Epstein-Barr virus-associated inflammatory pseudotumor variant of follicular dendritic cell sarcoma of the liver: a case report and review of the literature.

BACKGROUND: Follicular dendritic cell sarcoma is a rare stromal tumor with no standard treatment. However, some reports have revealed that follicular dendritic cell sarcoma has an inflammatory pseudotumor variant associated with Epstein-Barr virus infection that has a relatively good prognosis. In this report, we present a case of a resected inflammatory pseudotumor variant of follicular dendritic cell sarcoma of the liver, and have reviewed the literature on the clinicopathological, molecular, and genomic features of this tumor. CASE PRESENTATION: The inflammatory pseudotumor variant of follicular dendritic cell sarcoma originates only in the liver or spleen, causes no symptoms, and is more common in middle-aged Asian women. It has no characteristic imaging features, which partially explains why the inflammatory pseudotumor variant of follicular dendritic cell sarcoma is difficult to diagnose. Pathologically, the inflammatory pseudotumor variant of follicular dendritic cell sarcoma has spindle cells mixed with inflammatory cells and is variably positive for follicular dendritic cell markers (CD21, CD23, and CD35) and Epstein-Barr virus-encoded RNA. On genetic analysis, patients with this tumor high levels of latent membrane protein 1 gene expression and extremely low levels of host C-X-C Chemokine Receptor type 7 gene expression, indicating that the inflammatory pseudotumor variant of follicular dendritic cell sarcoma has a latent Epstein-Barr virus type 2 infection. CONCLUSIONS: The inflammatory pseudotumor variant of follicular dendritic cell sarcoma is an Epstein-Barr virus-associated tumor and a favorable prognosis by surgical resection, similar to Epstein-Barr virus-associated gastric cancer.

Phase II study of trifluridine/tipiracil plus bevacizumab by RAS mutation status in patients with metastatic colorectal cancer refractory to standard therapies: JFMC51-1702-C7.

BACKGROUND: Although the efficacy of trifluridine/tipiracil (FTD/TPI) plus bevacizumab (BEV) against metastatic colorectal cancer (mCRC) has been demonstrated, little is known about its effectiveness upon disease stratification by RAS mutations. In this phase II study, we investigated the efficacy and safety profiles of FTD/TPI in mCRC according to RAS mutation status. PATIENTS AND METHODS: Eligible patients were mCRC refractory or intolerant to all standard therapies other than FTD/TPI and regorafenib. Patients received 4-week cycles of treatment with FTD/TPI (35 mg/m2, twice daily, days 1-5 and 8-12) and bevacizumab (5 mg/kg, days 1 and 15). The primary endpoint was disease control rate (DCR). The null hypothesis of DCR in both RAS wild-type (WT) and mutant (MUT) cohorts was 44%, assuming a one-sided significance level of 5.0%. The necessary sample size was estimated to be 49 patients (target sample size: 50 patients) for each cohort. RESULTS: Between January and September 2018, 102 patients were enrolled, and 97 patients fulfilled the eligibility criteria (48 in the RAS WT cohort and 49 in the RAS MUT cohort). DCRs in the RAS WT and MUT cohort were 66.7% [90% confidence interval (CI), 53.9%-77.8%, P = 0.0013] and 55.1% (90% CI, 42.4%-67.3%, P = 0.0780), respectively. The median progression-free survival (PFS) and overall survival (OS) were 3.8 and 9.3 months, respectively, in the RAS WT cohort and 3.5 and 8.4 months, respectively, in the RAS MUT cohort. The most common grade 3 or higher adverse event in both cohorts was neutropenia (46% in the RAS WT cohort and 62% in the RAS MUT cohort), without unexpected safety signals. CONCLUSIONS: FTD/TPI plus bevacizumab showed promising activity with an acceptable safety profile for pretreated mCRC, regardless of RAS mutation status, although the efficacy outcomes tended to be better in RAS WT.

Prognostic significance of overexpression of c-Met oncoprotein in cholangiocarcinoma.

