Gadoxetic acid disodium-enhanced MR imaging of cholangiolocellular carcinoma of the liver: imaging characteristics and histopathological correlations.

OBJECTIVES: To review the gadoxetic acid disodium (EOB)-enhanced magnetic resonance (MR) imaging features of cholangiolocellular carcinoma (CoCC) of the liver and compare them with those of hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). METHODS: EOB-enhanced MR images of 19 patients with CoCC, 23 with ICC, and 51 with HCC were retrospectively evaluated qualitatively and quantitatively. Univariate and multivariate analyses were performed to determine the characteristic MR features of CoCC with histopathological-imaging correlation. RESULTS: Multivariate logistic regression analysis showed that dot-/band-shaped internal enhancement during the arterial and portal phases (P < 0.001), and larger arterial ring enhancement ratio (CoCC, 0.13 ± 0.04; ICC, 0.074 ± 0.04; P = 0.013) were significantly independently associated with CoCC in contrast to ICC, whereas several MR features including progressive enhancement during the portal and late phases (P < 0.001), target appearance in the hepatocyte phase (P = 0.004), and vessel penetration (P = 0.013) were significantly more frequently associated with CoCC than HCC. The dot-/band-like internal enhancement (78.9% of CoCCs) histopathologically corresponded to the tumour cell nest with vascular proliferations and retained Glisson's sheath structure. CONCLUSIONS: EOB-enhanced MR features of CoCC largely differ from those of HCC but are similar to those of ICC. However, the finding of thicker arterial ring enhancement with dot-/band-like internal enhancement could help differentiate CoCC from ICC. KEY POINTS: • Gadoxetic acid-enhanced MR features of cholangiolocellular carcinoma (CoCC) resembled those of intrahepatic cholangiocarcinoma (ICC). • Gadoxetic acid-enhanced MR features of CoCC largely differed from those of hepatocellular carcinoma. • Dot-/band-like internal enhancement of CoCC may be helpful for differentiating from ICC. • Arterial ring enhancement of CoCC was larger than that of ICC.

Indications for Lateral Pelvic Lymph Node Dissection Based on Magnetic Resonance Imaging Before and After Preoperative Chemoradiotherapy in Patients with Advanced Low-Rectal Cancer.

BACKGROUND: We assessed the magnetic resonance imaging (MRI) findings of lateral pelvic lymph node (LPLN) metastasis in patients with advanced low-rectal cancer treated with preoperative chemoradiotherapy (CRT) and LPLN dissection (LPLD) for clinically suspected LPLN metastasis. Our aim was to identify the optimal indications for LPLD. METHODS: The study population consisted of 77 patients with advanced low-rectal cancer who underwent LPLD for clinically suspicious LPLN metastasis after preoperative CRT. MRI findings before/after CRT, clinical factors, and LPLN metastasis were evaluated. RESULTS: LPLN metastasis was confirmed in 31 patients (40.3 %). Metastasis was significantly higher in patients with LPLNs with a short-axis diameter ≥8 mm than in patients with LPLNs with a short-axis diameter <8 mm before CRT (75 vs. 20 %, P < 0.0001). LPLN metastasis was also significantly higher in patients with LPLNs with a short-axis diameter >5 mm than in patients with LPLNs with a short-axis diameter ≤5 mm after CRT (75 vs. 20 %, P < 0.0001). Multivariate analysis showed the independent association of female sex [P = 0.0192; odds ratio (OR) 5.616; 95 % confidence interval (CI) 1.315-28.942], pre-CRT short-axis diameter of the LPLN ≥8 mm (P = 0.0047; OR 9.188; 95 % CI 1.948-54.366), and CRT without induction systemic chemotherapy (P = 0.0285; OR 9.235; 95 % CI 1.241-106.947) with LPLN metastasis. CONCLUSIONS: MRI before CRT is useful to predict LPLN metastasis and to determine the indications for LPLD.

Selective lateral pelvic lymph node dissection in patients with advanced low rectal cancer treated with preoperative chemoradiotherapy based on pretreatment imaging.

