[Evaluation of the Therapeutic Effect of Using Dual-Energy CT for Rectal Cancer after Neoadjuvant Chemotherapy]

It is difficult to know the effects of preoperative treatment on advanced rectal cancer even if using a variety of diagnostic imaging modalities. We report the efficacy of evaluating the therapeutic effect of using dual-energy CT(DECT)against rectal cancer after neoadjuvant chemotherapy(NAC). The subject sample consisted of1 1 patients who underwent rectal cancer surgery after NAC from September 2015 to January 2016. The pathological effective grade was higher if the after/before ratio ofcontrast enhancement on DECT was small(Grade 1a: 1.4, Grade 1b: 0.8, Grade 2: 0.4, Grade 3: 0.3). Therefore, a successful response rate occurred if blood flow was reduced after NAC. In this study, it was possible to predict the pathological response grade for rectal cancer via contrast enhancement using DECT.

[Laparoscopic Lateral Lymph Node Dissection for Rectal Cancer with Lateral Lymph Node Metastasis - A Case Report]

BACKGROUND

Lateral lymph node dissection(LLND)for locally advanced lower rectal cancer is the standard treatment procedure in Japan. We performed LLND with an extraperitoneal approach. Recently, we introduced laparoscopic surgery for locally advanced rectal cancer and laparoscopic LLND. We performed laparoscopic LLND in a patient havinglower rectal cancer with lateral lymph node metastasis that was detected via preoperative imaging.

CASE PRESENTATION

The patient was a woman in her 50s who experienced melena and visited a physician. Colonoscopy revealed a tumor in the lower rectum and computed tomography showed lateral lymph node swelling and liver metastasis. The patient was referred to our institution and she was diagnosed with lower rectal cancer having lateral lymph node and synchronous liver metastases. We performed laparoscopic abdominoperineal resection and laparoscopic LLND. The operatingtime was 260 min, and the blood loss was 60g.

CONCLUSION

The magnification of laparoscopy enables precision in the surgical operation of the narrow pelvis during lymph node dissection, allowingautonomic nerve preservation. Therefore, laparoscopic LLND is a helpful procedure in the treatment of locally advanced rectal cancer with a lateral lymph node metastasis.

[A Case of Pathological Complete Response after Neoadjuvant Chemotherapy(S-1 plus Oxaliplatin)and Laparoscopic Low Anterior Resection for Rectal Cancer]

We report a case of pathological complete response after neoadjuvant chemotherapy(NAC)(S-1 plus oxaliplatin)for rectal cancer. The patient was a 50-year-old man who had type 3 circumferential rectal cancer. An abdominal CT scan revealed locally advanced rectal cancer(cT3N2H0P0M0, cStage III b)with severe stenosis and oral-side intestinal dilatation. The patient was treated with NAC after loop-ileostomy. After 3 courses of chemotherapy, a CT scan revealed significant tumor reduction. Laparoscopic low anterior resection and bilateral lymph node dissection were performed 5 weeks after the last course of chemotherapy. The pathological diagnosis was a pathological complete response(no residual cancer cells). This case suggests that laparoscopic low anterior resection after NAC with S-1 plus oxaliplatin for locally advanced rectal cancer is a potentially effective procedure.

[Assessment of Functional Results after Sphincter-Preserving Surgery in Elderly Patients with Low Rectal Cancer]

The aim of this study was to evaluate postoperative dysfunction and potential problems after a sphincter-preserving operation in elderly patients with low rectal cancer.

METHODS

Between 2000 and 2012, 307 consecutive patients with low rectal cancer underwent curative sphincter-preserving surgery. We evaluated postoperative anal and urinary dysfunction in 190 patients who responded to a questionnaire by mail.

RESULTS

After a median follow-up of 5.7 years, there was no significant difference between the elderly and a younger group in the Wexner incontinence score. Poor anal function assessed by modified FIQL was significantly associated with the elderly. Poor urinary function assessed by the IPSS score was significantly associated with the elderly, diabetes mellitus, and autonomic nerve preservation(AN2-3).

