Clinical experience with 99mTc-MIBI scintimammography in patients with breast microcalcifications.

The aim of this study was to evaluate whether 99mTc-MIBI scintimammography can improve the diagnostic value of mammography for the differentiation of benign and malignant breast microcalcifications. In 41 women presenting 45 clusters of microcalcifications, a 99mTc-MIBI scintimammography was performed before open biopsy. There were 24 malignant lesions (53%). The sensitivity (SE) and specificity (SP) of 99mTc-MIBI scintimammography were 58.3% and 81%, and the positive and negative predictive values (PPV, NPV) were 78% and 63%, respectively. SE and PPV increased for lesions over 10 mm and for the younger patients (under 50 years). No correlation was found between true positive uptake and breast cancer invasiveness: 69% (9/13) for invasive lesions and 45% (5/11) for noninvasive lesions (P = 0.48). 99mTc-MIBI scintimammography was more often positive in high grade than in low- or intermediate-grade ductal carcinoma in situ (P = 0.03). The results were analysed according to the morphologic aspect of the microcalcifications. 99mTc-MIBI scintimammography could not be used for routine evaluation of all the microcalcifications detected by mammography.

[Standards, options, and recommendation for external radiotherapy of prostatic cancer: evaluation of the effect of dosage]. / Standards, Options et Recommandations pour la radiothérapie externe des patients atteints de cancer de la prostate: évaluation de l'effet dose.

CONTEXT: The "Standards, Options and Recommendations" (SOR) collaborative project was initiated in 1993 by the Federation of the French Cancer Centres (FNCLCC), with the 20 French Regional Cancer Centres, several French public university and general hospitals, as well as private clinics and medical speciality societies. Its main objective is the development of serviceable clinical practice guidelines in order to improve the quality of health care and the outcome of cancer patients. The methodology is based on a literature review, followed by critical appraisal by a multidisciplinary group of experts. Draft guidelines are produced, then validated by specialists in cancer care delivery. OBJECTIVES: Produce clinical practice guidelines for the radiotherapy of prostate cancer using the methodology developed by the Standards, Options and Recommendations project. METHODS: The FNCLCC and the French Urology Association (AFU) designated the multidisciplinary group of experts. Available data were collected by a search of Medline and lists selected by experts in the group. A first draft of the guidelines was written, they validated by independent reviewers. RESULTS: The main recommendations are: 1/ a minimal dose of 70 Gy must be used, whatever the prognostic factors; 2/ it appeared that patients with favourable prognostic indicators (stage T1-2, PSA < or = 10 micrograms/L and Gleason score < or = 6) do not benefit from a dose escalation effect for doses over 70-74 Gy; 3/ patients with intermediate prognosis are the ones who benefit most from the dose escalation effect over 74 Gy, provided they receive exclusive radiation therapy; 4/ whenever possible, patients should be included in controlled trials designed to assess the effects of dose escalation and hormonotherapy.

[Standards, Options, and Recommendations for brachytherapy in patients with prostate cancer: efficacy and toxicity]. / Standards, Options et Recommandations pour la curiethérapie des patients atteints de cancer de la prostate: efficacité et toxicité.