BACKGROUND: The significance of lateral pelvic lymph node (LPLN) metastasis in advanced low rectal cancer treated with preoperative chemoradiotherapy (CRT) remains unclear. The objective of this study was to evaluate the outcomes of selective LPLN dissection (LPLD) based on the pretreatment imaging in patients with advanced low rectal cancer treated with preoperative CRT. METHODS: We reviewed 127 consecutive patients with clinical stage II-III low rectal cancer below the peritoneal reflection who underwent preoperative CRT and curative resection. LPLD was performed in patients with suspected LPLN metastasis based on MDCT or MRI before CRT (LPLD group, N = 38), and only total mesorectal excision (TME) was performed in patients without suspected LPLN metastasis (TME group, N = 89). Clinical characteristics and the oncological outcome were compared between groups. RESULTS: The median tumor-to-anal verge distance was 40 mm in both groups. The median maximum long-axis LPLN diameter before CRT was 0 mm in the TME group and 10.5 mm in the LPLD group. Pathological LPLN metastasis was confirmed in 25 patients (66 %) in the LPLD group. Local recurrence at LPLN developed in 3 patients (3.4 %) in the TME group and in none (0 %) of the LPLD group. Multivariate analysis showed that only ypN was an independent prognostic factor for relapse-free survival (RFS), but LPLN metastasis was not associated with poor RFS. CONCLUSIONS: The incidence of LPLN metastasis is high even after preoperative CRT, and LPLD might improve local control and survival of patients with LPLN metastasis in advanced low rectal cancer treated with preoperative CRT.

Embolization of Vessels With Irregular Lumen Using the Coil Packing Technique Between the Amplatzer Vascular Plug II Lobes.

INTRODUCTION: The Amplatzer Vascular Plug (AVP) series enables precise positioning and high migration resistance, allowing embolization in short segments; however, inadequate embolization or recanalization may occasionally occur. We hypothesized that leaks may occur when AVPs are implanted in vessels with irregular lumen due to insufficient adherence to the vessel. This hypothesis was tested by experiments with a vascular model. We employed a coil packing technique between the AVP lobes to embolize internal iliac arteries with an irregular lumen. METHODS: Saline was injected through the Y-shaped glass tubes of the stenotic and the smooth model (without stenotic lesion), and the amount of leakage was measured when the AVP was deployed. The feasibility and effectiveness of filling coils between the lobes of AVP II were evaluated. A total of 11 cases were retrospectively reviewed using this technique for internal iliac artery embolization prior to endovascular aortic repair. RESULTS: The amount of leakage was significantly higher in the presence of stenotic lesions. Insertion of a 2.2 F microcatheter from the side of the proximal lobe of AVP II and filling of coils was achieved in all 11 cases. Follow-up contrast-enhanced CT showed no recanalization, leakage, or other obvious complications. CONCLUSION: Coil packing technique around Amplatzer Vascular Plugs could be an effective method and a reliable option for arterial embolization, especially in vessels with irregular lumens.

Case Report: Spontaneous Postpartum Quadruple Cervicocephalic Arterial Dissection With a Heterozygous COL5A1 Variant of Unknown Significance.

Pregnancy-associated cervicocephalic arterial dissection is rare, and its pathophysiology remains poorly understood. Despite the hypothesized contribution to pathogenesis, connective tissue diseases and genetic factors are rarely identified in clinical cases. We describe a case of postpartum arterial dissection involving all four cervicocephalic arteries resulting in acute cerebral infarction. The patient underwent successful endovascular thrombectomy and angioplasty and recovered fully without sequelae. Genetic screening for connective tissue diseases identified a heterozygous missense COL5A1 variant with unknown clinical significance. Two genetically related family members later developed arterial abnormalities, and one of them tested positive for the same COL5A1 gene variant as our patient, while the other was scheduled for genetic testing. The extensive clinical presentation of our patient and the prevalence of arterial abnormalities in her family warrant further assessment of the association between the identified COL5A1 gene variant and the pathogenesis of arterial dissections.

A Case Report of an Intrathoracic Mass Lesion Caused by Arcanobacterium haemolyticum that Required Exclusion of a Malignant Tumor Diagnosis.