CONCLUSION

From the viewpoint of urinary function, sphincter-preserving surgery with all autonomicnerve preservation(AN4)should be considered for elderly people and patients with diabetes.

[A Case of Laparoscopic Surgery for Rectal Cancer with Synchronous Lung Metastases after Chemotherapy]

A woman in her 70's presented with the predominant complaint of bloody stools. She was diagnosed with rectal cancer, and bilateral lymph node and pulmonary metastases were detected on computed tomography(CT). The patient was diagnosed with cT3N3M1a, cStage IV disease. After undergoing a colostomy, the patient was treated with S-1 plus oxaliplatin (SOX), and bevacizumab(Bev). A second CT scan obtained after completion of 7 courses of chemotherapy revealed that the lung metastases had significantly reduced or disappeared. Approximately 7 months after initial treatment, the patient underwent a laparoscopic Hartmann procedure to remove the tumor. The patient is currently under observation while being administered postoperative adjuvant chemotherapy as an outpatient in our department. There is currently no evidence of the safety of laparoscopic-assisted rectal cancer surgery for first-time Stage IV cases. However, when tumor regression has been achieved with chemotherapy, it may be an effective option.

Randomized clinical trial comparing two vessel-sealing devices with crush clamping during liver transection

Background

Previous RCTs have failed to demonstrate the usefulness of combining energy devices with the conventional clamp crushing method to reduce blood loss during liver transection. Here, the combination of an ultrasonically activated device (UAD) and a bipolar vessel-sealing device (BVSD) with crush clamping was investigated.

Methods

Patients scheduled to undergo hepatectomy at the University of Tokyo Hospital or Nihon University Itabashi Hospital were eligible for this parallel-group, single-blinded randomized study. Patients were assigned to a control group (no energy device used), an UAD group or a BVSD group. The primary endpoint was the volume of blood loss during liver transection. Outcomes of the control group and the combined energy device groups (UAD plus BVSD) were first compared. Pairwise comparisons among the three groups were made for outcomes for which the combined energy device group was superior to the control group.

Results

A total of 380 patients were enrolled between July 2012 and May 2014; 116 patients in the control group, 122 in the UAD group and 123 in the BVSD group were included in the final analysis. Median blood loss during liver transection was lower in the combined energy device group (245 patients) than in the control group (116 patients): median 190 (range 0–3575) versus 230 (range 3–1570) ml (P = 0·048). Pairwise comparison revealed that blood loss was lower in the BVSD group than in the control group (P = 0·043).

Conclusion

The use of energy devices combined with crush clamping reduced blood loss during liver transection. Registration number: C000008372 (www.umin.ac.jp/ctr/index.htm).

Skull Metastasis from Hepatocellular Carcinoma

CT, MR and angiographic findings of 6 patients with 9 skull metastases from hepatocellular carcinoma (HCC) were reviewed. In 3 of 6 patients, local pain or neurologic deficit was the initial main manifestation of the disease, although all had been treated for chronic liver disease. In the remaining 3 patients, skull metastases were detected following treatment of HCC. The metastatic lesions appeared as expansile osteolytic masses on CT and as hypervascular masses on angiography. All lesions were demonstrated on MR imaging. Compared with the brain parenchyma, the lesions were iso- or hypointense on T1-weighted and T2-weighted MR images. The lesions were moderately to markedly enhanced by Gd-DTPA. Flow voids were shown in the tumors in 5 lesions. HCC should be included in the differential diagnosis of an osteolytic hypervascular lesion of the skull, especially in Oriental patients. The relatively hypointense tumor on T2-weighted MR images associated with flow void, different from primary skull tumors or directly invasive tumors, may support the diagnosis of HCC metastasis.

