The Ethics Committee of Kitasato University Hospital approved the present study
Indications for TAE were decided at angiography based on active extravasation or tumour staining of the known tumour. When TAE was indicated, a microcatheter was advanced into the artery whose blood supply covered the area of extravasation as well as the area of tumour staining.
Second, patients who bled from the duodenum or small/ large intestine were chosen as candidates for use of IPM/CS. Subsequently, the indication for IPM/CS was determined when one of the following findings was observed on the angiogram: 1) the bleeding artery was too small to place the metallic coil; 2) extravasation was observed, but the specific bleeding origin artery was hard to detect; or 3) tumour staining, vascular encasement, or vascular proliferation relating to the neoplasm was observed, although no extravasation was observed. These criteria were defined based on speculation that the size of the IPM/CS particle, mainly distributed from 10 to 70 μm (Aihara 1999a; Aihara 1999b), may be adequate to embolise bleeding from small vessels. Patients who showed unstable vital signs or were in shock were excluded from the indication of IPM/CS.
Seven patients (five men and two women) underwent 11 TAE procedures using IPM/CS for duodenal or small/large intestinal bleeding from neoplasms from January 2004 to December 2011. Their ages ranged from 43 to 73 years (mean age: 59.2 ± 11.0 years). Four patients had repeat TAE using IPM/CS.
All patients owned the neoplasm in the large or small intestine at the time of intestinal bleeding”. The median time from the onset of bleeding to angiography was 6 days, ranging from 0 to 20 days. The origins of bleeding included invasion of pancreatic cancer to the duodenum (n = 2), metastasis of renal cell carcinoma to the pancreas invading to the duodenum (n = 1), invasion of cervical cancer to the rectum (n = 1), colon cancer (n = 1), and malignant lymphoma of the small intestine (n = 2). No patient was a candidate for operative haemostasis due to progression of the neoplasm (n = 6) or pulmonary thromboembolism (n = 1) at the time of bleeding. Four of seven patients had endoscopy before angiography to attain haemostasis. Two of these four patients had rebleeding after endoscopic thermocoagulation. In the other two patients, the endoscope could not reach the bleeding sites because of narrowing of the intestinal lumens caused by the tumours.
First, a 5 F introducer was placed in the right or left femoral artery. Angiography of the celiac artery, superior mesenteric artery (SMA), or inferior mesenteric artery (IMA) was performed using a 5 F cobra or shepherd-type catheter by injecting 20 to 25 ml of contrast medium at a rate of 4.0 to 5.0 ml/sec for the SMA and celiac artery and 10 ml to 15 ml at a rate of 2.0 to 2.5 ml/sec for the IMA.
Preparation and deployment of the IPM/CS mixture
A mixture of 0.5 g IPM/CS and 5 ml of contrast medium was prepared for use as an embolic agent. Five millilitres of contrast medium was put in a vial containing 0.5 g IMP/CS and the mixture was stirred. The mixture was then drawn into a 5-ml syringe and pumped gently with a 2.5-ml syringe connected to the 5-ml syringe through a three-way stopcock. This mixture was injected through a microcatheter placed at the artery whose blood supply covered the tumour staining until the extravasation disappeared or stasis of blood flow to the tumour staining was observed.
The TAE procedure was deemed technically successful when disappearance of extravasation or tumour staining was attained at the time of the procedure.
All patients were carefully followed up with clinical and laboratory examinations to check for rebleeding and complications from embolisation for at least 1 week at the hospital. Rebleeding was deemed positive when melena, haematochezia, or haematemesis was observed. Haematologic parameters, including the total number of transfused units of packed red blood cells and averaged haemoglobin for 7 days, were compared before and after TAE to assess the effect of TAE.
Each patient was assessed for peritoneal signs and symptoms such as tenderness, nausea, diarrhoea, fever, and marked change in bowel sounds after embolisation to determine the occurrence of ischaemic injury every day for at least 1 week. Laboratory ischaemic evidence was evaluated by assessing the increase in white blood cell count (WBC), creatine phosphokinase (CPK), and lactate dehydrogenase (LDH) by comparison of averaged data of the patients for 7 days before and after TAE. In evaluating the volume of blood transfusion, averaged haemoglobin, WBC, CPK, and LDH for the two patients who had repeat TAE within 24 hours after the first TAE (patients 2 and 6), the data until the first TAE were deemed the data before TAE, and data after the second TAE were deemed the data after TAE. One patient underwent upper gastrointestinal endoscopy after TAE to explore haemostasis and to check for complications (patient 3). Two patients were transferred to another hospital to continue treatment for cancer after 44 and 339 days, respectively. The period of clinical follow-up to check for rebleeding ranged from 37 to 339 days after TAE (median, 163 days).
The Wilcoxon signed-rank test was used to compare laboratory data and blood transfusion volume before and after TAE using JMP 7.0 software (2007 SAS institute, Inc., Cary, NC).