A 57-year-old man with untreated diabetes mellitus was admitted to our hospital due to an intrathoracic mass lesion infiltrating the vertebral body and mediastinum. The mass was suspected to be invasive lung cancer; however, percutaneous needle biopsy revealed that the mass was inflammatory granulation tissue caused by an Arcanobacterium haemolyticum infection. To the best of our knowledge, this is the first report of an intrathoracic mass lesion caused by an A. haemolyticum infection. When an intrathoracic mass lesion is suspected, clinicians should consider possible infections that cause granulation tissue, such as A. haemolyticum. This is particularly important in immunocompromized hosts such as patients with diabetes.

Impact of portal vein resection with splenic vein reconstruction after pancreatoduodenectomy on sinistral portal hypertension: Who needs reconstruction?

BACKGROUND: Resection of the porto-mesenterico-splenic confluence is at times necessary during pancreatoduodenectomy with portal vein resection for pancreatic cancer. Although splenic vein ligation can cause sinistral portal hypertension, the incidence of clinically relevant sinistral portal hypertension remains unknown, and the roles of the preservation of potential collateral veins and splenic vein reconstruction are controversial. METHODS: Patients with pancreatic cancer who underwent pancreatoduodenectomy with porto-mesenterico-splenic confluence resection were assessed for incidence of development of varices by computed tomography at 6 months after pancreatoduodenectomy. We evaluated the risk factors for sinistral portal hypertension and the impact of splenic vein reconstruction on sinistral portal hypertension. RESULTS: Of the 118 patients who underwent pancreatoduodenectomy with porto-mesenterico-splenic confluence resection, 31 (26%) underwent splenic vein reconstruction, 44 patients (37%) developed gastroesophageal varices, and 5 (11%) experienced varix rupture. Sacrifice of all 3 potential collateral veins (what we refer to as the critical veins: left gastric vein, middle colic vein, and superior right colic vein arcade) and absence of any spontaneous splenorenal shunt had a substantial impact on formation of varices. The risk of variceal formation could be stratified based on the number of preserved critical veins, and patent splenic vein reconstruction was associated with a decreased incidence of varices (60% versus 100%, P = .018) among the patients without preservation of the critical veins. In contrast, patients with multiple intact critical veins developed no varices, regardless of splenic vein reconstruction. CONCLUSIONS: Sinistral portal hypertension is not uncommon after pancreatoduodenectomy with porto-mesenterico-splenic confluence resection, and the number of preserved critical veins helps to predict the risk of sinistral portal hypertension. Thus, the indication for splenic vein reconstruction should be tailored according to individual risk factors.

A case of inflammatory hepatocellular adenoma displaying an unusual histological pattern.

Hepatocellular adenoma (HCA) is a rare type of liver tumor. Here, we report a variant case of HCA in a 56-year-old Japanese man which displayed unusual histological features. The patient had undergone surgery for esophageal and gastric cancer 2 years prior. A computed tomography scan performed in the follow-up period detected a single lesion (diameter 1.4 cm) in the right posterior lobe of the liver, leading to a partial hepatectomy. Histologically, the lesion was composed of two different types of cells. The larger cells, which accounted for most of the cells in the tumor, exhibited granular and eosinophilic cytoplasm, large nuclei and apparent nucleoli. These cells, which were designated the common cells, were typical of the HCA. The other cells, which were designated the pyknotic cells, were smaller, possessed an eosinophilic, homogeneous cytoplasm and pyknotic small nuclei, but did not contain nucleoli. Immunohistochemically, the common cells reacted strongly positive for C-reactive protein and serum amyloid A, which is compatible with a diagnosis of inflammatory HCA; in contrast, the pyknotic cells tested negative for these molecules. Since the pyknotic cells tested positive for several markers of apoptosis, they were considered to be apoptotic. In addition, as the common cells demonstrated a higher ki-67 labeling index, the lesion was considered to display upregulated cell kinetics, i.e. increases in both cell growth and death. Although HCA is a rare type of tumor, there have been several reports on HCA variants. The case reported here is that of a new type of HCA variant that demonstrated an unusual histological pattern and upregulated cell kinetics.