Experience in qualitative and quantitative FDG PET in follow-up of patients with suspected recurrence from head and neck cancer.

We evaluated positron emission tomography (PET) with 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG) in the detection of recurrent head and neck cancer, and compared visual and quantitative interpretation of PET images for their accuracy in the identification of tumour recurrence. Sixty-two FDG PET studies were performed in 56 patients having a total of 81 lesions, which were clinically suspected for recurrent carcinoma of the head and neck. The PET images were interpreted visually, and tracer uptake was quantitated as the standardised uptake value adjusted to body weight (SUV). Sensitivity of visual interpretation of the PET images for the presence of malignancy ranged from 84 to 95%, and specificity from 84 to 93%, respectively, depending on the selected scheme for grading of the lesions. Malignant lesions accumulated significantly more FDG than the benign ones (the median SUVs were 6.8 and 3.3, respectively, P<0.001). However, there was a wide overlap of the FDG uptake values between these two groups. Hence, the highest accuracy of quantitative analysis in correct identification of tumour recurrence (75% at Receiver Operating Curve analysis) was inferior to that of visual analysis (89%). FDG PET is feasible for the detection of recurrent head and neck cancer. Although quantitation of FDG uptake using SUV shows significantly higher tracer concentrations for malignant than benign lesions, the wide overlap of individual SUVs between these two groups is a serious concern in diagnostic evaluation. Therefore, in clinical practice it may be preferable to identify the presence of tumour recurrence within this patient group by qualitative interpretation of the PET images.

Cystic gastric leiomyoma--a diagnostic pitfall.

A case of a 74-year-old woman with a cystic calcified leiomyoma of the stomach is presented. The cyst was initially interpreted and treated as a pancreatic pseudocyst with repeated punctures and cystogastrostomy. Due to failure of elimination of the cyst, and because of infection, the patient underwent surgery. A discussion of the differential diagnoses and treatment is presented.

[Strangulation ileus of the small intestine--the significance of CT in the diagnostic procedure]. / Strangulationsileus af tyndtarm--betydningen af CT i den diagnostiske proces.

We report a case of strangulating small bowel obstruction due to an adhesive band. The patient had a normal plain abdominal X-ray, but CT-scanning unveiled signs of strangulating obstruction. The value of CT is discussed and we conclude that CT should be performed if intestinal strangulation is suspected but clinical and plain film findings are non-specific.

Identification of four chicken gastrins, obtained by processing at post-Phe bonds.

Chicken antrum was found to contain 7 nmol/g of carboxyamidated gastrin/CCK-like peptides. The predominant chicken gastrin (so named due to the antral origin) contained 53 amino acid residues: DWPEPPSQEQ QQRFISRFLP HVFAELSDRK GFVQGNGAVE ALHDHFYPDW MDF-NH2. Three smaller (less abundant) forms corresponded to the 30-, 21-, and 7-residue carboxyamidated C-terminal fragments. The major part was sulfated at the tyrosine residue in position seven from the C-terminus. A lower isoelectric point and abrupt termination of the sequencing suggest that some of the peptides had an isoAsp-Gly bond instead of an Asn-Gly bond. The three shorter forms were all derived from the precursor by post-Phe cleavages. This cleavage pattern suggests a processing enzyme specific for bonds between Phe and moderately hydrophobic residues.