Atlantoaxial Subluxation

Twenty-nine patients with atlantoaxial subluxation (18 with rheumatoid arthritis, 2 due to trauma, 4 with os odontoideum, and one each with polyarteritis nodosa, rheumatic fever, Klippel-Feil syndrome, achondroplasia, and cause unknown) were evaluated using a 0.22 tesla resistive MRI unit. Cord compression was classified into four grades according to the degree on magnetic resonance imaging. There were 7 patients with no thecal sac compression (grade 0), 10 with a minimal degree of subarachnoid space compression without cord compression (grade 1), 7 with mild cord compression (grade 2), and 5 with severe cord compression or cord atrophy (grade 3). Although the severity of myelopathy showed poor correlation with the atlantodental interval on conventional radiography, high correlation was observed between MR grading and the degree of myelopathy. The high signal intensity foci were observed in 7 of 12 patients with cord compression (grades 2 and 3) on T2 weighted images. Other frequently observed findings in rheumatoid arthritis included soft tissue masses of low to intermediate signal intensity in the paraodontoid space, erosions of the odontoid processes, and atlantoaxial impaction on T1 and T2 weighted images.

Prognostic and clinical impact of sarcopenia in esophageal squamous cell carcinoma

Recently, depletion of skeletal muscle mass (sarcopenia) has been linked to poor prognosis in several types of cancers, but has not been investigated in esophageal squamous cell carcinoma (ESCC). This retrospective study investigates the relationship between sarcopenia and clinical outcome in ESCC patients treated by surgical resection or definitive chemoradiation therapy (dCRT). The study was retrospectively conducted in a single academic hospital in Kumamoto, Japan, and involved 325 ESCC patients (256 surgical cases and 69 dCRT cases) treated between April 2005 and April 2011. Skeletal muscle mass was quantified by radiologic measures using standard computed tomography scans. The skeletal muscle tissue in the 325 ESCC patients was distributed as follows: mean: 47.10; median: 46.88; standard deviation (SD): 7.39; range: 31.48-71.11; interquartile range, 46.29-47.90. Skeletal muscle tissue was greater in male patients than in female patients (P < 0.0001), but was independent of other clinical and tumor features. Sarcopenia was not significantly associated with overall survival (log rank P = 0.54). Lymph node involvement significantly altered the relationship between sarcopenia and survival rate (P for interaction = 0.026). Sarcopenia significantly reduced the overall survival of patients without lymph node involvement (log rank P = 0.035), but was uncorrelated with overall survival in patients with lymph involvement (log rank, P = 0.31). The anastomosis leakage rate was significantly higher in the sarcopenia group than in the non-sarcopenia group (P = 0.032), but other surgical complications did not significantly differ between the two groups. Sarcopenia in ESCC patients without lymph node involvement is associated with poor prognosis, indicating sarcopenia as a potential biomarker for identifying patients likely to experience an inferior outcome. Moreover, sarcopenia was associated with anastomosis leakage but no other short-term surgical outcome.

Vaspin prevents elevation of blood pressure through inhibition of peripheral vascular remodelling in spontaneously hypertensive rats

AIM

Visceral adipose tissue-derived serine protease inhibitor (vaspin) is a relatively novel adipocytokine with protective effects on metabolic diseases including obesity and type II diabetes. We have previously demonstrated that vaspin exerts anti-inflammatory and antimigratory roles through antioxidative effects in vascular smooth muscle cells. As inflammatory responses and migration of smooth muscle in peripheral vascular wall are key mechanisms for the pathogenesis of hypertension, we hypothesized that vaspin could prevent the development of hypertension in in vivo hypertensive animal model.

METHODS

Vaspin (1 μg kg(-1)  day(-1) ) was administered intraperitoneally to 5-week-old male spontaneously hypertensive rats (SHR) for 4 weeks. Superior mesenteric artery was isolated and used for measurement of isometric contraction and histological analysis.

