Magnetic resonance imaging assessment of tumorous lesions in the floor of the mouth: case reports and review of the literature

Objectives Magnetic resonance (MR) imaging may provide some information as to the extent and tissue characteristics of a cancerous mass, but the imaging features of lesions in the floor of the mouth have not been sufficiently clarified. MR imaging features of tumescent lesions in this region were characterized, and the differential diagnoses are discussed. Methods MR images of 12 patients with tumescent lesions in the floor of the mouth (three patients with squamous cell carcinoma, two with adenoid cystic carcinoma, one with hemangioma, one with schwannoma, one with lipoma, and four with ranula) were reviewed. The literature on the imaging features of tumescent disease in the floor of the mouth was searched using the Medline database. Results Six types of tumescent lesions in the floor of the mouth are presented. The differential diagnosis through a review of the references is discussed. Malignant tumors were demonstrated as ill-defined masses. MR images were good at showing the internal structures, such as fluid, hemorrhage, fat, nerves, calculus (phlebolith), cholesterol, and keratin, as different signal intensities. Therefore, MR images gave clues for the differential diagnosis. Conclusion MR images presented the distinctive features or the extent of the lesions and were therefore considered useful for a more accurate diagnosis prior to treatment.     

Elevated alpha1-acid glycoprotein in gastric cancer patients inhibits the anticancer effects of paclitaxel,effects restored by co-administration of erythromycin

Paclitaxel (PTX) which easily elutes into ascites is widely used to treat gastric cancer patients with peritoneal carcinomatosis (PC), but clinical outcomes are suboptimal. Increased concentrations of α1-acid glycoprotein (AGP), an important drug-binding protein, have been reported in the plasma and ascites of cancer patients. This study sought to clarify whether AGP binds to PTX and alters its anticancer effects. AGP concentrations were measured in the serum and ascites of gastric cancer patients with PC and in the serum of healthy volunteers. The in vitro effects of AGP and AGP plus erythromycin (EM) on PTX were evaluated by MTT assays in the gastric cancer cell lines. We also measured AGP concentrations in the ascites of PC model mice and examined the effects of EM plus PTX on PC. The mean AGP concentrations in the serum and ascites of gastric cancer patients with PC were 1524 and 834 μg/mL, respectively, higher than the mean AGP concentration of 650 μg/mL observed in the sera of healthy volunteers. AGP > 400 μg/mL significantly suppressed the cell growth inhibitory effect of PTX in vitro, but the co-administration of EM restored it. Elevated AGP concentrations were observed in the ascites of PC model mice. Administration of PTX alone did not markedly diminish PC, whereas co-administration of PTX and EM significantly reduced PC (p = 0.011). AGP is an important regulatory factor modulating the anticancer activity of intraperitoneal PTX. The co-administration of PTX and EM may be effective in treating gastric cancer patients with PC.     

Transplantability and sensitivity to natural killer cells of aclarubicin-resistant murine lymphoma

DBA/2 mice implanted i.p. with an aclarubicin (ACR)-resistant subline of L5178Y cells survived 4- to 5-fold longer than those with the parental cells; and animals with the Adriamycin- or bleomycin-resistant subline displayed an intermediate survival period. The i.p. treatment of mice with cyclophosphamide markedly enhanced i.p. growth of the ACR-resistant cells, suggesting that a certain host defense mechanism participates in the lower transplantability. In vitro, the ACR-resistant subline showed much higher sensitivity to natural killer cells. The i.p. pretreatment with anti-asialo-GM1 antibody markedly reduced the mean survival period of mice implanted i.p. with the ACR-resistant cells, suggesting that natural killer cells play an important role in the defense against transplantation of the ACR-resistant cells.     

Photoradiation therapy of experimental brain tumor

Malignant tumors retain hematoporphyrin to a much greater extent than do normal tissues and can be destroyed by exposure to light. To utilize this mechanism in the treatment of malignant brain tumor, we investigated the antitumor effect of photoradiation on rat and mouse glioma, utilizing hematoporphyrin administration and cold light irradiation. In vitro study of rat glioma (EA285), the tumor cells which were exposed to hematoporphyrin and light irradiation showed marked degeneration in a short time, though no change was found in the control groups of hematoporphyrin administration alone and of light irradiation alone. The subcutaneously transplanted gliomas of rat and mouse also showed the growth inhibition after treatment of hematoporphyrin and light irradiation, though they grew up again. Histological degeneration by this treatment reached about 7 mm depth in the tumor. It was made clear that the effect on gliomas was induced by photosensitization and not by heat. From these results it is concluded that photoradiation therapy would be a great means for adjuvant therapy for malignant brain tumor.