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E J Derksen

Publications and source records attributed to E J Derksen.

8 recordsLinked to original sources

Kinetics and dosimetry of iodine-131-labelled antibody fragments after local administration in patients with rectal cancer.

In 11 patients with rectal cancer, a mixture of F(ab')2 fragments of anti-carcinoembryonic antigen and anti-CA 19.9 labelled with a diagnostic dose of iodine-131 (3-10 MBq) was administered submucosally around the tumour. In this study, the local kinetics in and the dose to the rectal wall, the whole body kinetics and the effective dose equivalent are presented. The early disappearance of the activity from the injection spot was characterized by a T1/2 of 21 h. Initially, about 50% of the plasma activity was due to free 131I. After 4 h, the plasma activity was almost completely protein bound (86%). Maximum plasma activity was observed after the 2nd day. From 72 h p.i., the plasma activity decreased with a T1/2 of 53 h. In the first 24 h, 14% of the injected dose was excreted in the urine and within 4 days about half of the administered activity. The absorbed radiation dose to the rectal wall was estimated to be 0.2 Gy/MBq, presuming a 20 cm3 distribution volume. The dose to the bone marrow was 0.2 mGy/MBq or 0.4 mGy/MBq, assuming a homogeneous tracer distribution or equal blood and bone marrow activity concentrations, respectively. The effective dose equivalent is 1.9 mSv/MBq, mainly determined by the dose to the rectal wall and to a lesser extent by the dose to the remaining body. Postulating comparable kinetics, 123I- or 111In- or 99mTc-labelled fragments would result in 4-25-fold lower effective dose equivalents.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged

Anal sphincter imaging in fecal incontinence using endosonography.

Clinical anal examination, manometry (resting and squeeze pressures), and single-fiber electromyography were compared with endosonography of the anal sphincters in 14 patients with fecal incontinence. Technical aspects of the procedure and normal imaging of the puborectal muscle and both sphincters were defined. Defects in both sphincters were seen in nine patients. The defect is visualized as a clear discontinuity in the muscular ring. Compared with the conventional studies, anal endosonography gave significant information in six patients (four male patients after perianal surgery and two women), showing sphincter defects in five patients and integrity of the sphincters in another one. This information obtained by endosonography was important in understanding the type and extension of the lesion and deciding upon the surgical repair. Anal endosonography is an imaging technique of the sphincters that can assess their integrity in fecal incontinence.

Adult

Intraluminal ultrasound of rectal tumours: a prerequisite in decision making.

The use of intraluminal ultrasound (IUS) as a staging technique was evaluated in 58 patients with a rectal tumour. Thirty-four patients had a rectal carcinoma, four had a local recurrence after a previous anterior resection and 20 other patients had a villous adenoma. IUS assessment of rectal wall invasion, infiltration into adjacent organs, and the presence of perirectal lymph node involvement was compared with the definitive histological findings. In 90% of all patients the pre-operative local tumour staging was predicted correctly. In 38 patients with a rectal carcinoma the overall accuracy for the T grade was 84%. The sensitivity for the detection of perirectal fat infiltration was 91%, with a specificity of 70% and a negative predictive value of 78%. The accuracy in predicting direct infiltration into adjacent organs was 100% (n = 5). In the four patients with a local recurrence, the diagnosis was suspected by means of IUS and confirmed by biopsies. Extraluminal tumour growth was predicted correctly in all cases, with extension into the coccygeal bone in one patient. IUS identified lymph nodes in 29 of 38 cases, with a sensitivity of 57% and a specificity of 76%. All 20 villous adenomas were correctly staged as non-infiltrative tumours. After transmural excision, three adenomas proved to contain a completely removed T1 carcinoma. IUS is the most accurate tool in predicting the depth of local tumour invasion and needs a place in the preoperative screening programme in patients with a rectal tumour, as well as in the postoperative follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma, Villous

Cryosurgery for locally recurrent rectal cancer.

Locally recurrent rectal cancer is, in most cases, unresectable and incurable. Palliative treatment is warranted in many cases because of the presence of severe distressing symptoms. In recurrent disease, intraluminal cryotherapy is an option for palliation. Twenty patients with local recurrence after anterior resection were treated palliatively with cryosurgery for their local symptoms. Six patients had previously had a colostomy before they were referred for palliative treatment. Thirteen patients had more than one symptom. Distant metastases were present in ten cases. The beneficial effect of cryosurgery was evident after two to three sessions. In nine patients cryotherapy achieved complete relief of local symptoms. In these patients the symptom free interval varied from 1 to 24 months (median 11 months); five patients died of disease without local symptoms. Three of these nine patients underwent a bowel diversion at a later stage because of complete stenosis. The number of treatment sessions in this group of patients varied from three to 14. The palliative index varied from 37 to 100% (mean 78%). In nine patients cryotherapy of the local recurrence gave no relief at all. Our results show that in almost half of the patients cryosurgery can palliate local complaints resulting from recurrent tumor growth after anterior resection.

Aged

Retrosternal dislocation of the clavicle.

Retrosternal dislocation of the clavicle is an uncommon injury which may affect the mediastinal structures in a life-threatening way. Therefore, computed tomography is mandatory. Manipulation in the acute situation is the treatment of choice. In case of failure or old dislocation, open reduction with stabilization of the joint is required. The literature on this subject has been reviewed and an additional two cases are reported.

Adult

Qualitative and quantitative kinetics of submucosally administered antibody fragments in patients with rectal carcinoma: the detection of lymph node metastasis in relation to local tracer diffusion.

Immunoscintigraphy after submucosal administration of a mixture of 131I-anti-CEA and 131I-anti-CA-19-9 around the tumor in patients with rectal carcinoma may improve pre-operative staging and may contribute to the selection of patients eligible for local treatment. However, visual discrimination of local lymph node metastasis appears unreliable, partly because of scatter from the injection site and substantial diffusion of the radiotracer into the interstitium. Analysis of the diffusion profile, however, may improve the sensitivity and accuracy of this immunoscintigraphic approach.

Aged