RESULTS

Long-term vaspin treatment significantly prevented an elevation of systolic blood pressure (SBP) at 8 weeks of age. Vaspin had no effect on reactivity of isolated mesenteric artery from SHR. In contrast, vaspin significantly inhibited mesenteric arterial wall hypertrophy in SHR. Moreover, vaspin significantly inhibited an increase of tumour necrosis factor-α expression and a production of reactive oxygen species in isolated mesenteric artery from SHR.

CONCLUSION

This study for the first time demonstrates that vaspin prevents the increase of SBP in SHR through inhibiting peripheral vascular hypertrophy possibly via antioxidative and anti-inflammatory mechanisms.

Predictors of obstructive sleep apnoea-hypopnea severity and oral appliance therapy efficacy by using lateral cephalometric analysis

Obstructive sleep apnoea-hypopnea (OSAH) is a common disorder characterised by repetitive complete or partial closure of the upper airway during sleep, which results in sleep fragmentation and oxygen desaturation. There is growing interest in the use of oral appliances (OAs) to treat OSAH. The purpose of this study was to clarify the cephalometric factors that are associated with OSAH severity and that predict the outcome of OA therapy. Two hundred nine patients with OSAH were recruited and analysed retrospectively. They had a polysomnographically documented apnoea-hypopnea index (AHI) of more than five respiratory events per hour. Lateral skull radiographs were used for cephalometric analysis. Only 67 of the 209 recruited patients underwent a second polysomnography (PSG) to evaluate the efficacy of OA therapy. In all recruited patients, the angle formed by the subspinal point (A) to the nasion (N) to the supramental point (B) (i.e. ANB angle) and the distance between the mandibular plane and hyoid bone (MP-H) were predictive factors of OSAH severity. In only 67 patients underwent PSG with an OA, the mean rate of decrease in the AHI was 47·8 ± 29·1%. OA therapy effectively treated OSAH in some patients with a very severe form of OSAH. However, patients who had a high position of the hyoid bone had a poor response to OA therapy. This study suggested that cephalometric analysis is useful for predicting OSAH severity and OA therapy efficacy.

Use of a Right Lateral Sector Graft in Living Donor Liver Transplantation Is Feasible, but Special Caution Is Needed With Respect to Liver Anatomy

Right lateral sector (RLS) grafting has been introduced to enlarge the potential donor pool for living donor liver transplantation (LDLT); however, evidence of its feasibility is limited. Data from 437 LDLTs carried out between 2000 and 2013 were analyzed retrospectively. LDLTs using a right liver graft (n = 251) were compared with those using a RLS graft (RLSG; n = 28). No donor mortality occurred, and the major complication rates were similar between the two groups. Postoperative liver function preservation was better in the RLSG donors. Concerning the recipients, the mortality and overall survival rates were similar between the two groups. The complication rate for the recipients was higher when more than two arterial or biliary anastomoses were necessary. A systematic literature search identified four reports on LDLT using RLSGs. Among 66 LDLTs, including the present series, there were no cases of donor death, and the rates of major and minor complications in the donors were 6% and 29%, respectively. The major complication and overall mortality rates in the recipients were 29% and 6%, respectively. LDLT using an RLSG is feasible, with an acceptable survival rate among the recipients.

Development of a compact ECR ion source for various ion production

There is a desire that a carbon-ion radiotherapy facility will produce various ion species for fundamental research. Although the present Kei2-type ion sources are dedicated for the carbon-ion production, a future ion source is expected that could provide: (1) carbon-ion production for medical use, (2) various ions with a charge-to-mass ratio of 1/3 for the existing Linac injector, and (3) low cost for modification. A prototype compact electron cyclotron resonance (ECR) ion source, named Kei3, based on the Kei series has been developed to correspond to the Kei2 type and to produce these various ions at the National Institute of Radiological Sciences (NIRS). The Kei3 has an outer diameter of 280 mm and a length of 1120 mm. The magnetic field is formed by the same permanent magnet as Kei2. The movable extraction electrode has been installed in order to optimize the beam extraction with various current densities. The gas-injection side of the vacuum chamber has enough space for an oven system. We measured dependence of microwave frequency, extraction voltage, and puller position. Charge state distributions of helium, carbon, nitrogen, oxygen, and neon were also measured.

