema or mucositis of the infused area was relatively common. One patient died of renal failure from cisplatin. After a median follow-up of 20 months (range 2–41 months), the estimated 3-year survival rate for patients who underwent intraarterial chemotherapy plus surgery was 91%. The survival of the patients who underwent intraarterial chemotherapy plus surgery tended to be longer than that of the historical control.Conclusions: Early tumor reduction without delay of subsequent treatments can be obtained by intraarterial chemotherapy while minimizing complications and possibly improving survival. Further investigations of long-term survival with larger series need to be performed.