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A 46-year-old woman visited our outpatient clinic complaining of dull right hypochondrial pain. Ultrasonography revealed four cysts in the right lobe of the liver. Arteriography and CT could not determine whether these cysts were benign or malignant. Because one of these cysts contained chocolate-colored fluid, amebic abscess was suspected, and the cyst was drained. No amebae were found in the cultured exudate, and fresh bleeding continued; therefore, laparotomy was performed. A tumor was present on the surface of the liver. Right lobectomy was performed. The resected specimen contained one nonepithelialized cyst which was invaded by surrounding cholangiocellular carcinoma and three epithelialized cysts. Preoperative diagnosis of this kind of cholangiocellular carcinoma seems to be very difficult. Recently cholangiocellular carcinoma associated with developmental cysts has been classified as a new entity different from cystadenocarcinoma. Cholangiocarcinoma, which belongs to this group, seems to deserve special attention.  相似文献   
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OBJECTIVE: Vasopressin (AVP) is reported to be an important factor for regulating cortisol secretion in patients with Cushing's syndrome due to ACTH-independent macronodular adrenocortical hyperplasia (AIMAH). Recently, there have been several case reports of subclinical Cushing's syndrome due to AIMAH, in which the pathophysiological role of AVP has been unknown. The aim was to conduct an extensive investigation of AVP in the autonomous secretion of cortisol in subclinical Cushing's syndrome due to AIMAH. PATIENTS AND MEASUREMENTS: Five cases of AIMAH with subclinical Cushing's syndrome underwent prospective study including physical examination, imaging (MRI, CT and 131I-adosterol scintigraphy) and endocrinological evaluation that comprised basal plasma cortisol levels and urinary excretions of steroid metabolites, a dexamethasone suppression test and an AVP stimulation test. In case 1, left adrenalectomy was performed and the pathological diagnosis of AIMAH was established. An in vitro experiment using the cultured AIMAH adrenal cells was conducted to investigate cortisol secretion and expression of the V1-AVP receptor, mRNA by RT-PCR. RESULTS: All five cases were discovered incidentally to have bilateral adrenal nodules. Imaging by MRI and CT revealed large multinodular lesions in both adrenal glands, which showed positive uptake on 131I-adosterol scintigraphy. Although the basal values of plasma cortisol and urinary excretions of steroid metabolites were within normal limits, autonomous secretion of cortisol was assumed to occur because of lack of suppression during dexamethasone suppression. The five patients had no overt signs of Cushing's syndrome, and they were therefore diagnosed with subclinical Cushing's syndrome due to AIMAH. In all five patients, AVP stimulated cortisol secretion in vivo, whereas desmopressin acetate failed to affect cortisol secretion. In case 1, AVP stimulated cortisol secretion from cultured AIMAH adrenal cells, but this secretion had no relationship with cAMP production. In addition, over-expression of V1-AVP receptor mRNA in AIMAH tissue was determined by RT-PCR. CONCLUSION: Patients with subclinical Cushing's syndrome due to AIMAH commonly exhibit cortisol responsiveness to AVP, and this is probably mediated through activation of overexpressed V1-AVP receptors.  相似文献   
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Background

For almost 30 years, transanal endoscopic microsurgery (TEM) has been the mainstay treatment for large rectal lesions. With the advent of endoscopic submucosal dissection (ESD), flexible endoscopy has aimed at en bloc R0 resection of superficial lesions of the digestive tract. This systematic review and meta-analysis compared the safety and effectiveness of ESD and full-thickness rectal wall excision by TEM in the treatment of large nonpedunculated rectal lesions preoperatively assessed as noninvasive.

Methods

A systematic review of the literature published between 1984 and 2010 was conducted (Registration no. CRD42012001882). Data were integrated with those from the original databases requested from the study authors when needed. Pooled estimates of the proportions of patients with en bloc R0 resection, complications, recurrence, and need for further treatment in the ESD and TEM series were compared using random-effects single-arm meta-analysis.

Results

This review included 11 ESD and 10 TEM series (2,077 patients). The en bloc resection rate was 87.8 % (95 % confidence interval [CI] 84.3–90.6) for the ESD patients versus 98.7 % (95 % CI 97.4–99.3 %) for the TEM patients (P < 0.001). The R0 resection rate was 74.6 % (95 % CI 70.4–78.4 %) for the ESD patients versus 88.5 % (95 % CI 85.9–90.6 %) for the TEM patients (P < 0.001). The postoperative complications rate was 8.0 % (95 %, CI 5.4–11.8 %) for the ESD patients versus 8.4 % (95 % CI 5.2–13.4 %) for the TEM patients (P = 0.874). The recurrence rate was 2.6 % (95 % CI 1.3–5.2 %) for the ESD patients versus 5.2 % (95 % CI 4.0–6.9 %) for the TEM patients (P < 0.001). Nevertheless, the rate for the overall need of further abdominal treatment, defined as any type of surgery performed through an abdominal access, including both complications and pathology indications, was 8.4 % (95 % CI 4.9–13.9 %) for the ESD patients versus 1.8 % (95 % CI 0.8–3.7 %) for the TEM patients (P < 0.001).

Conclusions

The ESD procedure appears to be a safe technique, but TEM achieves a higher R0 resection rate when performed in full-thickness fashion, significantly reducing the need for further abdominal treatment.  相似文献   
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