Computer-aided detection in computed tomography colonography: current status and problems with detection of early colorectal cancer

PURPOSE: The aim of this study was to evaluate the usefulness of computer-aided detection (CAD) in diagnosing early colorectal cancer using computed tomography colonography (CTC). MATERIALS AND METHODS: A total of 30 CTC data sets for 30 early colorectal cancers in 30 patients were retrospectively reviewed by three radiologists. After primary evaluation, a second reading was performed using CAD findings. The readers evaluated each colorectal segment for the presence or absence of colorectal cancer using five confidence rating levels. To compare the assessment results, the sensitivity and specificity with and without CAD were calculated on the basis of the confidence rating, and differences in these variables were analyzed by receiver operating characteristic (ROC) analysis. RESULTS: The average sensitivities for the detection without and with CAD for the three readers were 81.6% and 75.6%, respectively. Among the three readers, only one reader improved sensitivity with CAD compared to that without. CAD decreased specificity in all three readers. CAD detected 100% of protruding lesions but only 69.2% of flat lesions. On ROC analysis, the diagnostic performance of all three readers was decreased by use of CAD. CONCLUSION: Currently available CAD with CTC does not improve diagnostic performance for detecting early colorectal cancer. An improved CAD algorithm is required for detecting flat lesions and reducing the false-positive rate.     

Midterm results of stent-graft repair of acute and chronic aortic dissection with descending tear: the complication-specific approach

BACKGROUND: Endovascular stent-graft placement for the treatment of patients with aortic dissection is emerging as an attractive alternative to conventional cardiac operations. However, there has been no report of longer-term follow-up. The purpose of this study is to describe our midterm results with endovascular stent-graft repair for the treatment of patients with aortic dissections. METHODS: Thirty-eight patients with aortic dissections with descending tears were treated with endovascular stent-grafting. Ten patients had acute type A, 14 patients had acute type B, and 14 patients had chronic type B dissection. Stent grafts fabricated from expanded polytetrafluoroethylene-covered Z stents were placed to close entry tears in all patients through the delivery systems introduced from the femoral or the iliac arteries. RESULTS: Two patients with complicated acute type B dissection, who would have required surgical intervention, died within 30 days of the procedure, although no other patients died within the same period. There were no late deaths during the mean follow-up period of 27 months. Early and late complication rates were 33% and 36%, respectively, in patients with acute dissection, whereas rates were 4% and 0% (P <.05 vs patients with acute dissection) in patients with chronic dissection. CONCLUSIONS: Entry closure with endovascular stent-graft placement may be a safe and effective method for the treatment of patients with aortic dissection. It could be an alternative to conventional surgical intervention in selected patients with chronic dissection. However, strict patient selection and close follow-up seem mandatory in patients with acute dissection receiving Z stent-based stent-grafts. Stent-graft repair should be delayed for acute type B dissection without complications.     

Endoscopic submucosal dissection and preoperative assessment with endoscopic ultrasonography for the treatment of rectal carcinoid tumors

Background

Rectal carcinoid tumors 10 mm in diameter or smaller located within the submucosal layer can be cured by local excision including endoscopic treatment. But complete resection of these tumors with endoscopic polypectomy is difficult. This study aimed to evaluate the usefulness of endoscopic submucosal dissection (ESD) and endoscopic ultrasonography (EUS) for the treatment of rectal carcinoid tumors.

Methods

In this study, 22 rectal carcinoid tumors in 21 patients were evaluated with EUS and treated using ESD from January 2004 to December 2008.

Results

The mean size of the resected tumors was 6.1 mm (range, 2.0–10 mm) on histopathologic evaluations. When the sizes of the tumors shown by EUS and histopathologic evaluation were compared, the mean values were not significantly different. All the tumors were located within the submucosal layer, and the accuracy of the preoperative depth determination with EUS was 100% (22/22). The mean duration of the ESD procedure was 37 min (range, 20–71 min). The overall rate of en bloc resection with ESD was 100% (22/22). Although postoperative bleeding occurred in two cases (9%), both cases were successfully managed by endoscopic hemostasis. No perforation or recurrence was observed during the mean follow-up period of 30 months (range, 7–66 months).

Conclusions

Endoscopic submucosal dissection and preoperative assessment with EUS are effective for treating rectal carcinoid tumors and enabling en bloc resection.     

Endoscopic submucosal dissection with a combination of small-caliber-tip transparent hood and flex knife for large superficial colorectal neoplasias including ileocecal lesions

Background

Large superficial neoplasias of the ileocecal region pose an increased degree of complexity for endoscopic resection. This study aimed to evaluate the safety and efficacy of endoscopic submucosal dissection (ESD) for large superficial colorectal neoplasias including ileocecal lesions.