BACKGROUND: Cholangiocarcinoma (CC) is a highly malignant carcinoma. We attempted to clarify the prognostic significance of c-Met overexpression and its association with clinicopathological factors in patients with CC. PATIENTS AND METHODS: One hundred and eleven patients with intrahepatic CC (IHCC) and 136 patients with extrahepatic CC (EHCC) who had undergone curative surgery were divided immunohistologically into c-Met(high) and c-Met(low) groups. Clinicopathological factors and outcomes were compared between the groups. c-Met and epidermal growth factor receptor (EGFR) expression was also examined in 10 CC cell lines. RESULTS: The positivity of c-Met was 45.0% in IHCC and 68.4% in EHCC; c-Met(high) expression was demonstrated in 11.7% of IHCC and 16.2% of EHCC. c-Met(high) expression was significantly correlated with the 5-year survival rate for CC overall (P=0.0046) and for IHCC (P=0.0013), histopathological classification in EHCC, and for EGFR overexpression in both IHCC and EHCC. Coexpression and coactivation of c-Met and EGFR were also observed in CC cell lines. Multivariate analysis revealed that c-Met(high) expression was an independent predictor of poor overall and disease-free survival in patients with IHCC. CONCLUSIONS: c-Met overexpression is associated with EGFR expression and is a poor prognostic factor in CC.

Clinical impact of intraoperative histological examination of the ductal resection margin in extrahepatic cholangiocarcinoma.

BACKGROUND: Although ductal resection margin status in extrahepatic cholangiocarcinoma is evaluated by intraoperative histological examination of frozen sections, its clinical relevance remains controversial. METHODS: Material taken from patients who underwent R0 or R1 resection for extrahepatic cholangiocarcinoma with intraoperative histological examination of the final ductal resection margins between 1994 and 2003 were reviewed. The following histological classification was used: insufficient, negative for malignancy (NM), undetermined lesion (UDL) or positive for malignancy (PM). Multivariable analyses of overall survival and anastomotic recurrence in relation to ductal margin status were performed. RESULTS: Resection material from 363 patients was identified. For the proximal ductal margin, only PM in intramural lesions was significantly associated with poor survival (hazard ratio (HR) 1.72, 95 per cent confidence interval (c.i.) 1.06 to 2.74) and anastomotic recurrence (HR 6.39, 95 per cent c.i. 1.89 to 21.62) compared with NM. In analysis of overall survival according to distal ductal margin status, the HRs for UDL and PM lesions in comparison with NM were not significant. CONCLUSION: PM in intramural lesions found during intraoperative histological examination of the proximal ductal resection margin was related to clinical outcome. This finding favours additional resection of the bile duct. A similar association was not found for histology results of the distal resection margin.

Vandetanib (ZD6474), an inhibitor of VEGFR and EGFR signalling, as a novel molecular-targeted therapy against cholangiocarcinoma.

Cholangiocarcinoma is an intractable cancer, with no effective therapy other than surgical resection. Elevated vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR) expressions are associated with the progression of cholangiocarcinoma. We therefore examined whether inhibition of VEGFR and EGFR could be a potential therapeutic target for cholangiocarcinoma. Vandetanib (ZD6474, ZACTIMA), a VEGFR-2/EGFR inhibitor, was evaluated. Four human cholangiocarcinoma cell lines were molecularly characterised and investigated for their response to vandetanib. In vitro, two cell lines (OZ and HuCCT1), both of which harboured KRAS mutation, were refractory to vandetanib, one cell line (TGBC24TKB) was somewhat resistant, and another cell line (TKKK) was sensitive. The most sensitive cell line (TKKK) had EGFR amplification. Vandetanib significantly inhibited the growth of TKKK xenografts at doses > or = 12.5 mg kg(-1) day(-1) (P<0.05), but higher doses (50 mg kg(-1) day(-1), P<0.05) of vandetanib were required to inhibit the growth of OZ xenografts. Vandetanib (25 mg kg(-1) day(-1)) also significantly (P=0.006) prolonged the time to metastasis in an intravenous model of TKKK metastasis. Inhibiting both VEGFR and EGFR signalling appears a promising therapeutic approach for cholangiocarcinoma. The absence of KRAS mutation and the presence of EGFR amplification may be potential predictive molecular marker of sensitivity to EGFR-targeted therapy in cholangiocarcinoma.

Clinicopathological and prognostic significance of EGFR, VEGF, and HER2 expression in cholangiocarcinoma.

Epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF), and human epidermal growth factor receptor 2 (HER2) have been considered as potential therapeutic targets in cholangiocarcinoma, but no studies have yet clarified the clinicopathological or prognostic significance of these molecules. Immunohistochemical expression of these molecules was assessed retrospectively in 236 cases of cholangiocarcinoma, as well as associations between the expression of these molecules and clinicopathological factors or clinical outcome. The proportions of positive cases for EGFR, VEGF, and HER2 overexpression were 27.4, 53.8, and 0.9% in intrahepatic cholangiocarcinoma (IHCC), and 19.2, 59.2, and 8.5% in extrahepatic cholangiocarcinoma (EHCC), respectively. Clinicopathologically, EGFR overexpression was associated with macroscopic type (P=0.0120), lymph node metastasis (P=0.0006), tumour stage (P=0.0424), lymphatic vessel invasion (P=0.0371), and perineural invasion (P=0.0459) in EHCC, and VEGF overexpression with intrahepatic metastasis (P=0.0224) in IHCC. Multivariate analysis showed that EGFR expression was a significant prognostic factor (hazard ratio (HR), 2.67; 95% confidence interval (CI), 1.52-4.69; P=0.0006) and also a risk factor for tumour recurrence (HR, 1.89; 95% CI, 1.05-3.39, P=0.0335) in IHCC. These results suggest that EGFR expression is associated with tumour progression and VEGF expression may be involved in haematogenic metastasis in cholangiocarcinoma.

Phase I/II study of S-1 combined with paclitaxel in patients with unresectable and/or recurrent advanced gastric cancer.

Both paclitaxel and S-1 are effective against gastric cancer, but the optimal regimen for combined chemotherapy with these drugs remains unclear. This phase I/II study was designed to determine the maximum tolerated dose (MTD), recommended dose (RD), dose-limiting toxicity (DLT), and objective response rate of paclitaxel in combination with S-1. S-1 was administered orally at a fixed dose of 80 mg m-2 day-1 from days 1 to 14 of a 28-day cycle. Paclitaxel was given intravenously on days 1, 8, and 15, starting with a dose of 40 mg m-2 day-1. The dose was increased in a stepwise manner to 70 mg m-2. Treatment was repeated every 4 weeks unless disease progression was confirmed. In the phase I portion, 17 patients were enrolled. The MTD of paclitaxel was estimated to be 70 mg m-2 because 40% of the patients given this dose level (two of five) had DLT. The RD was determined to be 60 mg m-2. In the phase II portion, 24 patients, including five with assessable disease who received the RD in the phase I portion, were evaluated. The median number of treatment courses was six (range: 1-17). The incidence of the worst-grade toxicity in patients given the RD was 28 and 8%, respectively. All toxic effects were manageable. The response rate was 54.1%, and the median survival time was 15.5 months. Our phase I/II trial showed that S-1 combined with paclitaxel is effective and well tolerated in patients with advanced gastric cancer.

Microtopography of the dual corticothalamic projections originating from domains along the frequency axis of the cat primary auditory cortex.

Spatial relationships between clusters of corticothalamic (CT) large terminals originating from cortical domains tuned to different frequencies were examined by pair-injecting two different anterograde tracers. Large-terminal CT projection originating from layer 5 was highly divergent with each injection site producing, on average, 15 local clusters distributing throughout non-lemniscal thalamic nuclei following a single anterograde tracer injection in the cat primary auditory cortex. Paired injections in higher- and lower-frequency cortical domains, resulting in labeling of two independent sets of terminal clusters, showed five recognizable patterns of spatial interaction between them. (1) In the ventral division of the medial geniculate complex (vMGC), sheet-like plexuses of small terminals of different origins were situated in parallel, with minimal overlap. (2) Extensive overlap of two low-density plexuses of differently labeled small terminals was observed in the medial division of the medial geniculate complex (MGC). (3) At the transition zones between the vMGC and the superficial dorsal nucleus of the MGC dorsal division, and between the vMGC and the ventrolateral nucleus, there were relatively broad clusters of a high density of large-terminal structures from the two cortical domains, which overlapped extensively. (4) At multiple loci in the nonlemniscal nuclei, pairing of two small clusters of differently labeled large terminals was observed. (5) Small unpaired clusters of large terminals were also found in the nonlemniscal nuclei. For large terminals, approximately 14%, 59%, and 27% clusters per injection demonstrated patterns 3, 4, and 5, respectively. The results provide evidence for the precise topographical organization for the large-terminal CT system at the microscopic level despite its highly divergent projection. This microtopographical projection from the tonotopic cortical field to non-tonotopic thalamic nuclei may raise the possibility of presence of a map that has not been defined in auditory non-lemniscal thalamic nuclei yet.

Spontaneous regression of hepatocellular carcinoma with complete necrosis: case report.

Spontaneous regression of hepatocellular carcinoma is rare phenomenon. A 74-year-old man was found to have a hepatocellular carcinoma with intrahepatic metastases in the lateral segment of the liver. Before surgery, he developed severe cholangitis due to choledocholithiasis and was treated endoscopically. The tumor marker level decreased markedly, and hepatectomy was performed. The resected tumor demonstrated complete necrosis.