CONTEXT: The "Standards, Options and Recommendations" (SOR) collaborative project was initiated in 1993 by the Federation of the French Cancer Centres (FNCLCC), with the 20 French Regional Cancer Centres, several French public university and general hospitals, as well as private clinics and medical specialty societies. Its main objective is the development of serviceable clinical practice guidelines in order to improve the quality of health care and the outcome of cancer patients. The methodology is based on a literature review, followed by a critical appraisal by a multidisciplinary group of experts. Draft guidelines are produced, then validated by specialists in cancer care delivery. OBJECTIVES: Produce clinical practice guidelines for the brachytherapy of prostate cancer using the methodology developed by the Standards, Options and Recommendations project. METHODS: The FNCLCC and the French Urology Association (AFU) first designated the multidisciplinary group of experts. Available data were collected by a search of Medline and lists selected by experts in the group. A first draft of the guidelines was written, they validated by independent reviewers. RESULTS: The main recommendations are: 1/Brachytherapy with permanent seeds alone is a possible curative treatment for prostate cancer patients with the following prognosis factors: tumour stage T1 or T2a (TNM 1992), Gleason score < or = 6 and PSA < 10 micrograms/L. 2/Combined treatment with brachytherapy and hormonal therapy could be more efficient than brachytherapy alone for prostate cancer patients with Gleason score > 7 and/or PSA > 10.3/Combination of brachytherapy and external beam radiation therapy can be proposed to prostate cancer patients with intermediate prognosis. 4/Before and after seed implantation, risks of infection must be prevented by appropriate antibiotic therapy (recommendation). 5/Brachytherapy must not be performed within 2 months of transurethral prostate resection. 6/The height of the urethra receiving more than 200% of the prescribed dose must be reported. The portion of the rectum receiving 100 and 120% of the prescribed dose must be limited to 10 and 5 mm length, respectively.

Influence of scanning doses of iodine-131 on subsequent first ablative treatment outcome in patients operated on for differentiated thyroid carcinoma.

UNLABELLED: The therapeutic outcome after (131)I first ablative treatment in patients operated on for nonmedullary differentiated thyroid carcinoma was compared after both the currently used scanning dose of 111 MBq (131)I and a scanning dose of 37 MBq (131)I. METHODS: Two-hundred twenty-nine consecutive patients with no known metastases were retrospectively studied. They were divided in two populations according to the scanning dose (127 patients with 111 MBq and 102 patients with 37 MBq). All patients received 111 or 37 MBq (131)I for diagnostic purposes and 3.7 GBq (131)I for ablative therapy 9 days later. To assess the efficacy of the treatment, all patients were studied with (131)I and with thyroglobulin plasma assays 6-17 mo later. RESULTS: Successful outcome was significantly more frequent after a scanning dose of 37 MBq (131)I than after a scanning dose of 111 MBq (76% versus 50%, p < 0.001). The treatment efficacy was particularly enhanced after 37 MBq in patients with associated lymphocytic thyroiditis. CONCLUSION: In patients with no known metastases, our data suggest that the impairment of the treatment efficacy observed after a scanning dose of 111 MBq (131)I is related to a stunning effect on the thyroid remnants. The threshold amount above which this effect begins to occur in thyroid remnants could be between 37 and 111 MBq (131)I. Consequently, a scanning dose of only 37 MBq (131)I could be recommended before first ablative treatment. The absence of metastatic patients in our study prevents any conclusion about the possible stunning of the neoplastic tissue. Nevertheless, we must suspect such an effect and try to avoid it, especially during follow-up after first radioiodine therapy. For instance, one may consider postponing radioiodine treatment several weeks or even months after scanning dose administration or using only thyroglobulin measurement for patients who are likely to receive a subsequent radioiodine treatment.

[Positron emission tomography (PET) and (F-18)-fluorodeoxyglucose in (FDG) in cancerology]. / Tomographie par émission de positons (TEP) et [F-18]-fluorodésoxyglucose (FDG) en cancérologie.

Positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) is a scintigraphic imaging technique undergoing a rapid growth in the field of oncology. The constant progress of the detectors, either CDET or PET dedicated cameras, allows to obtain in routine conditions images with a 5 mm spatial resolution. Absolute tracer uptake quantification is also possible, which allows to evaluate objectively therapy efficacy. The mechanisms of FDG tissular accumulation are now better understood. Increase of glycolysis and of transmembrane transport of glucose seems to be at the origin of the high tumorous accumulation of FDG. The main current oncologic application of FDG PET is the diagnosis of malignancy of the isolated pulmonary nodules, with a sensitivity of more than 95%, and in the staging of lung cancer where PET shows higher performances than conventional imaging. The same stands in cutaneous melanoma and for malignancies of the digestive tract, either in colorectal, pancreatic or esophageal localizations. In colorectal cancers, the role of PET has for long being recognized in the differential diagnosis between recurrence and postoperative fibrosis. In the head and neck tumors, FDG also allows to differentiate between recurrence and postradiation necrosis. In lymphoma, the most suitable site for biopsy can be identified on a PET scan and therapy efficacy can also be assessed. In breast cancer, the detection of metastases seems to be possible with FDG. In brain and thyroid cancers, the role of FDG PET remains to be further determined. The low uptake of FDG in prostate cancer metastasis is not in favor of its use in this indication. In conclusion, the indications of FDG PET in oncology are now becoming more precise and it can be expected that clinical PET centers will soon appear in France.

Predicting the efficacy of first iodine-131 treatment in differentiated thyroid carcinoma.

UNLABELLED: The purpose of this study was to search for predictors of (131)I first ablative treatment efficacy in patients with postsurgical remnants after total thyroidectomy for nonmedullary differentiated thyroid carcinoma with no known metastasis. METHODS: Thirty-seven patients were retrospectively studied. None presented antithyroglobulin antibodies. All patients received 111 MBq of (131)I for diagnostic purpose and, 9 days later, 3.7 GBq of (131)I for ablative therapy (IAT). To assess the efficacy of treatment, all patients were studied with (131)I and with thyroglobulin (Tg) plasma assays 6-15 mo later. Treatment was considered successful if no abnormal uptake was seen on whole-body scan and if the Tg plasma level was lower than 1 ng/ml. RESULTS: Ablative treatment was found to be successful in 17 patients [IAT(+)] and unsuccessful in 20 [IAT(-)]. There was no significant difference between the two groups for clinical and histological data, size of thyroid remnants on a 1:1 dot scan and TSH level just before treatment. Although Tg levels were not different in the two groups before scanning dose administration (D0), Tg levels were higher in IAT(-) group 9 days later, just before radioiodine treatment administration (D9) and, in contrast, Tg levels were higher in the IAT(+) group 5 days after treatment administration (D14). Tg percentage change between D9 and D14 was significantly higher in the IAT(+) group and, with an optimal cutoff value of 750%, this parameter would have been able to predict successful treatment in 9 of 10 cases and unsuccessful treatment in 18 of 21 cases. Conversely, Tg percentage change between D0 and D9 was significantly higher in the IAT(-) group and of 11 patients with more than 100% change, 10 belonged to this group. CONCLUSION: The increase in Tg during the first (131)I ablative treatment could be a good predictor of treatment efficacy for patients with nonmetastatic differentiated thyroid carcinoma. Conversely, the increase in Tg observed after the administration of the scanning dose of (131)I just before ablative therapy is associated with a more frequent incomplete ablation, perhaps reflecting a stunning effect on the thyroid remnants.

Highly sensitive immunoradiometric assay for serum thyroglobulin with minimal interference from autoantibodies.

Five monoclonal antibodies (MAbs) directed against antigenic domains on thyroglobulin (Tg) not recognized by most anti-Tg human autoantibodies (aAbs) have been used to develop an improved IRMA for serum Tg with a limit of detection of 0.2 micrograms/L. Samples are incubated for 3 h in tubes coated with four anti-Tg MAbs. After washing, the tubes are incubated with the tracer MAb for 20 h at room temperature. Dilution and reproducibility tests demonstrated assay reliability. Tests performed on samples with (n = 361) or without (n = 283) aAbs showed that the TG IRMA Pasteur is largely independent of the marked interference generally caused by aAbs. These results were confirmed with an extended population of 2759 samples. For a cutoff of 1 micrograms/L, sensitivity and specificity were 0.97 and 1, respectively, in a follow-up of differentiated thyroid carcinoma in patients treated by total thyroidectomy.