Clinicopathological significance of vascular endothelial growth factor, thymidine phosphorylase and microvessel density in colorectal cancer

Colorectal cancer is a common malignant disease, the incidence of which is increasing worldwide, therefore, identifying novel prognostic factors to improve adjuvant therapeutic strategies or postoperative monitoring is required. Angiogenesis, which is assessed by microvessel density (MVD), is significant in tumor growth and metastasis. However, the association between angiogenesis and clinical outcome remains controversial. In the present study, 84 surgically resected cases of colorectal cancer were examined to clarify the clinicopathological significance of vascular endothelial growth factor (VEGF), thymidine phosphorylase (TP) and cluster of differentiation (CD)34 expression levels. VEGF expression was identified to be significantly correlated with TP expression (r=0.45; P<0.0001) and MVD in the high VEGF expression group was observed to be significantly greater than that in the low VEGF expression group (P=0.0194). In the Dukes' stage D group, the MVD in the high TP expression group was significantly greater than that in the low TP expression group (P=0.0149). High VEGF expression was subsequently correlated with a short overall survival rate for patients exhibiting lymph node metastasis (P=0.0128); however, there was no significant difference in overall survival rate regarding the expression levels of TP and CD34. The results of the present study indicate that VEGF expression may serve as a prognostic factor for colorectal cancer patients exhibiting lymph node metastasis. Furthermore, angiogenesis, as assessed by MVD, is an important prognostic factor for tumor growth at the primary site.

[Treatment Strategy for Stage Ⅳ Rectal Cancer]

Eighteen consecutive patients who underwent rectal resection following preoperative chemotherapy for cStage Ⅳ rectal cancer at our institute, between 2009 and 2014, were retrospectively assessed. Preoperative chemotherapy with mFOLFOX6, SOX, XELOX, and other anticancer agents was administered to 8, 5, 3, and 2 patients, respectively. Combined molecular targeted therapy was administered to 12 patients. The response evaluation showed that an antitumor effect was observed in 10 and 8 patients with local tumors who achieved a partial response (PR) and stable disease (SD), respectively, and in 9 and 9 patients with distant metastases who achieved a PR and SD, respectively. The operative procedures included high/low anterior resection (n=12), intersphincteric resection (n=2), and abdominoperineal resection/Hartmann's operation (n=4). An ileostomy was performed in 6 patients before chemotherapy. Postoperative complications occurred in 6 patients. Two patients with an ileostomy had anastomotic insufficiency, but recovered without reoperation. There was no significant difference in overall survival (p=0.382) when these patients were compared with 45 cStage Ⅳ rectal cancer patients who underwent surgery without preoperative chemotherapy. However, the rate of curability B was higher in patients who received preoperative chemotherapy (44.4%) compared to those who did not (26.7%). The results of this study are inconclusive and have not determined whether preoperative chemotherapy results in better long-term survival for cStage Ⅳ rectal cancer patients. However, preoperative chemotherapy might contribute to higher operative curability.

Visualisation of cell cycle modifications by X-ray irradiation of single HeLa cells using fluorescent ubiquitination-based cell cycle indicators

To explore the effects of X-ray irradiation on mammalian cell cycle dynamics, single cells using the fluorescent ubiquitination-based cell cycle indicator (Fucci) technique were tracked. HeLa cells expressing Fucci were used to visualise cell cycle modifications induced by irradiation. After cultured HeLa-Fucci cells were exposed to 5 Gy X-rays, fluorescent cell images were captured every 20 min for 48 h using a fluorescent microscope. Time dependence of the fluorescence intensity of S/G2 cells was analysed to examine the cell cycle dynamics of irradiated and non-irradiated control cells. The results showed that irradiated cells could be divided into two populations: one with similar cell cycle dynamics to that of non-irradiated cells, and another displaying a prolonged G2 phase. Based on these findings, it is proposed in this article that an underlying switch mechanism is involved in cell cycle regulation and the G2/M checkpoint of HeLa cells.