Methods

A total of 33 superficial colorectal neoplasias, including eight neoplasias in the ileocecal region, were treated with ESD from December 2005 to April 2009. Therapeutic efficacy, complications, and follow-up results were retrospectively evaluated among three groups: ileocecal region, colon, and rectum.

Results

The mean size of all resected neoplasias was 35 ± 15 mm (range, 20–80 mm) and that of all resected specimens was 41 ± 15 mm (range, 23–82 mm). The mean procedural time was 121 ± 90 min (range, 22–420 min). The difference in mean values among the three groups was not significant. The overall rate of en bloc resection was 91% (30/33). Histopathologically, both the lateral and vertical margins in the specimens resected en bloc tested negative (30/30). The rate for en bloc resection in the ileocecal region did not differ significantly from that for the other two groups (p = 0.20 compared with the rate for the colon and p = 0.12 compared with the rate for the rectum). Complications such as perforation and postoperative bleeding did not occur in the ileocecal group. No recurrence was observed in any cases during the mean follow-up period of 20 ± 12 months (range, 4–44 months).

Conclusions

The ESD approach is safe and effective for treating large superficial neoplasias of the ileocecal region such as other colorectal neoplasias.     

Endoscopic submucosal dissection with a combination of small-caliber-tip transparent hood and flex knife for superficial esophageal neoplasia. Is it safe for elderly patients?

Background

Safety and efficacy of endoscopic submucosal dissection (ESD) for esophageal neoplasias have not been adequately investigated in elderly patients. This study was designed to evaluate the safety and efficacy of ESD for esophageal neoplasias in elderly patients.

Methods

Fifty-three superficial esophageal neoplasias treated with ESD using a combination of small-caliber-tip transparent hood and flex knife from May 2006 to June 2009 were divided into elderly group (aged 70 years or older: 25 lesions in 23 patients) and nonelderly group (younger than aged 70 years: 28 lesions in 25 patients). Therapeutic efficacy, complications, and follow-up results were evaluated retrospectively.

Results

The history of cerebral infarction or cardiopulmonary disease and the usage of antiplatelet agents or anticoagulants were significantly higher in elderly group (p 0.0050 and p 0.0013, respectively). Median procedural times in the elderly group and the nonelderly group were 93 ± 53 (range, 42–235) min and 95 ± 55 (range, 40–230) min (p 0.73), respectively. Median sizes of the neoplasias and the resected specimens were 14 ± 11 (range, 5–45) mm and 15 ± 17 (range, 5–83) mm (p 0.56), and 35 ± 12 (range, 18–60) mm and 38 ± 17 (range, 18–90) mm (p 0.38), respectively. En bloc resection rate was 100% in each group. Body temperature and white blood cell counts of the next day after ESD were significantly higher in the nonelderly group than in the elderly group (p 0.0087 and p 0.0043, respectively). There were no complications, such as postoperative bleeding or perforation, in each group. The median follow-up period of 23 ± 10 (range, 4–35) months in the elderly group revealed no local or distant metastasis.

Conclusions

ESD with a combination of small-caliber-tip transparent hood and flex knife is a safe and effective treatment for superficial esophageal neoplasia in elderly and nonelderly patients.     

Progressive multifocal leukoencephalopathy in an HTLV-I carrier

This report describes a previously 28-year-old healthy woman, identified as an asymptomatic human T-lymphotropic virus type I (HTLV-I) carrier, who developed both progressive multifocal leukoencephalopathy (PML) and Pneumocystis jiroveci pneumonia. For diagnostic confirmation of PML, stereotactic brain biopsy demonstrated multiple demyelinating lesions with the presence of JC viral antigen. Intramuscular alpha-interferon therapy for 2 weeks brought considerable neurologic improvement. Three years later, the patient developed lymphoma-type of adult T-cell leukemia, suggesting that HTLV-I carrier might be one of the underlying diseases of PML.     

CSF leakage and anosmia in aneurysm clipping of anterior communicating artery by basal interhemispheric approach

We studied the incidence of postoperative infection related to CSF leakage and anosmia in basal interhemispheric approach (BIH). Between April, 1990 to March, 2009, 142 cases of anterior communicating (Acom) aneurysm including both unruptured and ruptured have been treated by clipping surgery using BIH. We retrospectively obtained clinical informations from medical records and video records about infectious complications, CSF leakage of cerebrospinal fluid (CSF), olfactory dysfunction and intraoperative findings of damage to the olfactory nerve. In most cases (139 patients, 97%), frontal sinus were opened at craniotomy. Of all, CSF rinorrhea occurred in 4 cases (2.8%), and meningitis in 6 cases. There was only one patient who sufferd from meningitis due to CSF rinorrhea. All that patients recovered completely without deficit. Anosmia occurred in 6 cases (4.2%), and intraoperative injuries in 4 cases (2.8%). There was only one patient in whom anosmia was consistent with nerve injury. In conclusion, BIH is an appropriate procedure for infection risk control in Acom aneurysm surgery. It is difficult to avoid olfactory dysfunction completely, even if olfactory nerves are preserved in form.     

