Ulrike Garske

High Success Rate of Parathyroid Reoperation may be Achieved with Improved Localization Diagnosis

IntroductionBecause of the difficulty of reoperative parathyroid surgery, preoperative imaging studies have been increasingly adopted. We report the use of consistently applied localization diagnosis to yield high success rates in parathyroid reoperations.MethodsParathyroid reoperation was performed after previous parathyroid surgery in 144 patients with nonmalignant hyperparathyroidism (HPT) between 1962 and 2007. From the year 2000, 46 patients who underwent parathyroid reoperation and 14 patients who were subjected to thyroid surgery before primary parathyroid operation were investigated with sestamibi scintigraphy (MIBI), 11C-methionine PET/CT (met-PET), surgeon-performed ultrasound (US), US-guided fine-needle aspiration biopsy (US-FNA), and selective venous sampling (SVS) with rapid PTH (Q-PTH) analyses. When imaging was considered adequate, additional studies were generally not obtained.ResultsReversal of hypercalcemia was achieved by reoperation in 134 of 144 (93%) of all patients with previous parathyroid surgery. In patients operated from year 2000, MIBI had 90% sensitivity and 88% predictive value, met-PET 79% sensitivity and 87% predictive value, and US 72% sensitivity and 93% predictive value. SVS with Q-PTH analyses provided accurate localization or regionalization in 11 of 11 recently selected patients. Q-PTH analyses in fine-needle aspirations verified parathyroid origin of excised specimens, and intraoperative Q-PTH helped decide when operations could be terminated. In patients subjected to the algorithm of imaging procedures, reversal of hypercalcemia and apparent cure was obtained after the reoperation in 45 of 46 patients with previous parathyroid surgery, implying a success rate of 98%, and in all patients with previous thyroid surgery.ConclusionsReoperative parathyroid surgery is challenging. Results can be improved by consistently applied sensitive methods of preoperative imaging, and reoperative procedures may then achieve nearly the same success rates as primary operations.

Early prediction of response to first-line chemotherapy by sequential [18F]-2-fluoro-2-deoxy-D-glucose positron emission tomography in patients with advanced colorectal cancer

BACKGROUND To evaluate [(18)F]-2-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET), for early evaluation of response to palliative chemotherapy and for prediction of long-term outcome, in patients with metastatic colorectal cancer (mCRC). PATIENTS AND METHODS In a randomized trial, patients with mCRC received irinotecan-based combination chemotherapy. FDG-PET was carried out before treatment and after two cycles in 51 patients at two centers. Visual changes in tumor FDG uptake and changes measured semi-automatically, as standard uptake values (SUVs), were compared with radiological response after four and eight cycles. RESULTS The mean baseline SUV for all tumor lesions per patient was higher in nonresponders than in responders (mean 7.4 versus 5.6, P = 0.02). There was a strong correlation between metabolic response (changes in SUV) and objective response (r = 0.57, P = 0.00001), with a sensitivity of 77% and a specificity of 76%. There was no significant correlation between metabolic response and time to progression (P = 0.5) or overall survival (P = 0.1). CONCLUSIONS Although metabolic response assessed by FDG-PET reflects radiological tumor volume changes, the sensitivity and specificity are too low to support the routine use of PET in mCRC. Furthermore, PET failed to reflect long-term outcome and can, thus, not be used as surrogate end point for hard endpoint benefit.

Lessons on Tumour Response: Imaging during Therapy with 177Lu-DOTA-octreotate. A Case Report on a Patient with a Large Volume of Poorly Differentiated Neuroendocrine Carcinoma

Favourable outcomes of peptide receptor radiotherapy (PRRT) of neuroendocrine tumours have been reported during the last years. Still, there are uncertainties on the radionuclides to be used, the treatment planning, and the indication in patients with a high proliferation rate. This case report describes a patient with a high tumour burden of poorly differentiated neuroendocrine carcinoma of unknown primary with a proliferation rate in liver metastases up to 50%, undergoing fractionated treatment with 7 cycles of 177Lu-DOTA-octreotate (7.4 GBq each) after disease progression on two different chemotherapy regiments. Based on initial staging scintigraphy, somatostatin receptor expression was very high. Longitudinal dosimetry studies during therapy indicated ongoing increases in tumour-to-organ ratios that coincided with an objective response. We conclude that fractionated therapy with 177Lu-DOTA-octreotate should be considered a treatment option also for those patients with large tumours, high proliferation, and high receptor expression.

