A long-term follow-up study of minimally invasive Ivor Lewis esophagectomy with linear stapled anastomosis.

BACKGROUND: Minimally invasive esophagectomy (MIE) is increasingly performed to expect lower complication rate compared to open esophagectomy. Studies of minimally invasive Ivor Lewis esophagectomy (MIILE) with circular staplers have reported better outcomes compared to MIE with cervical anastomosis, but frequent anastomotic complications have also been reported. MIILE with linear staplers is a promising alternative, but the long-term functional and oncological outcomes are uncertain. METHODS: To evaluate the functional and oncological outcomes of MIILE with linear stapled anastomosis, a retrospective cohort study was performed in 104 patients who underwent MIILE with linear stapled anastomosis for esophageal malignant tumors. The primary endpoints were the overall complication and anastomotic leak rates. The secondary endpoints were late complications, overall and disease-free survival, and nutritional status at 6 and 12 months after MIILE. RESULTS: Anastomotic leak occurred in 4 patients (3.8%). The short-term complication rate of grade IIIb or higher was 6.7%. During a median 57-month follow-up period, anastomotic stricture occurred in one patient, 7 required hiatal hernia repair, and 2 underwent conduit revision surgery. The 5-year overall survival and disease-free survival rates were 69.3% and 59.5%, respectively. Status of reflux esophagitis at the time of most recent evaluation was grade N/A/B/C/D in 52/10/10/13/8 among 93 patients who had follow-up endoscopy. The mean body weight loss at 6 and 12 months after MIILE was 11.3 and 11.8% with maintenance of the serum albumin level. CONCLUSIONS: MIILE with linear stapled anastomosis is a safe procedure with a low anastomotic complication rate and favorable long-term functional and survival outcomes.

Pathogenic mechanisms of intestinal pneumatosis and portal venous gas: should patients with these conditions be operated immediately?

We aimed to histologically observe portal venous gas (PVG)-causing intestinal pneumatosis (IP) and evaluate pathogenic mechanisms and therapeutic strategies, including decisions on whether emergency surgery should be performed. Autopsy was performed in two cases of nonocclusive mesenteric ischemia (NOMI). We directly histologically observed the pathogenic mechanisms of IP caused by gas-producing bacteria and IP considered to be caused by mechanical damage to the intestinal mucosa. IP can be classified hypothetically into the following types according to pathogenesis: (1) infection, (2) rupture (damage) of the intestinal mucosa + increased intestinal intraluminal pressure, and (3) mixed type. In cases of IP caused by gas-producing bacteria or IP associated with intestinal wall damage extending beyond the mucosa to the deep muscular layer, emergency surgery should be considered. However, it is highly possible that patients who test negative for infection with gas-producing bacteria whose intestinal wall damage remains only in the mucosa can be conservatively treated.

[Remarkable tumor response to cisplatin plus gemcitabine therapy in a patient with recurrent gallbladder cancer - a case report].

We report a case of recurrent gallbladder cancer in which the patient's tumor showed a remarkable response to gemcitabine( GEM)plus cisplatin(CDDP)therapy. In January 2007, the patient underwent curative resection for gallbladder cancer (T2N1M0, Stage III), and tegafur/uracil was administered for a year as adjuvant chemotherapy. In September 2009, elevated serum CA19-9 levels were observed, and para-aortic lymph node swelling was seen on CT scans. In addition to the indications reported by Valle et al, CDDP plus GEM therapy was initiated. After the first 2 courses of therapy, the para-aortic lymph nodes markedly decreased in size, and the serum CA19-9 levels normalized. Grade 4 neutropenia and grade 3 thrombocytopenia were observed after 3 courses of therapy. We decreased the drug doses because toxicities were observed. We hesitated to discontinue therapy because the indications for discontinuing chemotherapy while the patient showed a good response were not known. Finally, we discontinued therapy after 28 courses because recovery from the resultant toxicities became difficult in spite of decreasing the drug doses(CDDP 25 mg/body, GEM 600 mg/body), and because a good response to therapy was confirmed by CT. The patient is alive and has been disease-free for more than 2 years.

Hepatocellular carcinoma development induced by conditional beta-catenin activation in Lkb1+/- mice.

The development of hepatocellular carcinomas (HCC) appears to be a multistep process that takes several decades in humans. However, the identities of specific gene alterations and their contribution to HCC pathogenesis remain poorly understood. We previously reported that Lkb1(+/-) mice spontaneously develop multiple hepatic nodular foci (NdFc) followed by HCC, and that the conditional activation of beta-catenin in Catnb(lox(ex3)) mouse livers alone does not cause tumor formation. We show here that the conditional activation of beta-catenin accelerates HCC development in Catnb(+/lox(ex3))Lkb1(+/-) compound mutant mice, affecting displastic hepatocytes in NdFc that suffered LOH at the Lkb1 locus. We further show that beta-catnin activation provides HCC with a growth advantage as well as transplantability. These results suggest that the loss of Lkb1 contributes to the formation of dysplastic NdFc, and that Wnt signaling activation is involved in ensuing progression toward HCC. A combination of these sequential changes can be a practical model for a subset of human HCC.

Thrombosis of the left brachiocephalic vein after subtotal esophagectomy with reconstruction using a retrosternally shifted gastric tube: Report of a case.

