A case report of intracholecystic papillary neoplasm of the gallbladder resembling a submucosal tumor.

BACKGROUND: Intracholecystic papillary neoplasm (ICPN) is defined as papillary tumors detected macroscopically in the gallbladder. We report a case of ICPN which exhibited the atypical form like a submucosal tumor. CASE PRESENTATION: A 70-year-old man was admitted to our hospital because of hepatic disorder. Computed tomography and magnetic resonance imaging showed irregular thickening of the wall within the gallbladder fundus. Because the lesion might have been malignant, we performed laparoscopic cholecystectomy and liver bed resection. Macroscopic findings showed the mucosal surface of the tumor was smooth, and its form was similar to that of a submucosal tumor. Histopathological examination revealed papillary tumors within the mass with low-grade dysplasia; therefore, we diagnosed ICPN. CONCLUSION: In the present case, ICPN was resembling a submucosal tumor macroscopically because the tumors arose into the Rokitansky-Aschoff sinus and the adenomyomatous hyperplasia was merged with the ICPN. It is necessary to consider the possibility of tumor lesions within adenomyomatous hyperplasia.

[Low-Dose and Interval Administration of Imatinib in a Patient with Liver Metastasis of the Gastrointestinal Stromal Tumor of the Stomach - A Case Report].

A 69-year-old woman underwent proximal gastrectomy with distal pancreatectomy and splenectomy for a gastrointestinal stromal tumor of the stomach.Adjuvant imatinib was administered for a year.Two years after resection of the tumor, liver metastasis in S8 was detected.Therefore, imatinib was re-administered at 300mg/day.After a year of re-administration, the patient suffered muscle cramps in the hands, and therefore imatinib was administered with intervals, such as 4 weeks administration and 4 weeks rest.Re -administration of imatinib was effective and her liver metastasis decreased in size.It was not detected with CT after 1 year and 4 months and remained in complete response(CR)for 3 years and 8 months.After she suffered a brain infarction, imatinib administration was stopped for 4 months.Consequently, the liver metastasis was detectable in S8 again.This clinical course suggested that low-dose and interval administration of imatinib is effective in the treat- ment of GIST.

Torsion of the gallbladder diagnosed by magnetic resonance cholangiopancreatography.

Torsion of the gallbladder is a rare entity that is difficult to diagnose preoperatively, the principal differential diagnosis being cholecystitis. The condition occurs most often in the elderly. Although its etiology is unknown, the presence of a redundant mesentery is a prerequisite for torsion. Computed tomography, ultrasound, and magnetic resonance cholangiopancreatography can provide important diagnostic clues. Torsion of the gallbladder occurs when it twists axially, with subsequent occlusion of bile or blood flow. Therefore, prompt surgical treatment is necessary in order to prevent necrosis and perforation. In the present study, we report a case of torsion of the gallbladder diagnosed by magnetic resonance cholangiopancreatography. This condition was successfully treated by laparoscopic cholecystectomy.

Enforced expression of Bcl-2 partially restores cell numbers but not functions of TCRgammadelta intestinal intraepithelial T lymphocytes in IL-15-deficient mice.

IL-15 knockout (KO) mice have severely reduced numbers of TCRgammadelta intestinal intraepithelial T lymphocytes (i-IEL), suggesting requirements of IL-15 signaling in the development or maintenance of i-IEL. To determine an involvement of survival signals via Bcl-2 in IL-15-mediated homeostasis of TCRgammadelta i-IEL, we introduced a bcl-2 transgene into IL-15 KO mice. In situ apoptosis of TCRgammadelta i-IEL was decreased in Bcl-2 transgenic (Tg) x IL-15 KO mice compared with IL-15 KO mice. The enforced expression of Bcl-2 partially restored the numbers of TCRgammadelta i-IEL in IL-15 KO mice. However, effector functions of TCRgammadelta i-IEL, including cytokine production and cytotoxic activity, were not recovered in Bcl-2 Tg x IL-15 KO mice. Importantly, TCRgammadelta i-IEL in Bcl-2 Tg x IL-15 KO mice expressed a reduced level of eomesodermin, a transcription factor critical for effector functions of NK cells and CD8(+) T cells. Similar to the case of TCRgammadelta i-IEL, enforced expression of Bcl-2 restored the numbers but not the functions of NK cells in IL-15 KO mice. These results suggest that Bcl-2-mediated survival signal is involved in the IL-15-mediated homeostasis of TCRgammadelta i-IEL and NK cells, but other signals from IL-15 are critical for inducing transcription factors, such as eomesodermin for their effector functions.

IL-15 regulates CD8+ T cell contraction during primary infection.

During the course of acute infection with an intracellular pathogen, Ag-specific T cells proliferate in the expansion phase, and then most of the T cells die by apoptosis in the following contraction phase, but the few that survive become memory cells and persist for a long period of time. Although IL-15 is known to play an important role in long-term maintenance of memory CD8+ T cells, the potential roles of IL-15 in CD8+ T cell contraction are not known. Using an adoptive transfer system of OT-I cells expressing OVA257-264/Kb-specific TCR into control, IL-15 knockout (KO) and IL-15 transgenic (Tg) mice followed by challenge with recombinant Listeria monocytogenes expressing OVA, we found that the survival of CD44+CD62L-CD127- effector OT-I cells during the contraction phase is critically dependent on IL-15. In correlation with the expression level of Bcl-2 in OT-I cells, the number of OT-I cells was markedly reduced in IL-15 KO mice but remained at a high level in IL-15 Tg mice during the contraction phase, compared with control mice. In vivo administration of rIL-15 during the contraction phase in IL-15 KO mice inhibited the contraction of effector OT-I cells accompanied by up-regulation of Bcl-2 expression. Furthermore, enforced expression of Bcl-2 protected the majority of effector OT-I cells from death in IL-15 KO mice after infection. These results suggest that IL-15 plays a critical role in protecting effector CD8+ T cells from apoptosis during the contraction phase following a microbial infection via inducing antiapoptotic molecules.