Cataract survey in the local area using photographic documentation

An epidemiological survey of cataract was performed in a limited local population. 1,020 individuals over 40 years of age were examined. The crystalline lens findings were documented by both Scheimpflug and retroillumination photography. Cataractous changes were classified into three groups according to early senile changes, incipient cataractous changes and only prominent cataractous changes. Forms of opacification were classified as cortical, subcapsular, nuclear, mixed type and others. The percent prevalence of cataracts including early senile changes was 33.9% in the 40-year-old population, 62.8% in the 50, 76.2% in the 60, 84.0% in the 70 and 100% for those in their 80s. Prominent cataractous opacification was 1.6% in the 40-year-old population, 3.1% for those in their 50s, 19.0% in their 60s, 28.6% in their 70s and 57.1% in their 80s, respectively. Until age 60, the type of opacification was mainly cortical alone; however, after age 70, cortical opacity accompanied by nuclear and/or capsular opacities increased. The pure nuclear type increased in individuals over 70.

Population genetic structure and Wolbachia infection in an endangered butterfly, Zizina emelina (Lepidoptera, Lycaenidae), in Japan

Zizina emelina (de l'Orza) is listed on Japan's Red Data List as an endangered species because of loss of its principal food plant and habitat. We compared parts of the mitochondrial and nuclear genes of this species to investigate the level of genetic differentiation among the 14 extant populations. We also examined infection of the butterfly with the bacterium Wolbachia to clarify the bacterium's effects on the host population's genetic structure. Mitochondrial and nuclear DNA analyses revealed that haplotype composition differed significantly among most of the populations, and the fixation index F ST was positively correlated with geographic distance. In addition, we found three strains of Wolbachia, one of which was a male killer; these strains were prevalent in several populations. There was linkage between some host mitochondrial haplotypes and the three Wolbachia strains, although no significant differences were found in a comparison of host mitochondrial genetic diversity with nuclear genetic diversity in Wolbachia-infected or -uninfected populations. These genetic analyses and Wolbachia infection findings show that Z. emelina has little migratory activity and that little gene flow occurs among the current populations.

Risk Factors for Anastomotic Leakage After Intersphincteric Resection Without a Protective Defunctioning Stoma for Lower Rectal Cancer

BACKGROUND

Intersphincteric resection (ISR) is performed as an alternative to abdominoperineal resection for super-low rectal cancer. The purpose of this study was to evaluate risk factors for anastomotic leakage (AL) after ISR without a defunctioning stoma for lower rectal cancer.

METHODS

Between 1995 and 2012, 135 consecutive patients with lower rectal cancer underwent curative ISR without a protective defunctioning stoma. Univariate and multivariate analyses were performed to determine the risk factors for AL.

RESULTS

The radiological and symptomatic AL rate was 17.0 % (23/135). Univariate analysis demonstrated that male sex (P = 0.030), preoperative chemotherapy (P = 0.016), partial ISR (P < 0.001), lateral lymph-node dissection (P = 0.042), distal tumor distance from the dentate line (P = 0.007), and straight reconstruction (P < 0.001) were significantly associated with AL. Severe AL requiring re-laparotomy developed in 13 (9.6 %) patients. Univariate analysis demonstrated that male sex (P = 0.006), partial ISR (P < 0.001), distal tumor distance from the dentate line (P = 0.002), and straight reconstruction (P < 0.001) were significantly associated with AL requiring relaparotomy. Multivariate analysis demonstrated that partial ISR [odds ratio (OR) 6.701; P = 0.001] and straight reconstruction (OR 5.552; P = 0.002) were independently predictive of AL.

