Detection of distant metastases in breast cancer patients: Comparison between [18F]-fluorodeoxyglucose positron emission tomography and conventional imaging

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Background: The presence of distant metastases is a key prognostic factor in breast cancer patients and plays a central role in therapeutic decisions. To detect distant metastases, chest X-ray, abdominal ultrasound and bone scintigraphy are performed as standard of care in many centers. In various tumors, [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) detects metastatic disease with high accuracy, but the diagnostic value in breast cancer still needs to be defined. The aim of this study was to compare the diagnostic performance of FDG-PET with conventional imaging. Methods: In 119 breast cancer patients who presented for restaging, whole-body FDG-PET was compared with chest X-ray, bone scintigraphy and abdominal ultrasound. Each imaging modality was independently assessed and classified as ‘negative’, ‘equivocal’ and ‘positive’ for metastasis. The imaging results were compared with histopathology and clinical follow-up including follow-up imaging procedures which together served as the reference standard. Results: For findings classified as ‘positive’, FDG-PET detected distant metastases with a sensitivity of 87% and a specificity of 83%. In contrast, the sensitivity and specificity of combined conventional imaging procedures was 43% and 98%, respectively. The positive and negative predictive values were 89% and 82% for FDG-PET and 96% and 69% for conventional imaging. Combining ‘equivocal’ and ‘positive’ results, the sensitivity and specificity of FDG-PET was 93% and 76%, respectively, compared to 61% and 86% for conventional imaging. The positive and negative predictive values were 86% and 88% for FDG-PET versus 77% and 75% for conventional imaging. Conclusions: FDG-PET is superior to conventional imaging procedures for detection of distant breast cancer metastases. However, the use of computed tomography (CT), particularly in combined PET/CT, needs to be addressed in future studies comparing anatomical vs. metabolic staging procedures in breast cancer patients.

No significant financial relationships to disclose.

[Cystectomy for indications other than bladder cancer]

A cystectomy for indications other than transitional cell cancer of the bladder or general bladder cancer is frequently performed in cooperation with other surgical specialties such as general surgery or gynecology. In these cases the urological procedure as well as the oncological and surgical concepts of other specialties have to be combined. We studied our cystectomy patients who had undergone such a combined procedure for a non-urothelial indication concerning perioperative and postoperative complications.A total of 204 cystectomies were performed by the Department of Urology at the University of Hamburg, Germany between 1995 and 2003. Bladder cancer was the indication for cystectomy in 162 patients, but 42 patients had a non-urothelial indication for this procedure. These patients included 12 cases of advanced rectal cancer, 9 cases of advanced cervical cancer, 6 cases of advanced sigmoid cancer, 4 cases of advanced prostate cancer, 1 case of prostate sarcoma, 5 cases of complex vesicointestinal fistulae, 2 cases of urachal cancer, 1 leiomyosarcoma, 1 rhabdomyoma, and 1 rhabdomyosarcoma, respectively. Perioperative and postoperative complications of those patients were compared to patients who underwent cystectomy for transitional cell cancer of the bladder.Those 42 patients who underwent cystectomy for non-urothelial indications included 14 male and 28 female patients. The mean age was 58.2 years with a range of 3-78 years. For urinary diversion 30 ileum conduits, 4 sigma conduits, and 8 ileum neobladders were used. The mean operative time was 6.25 h. The mean blood loss was 2200 ml. An average of four red blood cell concentrates (RBC) had to be given. Postoperative hydronephrosis had to be treated in three (7%) patients unilaterally and in two (5%) patients bilaterally with a temporary nephrostomy. Postoperative urinary leakage lasting more than 30 days was found in two (5%) patients. A deep vein thrombosis as well as an ileus was found in five (12%) patients each, respectively. There was no perioperative mortality in this study. When comparing the complications of those patients with the 162 patients who underwent cystectomy for bladder cancer, the only significant difference ( p=0.033, chi-square test) was a higher ileus rate in the patients with cystectomy for a non-urothelial indication. Complications with cystectomy for non-urothelial indications are in large comparable to those for transitional cell carcinoma of the bladder. The higher ileus rate in non-urothelial patients can be explained by the more radical procedures in this group of patients. Even though the group of patients undergoing cystectomy for indications other than bladder cancer was small in this trial, the procedure is standardized in combination with other specialties. Larger patient numbers and a longer follow-up will lead to more data in this special group of patients.