Patient-controlled epidural analgesia combined with patient-controlled intravenous analgesia for postoperative analgesia after Miles' operation for rectal cancer

A 69-year-old woman (156 cm, 53 kg) underwent a Miles' operation, total hysterectomy, resection of vagina, and thigh flap to vulva for rectal cancer. Before general anesthesia, an epidural catheter was inserted at T11-12 interspace, and 1.5% mepivacaine 7ml was administered. Sensory block level spread from T4 to L1. Anesthesia was induced with propofol and maintained with sevoflurane in air oxygen mixture. Operation was performed uneventfully. After the operation, postoperative analgesia was achieved with patient-controlled epidural analgesia (PCEA). The epidural solution of 0.06% ropivacaine with 4 microg x ml(-1) fentanyl and 20 microg x ml(-1) was connected to a PCA pump (i-Fuser, JMS, Japan) that was programmed as an 8 ml initial bolus, 4 ml x hr(-1) basal infusion, 2 ml bolus dose, and 10-min lockout interval. Although abdominal pain was well controlled by PCEA, intractable pain in the pelvic nerve region existed. Patient-controlled intravenous analgesia (IV-PCA) with fentanyl, ketamine, and lidocaine was added to PCEA. Then excellent pain relief was obtained without any side effects such as nausea, vomiting, drowsiness, and respiratory depression. It could be useful to use IV-PCA together with PCEA when wide spread postoperative analgesia is necessary.     

Polarized osteoclasts put marks of tartrate-resistant acid phosphatase on dentin slices--a simple method for identifying polarized osteoclasts

Osteoclasts form ruffled borders and sealing zones toward bone surfaces to resorb bone. Sealing zones are defined as ringed structures of F-actin dots (actin rings). Polarized osteoclasts secrete protons to bone surfaces via vacuolar proton ATPase through ruffled borders. Catabolic enzymes such as tartrate-resistant acid phosphatase (TRAP) and cathepsin K are also secreted to bone surfaces. Here we show a simple method of identifying functional vestiges of polarized osteoclasts. Osteoclasts obtained from cocultures of mouse osteoblasts and bone marrow cells were cultured for 48 h on dentin slices. Cultures were then fixed and stained for TRAP to identify osteoclasts on the slices. Cells were removed from the slices with cotton swabs, and the slices subjected to TRAP and Mayer's hematoxylin staining. Small TRAP-positive spots (TRAP-marks) were detected in the resorption pits stained with Mayer's hematoxylin. Pitted areas were not always located in the places of osteoclasts, but osteoclasts existed on all TRAP-marks. A time course experiment showed that the number of TRAP-marks was maintained, while the number of resorption pits increased with the culture period. The position of actin rings formed in osteoclasts corresponded to that of TRAP-marks on dentin slices. Immunostaining of dentin slices showed that both cathepsin K and vacuolar proton ATPase were colocalized with the TRAP-marks. Treatment of osteoclast cultures with alendronate, a bisphosphonate, suppressed the formation of TRAP-marks and resorption pits without affecting the cell viability. Calcitonin induced the disappearance of both actin rings and TRAP-marks in osteoclast cultures. These results suggest that TRAP-marks are vestiges of proteins secreted by polarized osteoclasts.     

Right lung cancer with right aortic arch

An abnormal shadow was detected on chest X-ray mass screening in an asymptomatic 63-year-old man. The further examinations revealed the shadow to be primary lung cancer (Rt. S6. adenocarcinoma, cT2N0M0, c-stage IB) with right aortic arch. We used 3 dimentional-computed tomography (3D-CT) to assess an anatomical feature of vessels in detail. The right lower lobectomy and the dissection of medi astinal lymph nodes was performed. We confirmed no abnormal anatomy of pulmonary artery and vein at surgery, and it was possible to perform right lower lobectomy with the common procedure. Since lymph node was found by intraopetrative pathological examination, since no metastasis from interlobar to subcarinal lymph node was found, we did not perform dissection of upper mediastinal dissection, which was equivalent to ND2a lymph nodes dissection of the left lung cancer in General Rule for Clinical and Pathological Record of Lung Cancer. The patient with right aortic arch is known to have variant anatomy of other intrathoracic vessels occasionally. 3D-CT was quite useful in assessing anatomical feature, and enabled us to perform safe operation.