We performed a right transthoracic subtotal esophagectomy with systemic three-field lymph node dissection, followed by reconstruction with a gastric tube shifted retrosternally into the left side of the neck, for esophageal cancer in a 62-year-old woman. The patient had an uneventful postoperative course until postoperative day (POD) 9, when a venous thrombosis originating from the left brachiocephalic vein and elongating to the left subclavian vein was detected occasionally on computed tomography scans, although there were no clinical symptoms. The left brachiocephalic vein seemed narrowed by compression from the reconstructed gastric tube, and this was considered the cause of the thrombosis. The patient was commenced on thrombolytic therapy, using urokinase, and on anticoagulation therapy, using heparin and warfarin. The thrombus had disappeared completely by POD 38. The anticoagulation therapy was continued for 6 months and no recurrence of the thrombosis has been detected in the 4 months since its completion.

Hepatocellular carcinoma caused by loss of heterozygosity in Lkb1 gene knockout mice.

Germline mutations of the LKB1 gene are associated with Peutz-Jeghers syndrome, which is characterized by mucocutaneous pigmentation and gastrointestinal hamartoma with an increased risk of cancer development. To investigate the role of LKB1 in vivo, we have recently constructed Lkb1 gene knockout mice. Because of Lkb1 gene haploinsufficiency, the heterozygous Lkb1 mice develop gastrointestinal polyps of which the histological characteristics resemble those of the Peutz-Jeghers syndrome hamartomas. Here we demonstrate that the Lkb1 (+/-) mice develop hepatocellular carcinomas (HCCs). In Lkb1 (+/-) mice >50 weeks of age, >70% of the male mice developed HCCs, whereas only 20% of the females had HCCs, showing a sex difference in the susceptibility. Histological examinations revealed various types of HCCs, such as "trabecular," "clear cell," "pseudoglandular," and "sarcomatous" types, which were strikingly similar to those found in human HCCs. Western blotting and PCR analyses showed loss of Lkb1 heterozygosity in all of the HCC tissues examined, indicating a tumor suppressor role of LKB1 in the mouse liver. These results suggest that lack of LKB1 is a novel mechanism for HCC development. Thus, the Lkb1 (+/-) knockout mutant should be an important and useful model for human HCC.

Interleukin-12-gene transduction makes DCs from tumor-bearing mice an effective inducer of tumor-specific immunity in a peritoneal dissemination model.

Dendritic cells (DCs) from cancer patients, as well as tumor-infiltrating DCs, are reported to have suppressed immunostimulatory capacity. One of the major problems in the clinical use of DCs for treating tumors is that the DCs must be autologous ones obtained from patients. Compared with normal DCs (nDCs), flow-cytometric analysis and allogeneic mixed lymphocyte reaction (MLR) have revealed lower expression of the costimulatory molecules and suppressed T-cell-stimulatory activity in DCs derived from tumor-bearing mice (tDCs) despite of culture. We reported previously that the interleukin-12 (IL-12)-gene-transduced nDCs inhibited tumor growth due to induced tumor-specific Th1 and cytotoxic T cells (CTLs) in a murine established subcutaneous tumor model. In the present study, we examined whether tDCs could induce immune responses against tumors after IL-12-gene transduction in an established peritoneal dissemination model. The intraperitoneal injection of IL-12-gene-transduced tDCs resulted in prolonged survival of some treated mice (log-rank test; P=0.001) and tumor-specific Th1 and CTL activity. The injection of IL-12-gene-transduced nDCs prolonged the survival of all treated mice (P<0.0001) and elicited tumor-specific immunity, which were better than those of IL-12-gene-transduced tDCs. Taken together, DC modification of IL-12-gene transduction is an effective and promising approach for cancer therapy even when immunosuppressive tDCs are employed.

Gastrointestinal hamartomatous polyposis in Lkb1 heterozygous knockout mice.

Peutz-Jeghers syndrome (PJS) is a hereditary disorder characterized by gastrointestinal hamartomatous polyposis associated with mucocutaneous pigmentation. Germ-line mutations of the gene encoding LKB1 (STK11), a serine/threonine kinase, are identified in most PJS patients. To investigate the role of LKB1 in the PJS phenotypes, we introduced a germ-line mutation in the mouse Lkb1 gene by homologous recombination in mouse embryonic stem cells. In most Lkb1 (+/-) mice >20 weeks of age, hamartomatous polyps developed in the glandular stomach, often in the pyloric region. Small intestinal hamartomas also developed in approximately one-third of the Lkb1 (+/-) mice >50 weeks of age. A genomic PCR and sequence analysis showed that all hamartomas retained both the wild-type and targeted Lkb1 alleles, indicating that allelic loss of the wild-type Lkb1 was not the cause of polyp formation. Moreover, the LKB1 protein level was not reduced in hamartomatous polyps compared with that in the Lkb1 (+/-) normal gastric mucosa. In addition, the remaining allele showed neither missense mutations in the coding sequence nor produced truncated LKB1 in the hamartoma. Taken together, these data suggest that the wild-type Lkb1 is expressed in the hamartoma at the haploid amount. Accordingly, the gastrointestinal hamartomas appear to develop because of the Lkb1 haploinsufficiency. Although additional genetic events may be critical in hamartoma and adenocarcinoma development, these data strongly suggest that the initiation of polyposis is not the result of loss of heterozygosity in Lkb1.