CONCLUSIONS

Partial ISR and straight reconstruction increased the risk of AL after ISR without a protective defunctioning stoma. A defunctioning stoma might be mandatory in patients with the risk factors identified in this analysis.

A clinicopathological study of perineural invasion and vascular invasion in oral tongue squamous cell carcinoma

The risk factors for recurrence of head and neck cancer are classified as being of high or intermediate risk. Those of intermediate risk include multiple positive nodes without extracapsular nodal spread, perineural/vascular invasion, pT3/T4 primary tumours, and positive level IV/V nodes. However, little evidence is available to validate these intermediate risk factors. We analyzed perineural/vascular invasion in 89 patients who underwent radical surgery for oral tongue squamous cell carcinoma, whose records were reviewed retrospectively. Perineural invasion was found in 27.0% of cases and vascular invasion in 23.6%; both had a strong relationship with histopathological nodal status (P = 0.005). The 5-year disease-specific survival (DSS) and overall survival rates of patients with perineural invasion were significantly lower than those of patients without perineural invasion (P < 0.001 and P = 0.002, respectively). The 5-year DSS of UICC stage I and II cases with perineural/vascular invasion was significantly lower than those without (P < 0.001 and P = 0.008, respectively). Perineural invasion and vascular invasion are risk factors for regional metastasis and a poor prognosis. We recommend elective neck dissection when perineural/vascular invasion is found in clinical stage I and II cases. The accumulation of further evidence to consider intermediate risks is required.

Fast calculation method of a CGH for a patch model using a point-based method

Holography is three-dimensional display technology. Computer-generated holograms (CGHs) are created by simulating light propagation on a computer, and they are able to display a virtual object. There are mainly two types of calculation methods of CGHs, a point-based method and the fast Fourier-transform (FFT)-based method. The FFT-based method is based on a patch model, and it is suited to accelerating the calculations as it calculates the light propagation across a patch as a whole. The calculations with the point-based method are characterized by a high degree of parallelism, and it is suited to accelerating graphics processing units (GPUs). The point-based method is not suitable for calculation with the patch model. This paper proposes a fast calculation algorithm for a patch model with the point-based method. The proposed method calculates the line on a patch as a whole regardless of the number of points on the line. When the proposed method is implemented on a GPU, the calculation time of the proposed method is shorter than with the point-based method.

Differential diagnosis of liver tumours using intraoperative real-time tissue elastography

Background

Real-time tissue elastography is an innovative tool that informs the surgeon about tissue elasticity by applying the principle of ultrasonography. The aim of this study was to investigate the accuracy of intraoperative real-time tissue elastography (IORTE) for the detection and characterization of liver tumours.

Methods

Between October 2010 and November 2011, IORTE was performed for liver lesions after the completion of routine B-mode intraoperative ultrasonography (IOUS). The elasticity images of all tumours, except those of cysts, were classified into six categories according to modified criteria (types 1–6), according to the degree of strain contrast with the surrounding liver. The concordance of IORTE with pathological examination of the tumour, B-mode IOUS and clinical diagnosis after follow-up was assessed.

Results

Images were obtained from 92 hepatocellular carcinomas (HCCs), 92 adenocarcinomas, 19 other malignant tumours and 18 benign tumours in 158 patients. Using a minilinear probe, 73 of 88 HCCs were classified as having a ‘HCC pattern’ (type 3, 4 or 5), resulting in a sensitivity of 83·0 per cent, a specificity of 67·2 per cent and an accuracy of 73·7 per cent. Some 66 of 90 adenocarcinomas were classified as ‘adenocarcinoma pattern’ (type 6), resulting in a sensitivity of 73·3 per cent, specificity of 95·1 per cent and accuracy of 85·9 per cent. IORTE detected seven new lesions (8 per cent).

Conclusion

IORTE is useful for the detection and characterization of liver tumours.