Minor changes in effective half-life during fractionated 177Lu-Octreotate therapy

Abstract Aims. Fractionated 177Lu-DOTA-octreotate therapy has been reported to be an effective treatment option for patients with generalized neuroendocrine tumors. In our clinic, full individual dosimetry is performed during the first therapy cycle, while dosimetry at later cycles is based on the 24 h uptake measurement assuming an unchanged effective half-life. Our aim was to evaluate this assumption and the variation in the 24 h uptake during therapy. Patients. Thirty patients, 13 women and 17 men, were included in the study. Methods. During the first therapy cycle the 177Lu-concentration was measured with SPECT/CT over the abdomen at 24 h, 96 h and 168 h after infusion. The effective half-life was determined for the kidneys, liver and spleen. The procedure was repeated at cycle 4 or 5. Results. The median ratio between the effective half-lives of the latter and the first cycle was 0.97 and 1.01 for the right and left kidney, with a range of 0.89–1.01 (1st–3rd quartile) and 0.93–1.05, respectively. Discussion. The mean value of the ratios was slightly lower than one, indicating a tendency towards increased activity elimination during therapy. In individual patients, significant changes were found for all organs, often when a large tumor burden reduction occurred during treatment. Possible contributing factors appeared to be larger amounts of non-tumor bound tracer, improved organ function (kidneys), decrease of vessel obstruction (spleen), less scatter from large tumors and reduction of small metastases (liver and spleen). Conclusion. With most patients it is safe to estimate absorbed doses to kidneys, liver and spleen from 24 h activity concentration assuming an unchanged effective half-life during therapy. Patients with risk factors for kidney dysfunction need to be monitored in more detail. Simplified dosimetry based on the assumption of unchanged effective half-life can function as guidance to the number of therapy cycles an individual patient can tolerate.

MP-13.08: Detection of immune responses against urinary bladder cancer in sentinel lymph nodes

Objective: The lymphatic drainage from a tumour is received in the sentinel node where the immune system encounters tumour derived antigens. We investigated anti-tumoural lymphocyte function in sentinel nodes from patients with urinary bladder cancer. Methods: In 14 patients undergoing cystectomy due to bladder cancer, radioactive tracer and blue dye were used to identify the sentinel node. Cell suspensions from the tumour, sentinel- and non-sentinel nodes and peripheral blood were analyzed by flow cytometry with antibodies against lymphocyte surface antigens and against the tumour cell marker cytokeratin-20. Reactivity against autologous tumour extract and the mitogen Concanavalin A was tested in proliferation assays with 3 HThymidine incorporation. Lymphocytes were put in long-term culture with IL-2 and autologous tumour extract. Results: Sentinel nodes were detected in 12 of the 14 patients. Antigen dependent proliferation in response to autologous tumour extract was detected in 6 patients, in 5 cases in sentinel nodes, in the remaining case in a non-sentinel node. Proliferation against Concanavalin A was vigorous in lymph nodes from all patients, whereas tumour infiltrating lymphocytes were unresponsive. Lymphocytes from sentinel nodes could be expanded in vitro. Conclusion: Tumour reactive lymphocytes are present in sentinel nodes draining human bladder cancers. These cells display immunologic

Selective internal radiation therapy in patients with carcinoid liver metastases

letrozole either has no effect or may even increase insulin sensitivity. This difference might be attributed to the steroidal vs the non-steroidal structure of each compound, respectively. Possibly, the androgenic structure of exemestane [7] may be directly responsible for the diabetes-promoting action (independent from its effect on aromatase and estrogen levels), as demonstrated for other androgens. The elucidation of this phenomenon warrants further research.