Intracavitary brachytherapy using stereotactically applied phosphorus-32 colloid for treatment of cystic craniopharyngiomas in 53 patients.

This paper summarizes outcomes of a single-center study of intracavitary brachytherapy (IBT) with stereotactically applied phosphorus-32 ((32)P) colloid for treatment of cystic craniopharyngiomas. We assessed its efficacy and safety, on the basis of clinical and radiological outcomes in one of the largest reported patient series. Between 1992 and 2011, 53 patients were treated with IBT, 14 without previous treatment and 39 who had previously been treated for recurrent cysts. Intervention was performed by applying 200 Gy to the internal cyst wall (median volume 6.1 ml). Median clinical and radiological follow-up were 60.2 and 53.0 months, respectively. Actuarial tumor cyst control was 86.0 ± 5.3 % at 12, 24, and 60 months. Actuarial out-of-field control (development of new cysts or progression of solid tumor parts) was 90.9 ± 4.3, 84.0 ± 5.6, and 54.5 ± 8.8 % after 12, 24, and 60 months, respectively. Corresponding actuarial overall progression-free survival was 79.4 ± 6.1, 72.4 ± 6.8, and 45.6 ± 8.7 % at 12, 24, and 60 months, respectively. Visual function improved for 12 patients (23.5 %), remained unchanged for 34 patients (66.7 %), and worsened for five patients (9.8 %), correlating with tumor progression in each case. Endocrinological deterioration occurred for ten patients (19.6 %); for nine patients this was a result of tumor progression or after tumor resection and for one it was attributed to irradiation. Within six months of IBT seven patients (13.7 %) experienced transient neurological deficits and two patients (3.9 %) deteriorated permanently (hemiparesis and third nerve palsy). Stereotactically applied (32)P is highly efficacious for control of cystic components of craniopharyngiomas and is associated with a low risk of permanent morbidity. The procedure does not, however affect the development of new cysts or the progression of solid tumor parts.

Pentixafor PET/CT for imaging of chemokine receptor 4 expression in esophageal cancer - a first clinical approach.

BACKGROUND: Expression of CXCR4, a chemokine (C-X-C motif) receptor that plays a central role in tumor growth and metastasis of circulating tumor cells, has been described in a variety of solid tumors. A high expression of CXCR4 has a prognostic significance with regard to overall and progression-free survival and offers a starting point for targeted therapies. In this context, [68]Ga-Pentixafor-Positron Emission Tomography/Computer Tomography (PET/CT) offers promising possibility of imaging the CXCR4 expression profile. We set out to compare a [18F] fluorodeoxyglucose (FDG)-PET/CT and a [68Ga]Pentixafor-PET/CT in (re-)staging and radiation planning of patients with localized esophageal cancer. MATERIALS AND METHODS: In this retrospective analysis, ten patients, with adeno- or squamous cell carcinoma of the esophagus (n = 3 and n = 7, respectively), which were scheduled for radio (chemo) therapy, were imaged using both Pentixafor and FDG PET/CT examinations. All lesions were visually rated as Pentixafor and FDG positive or negative. For both tracers, SUVmax was measured all lesions and compared to background. Additionally, immunohistochemistry of CXCR4 was obtained in patients undergoing surgery. RESULTS: FDG-positive tumor-suspicious lesions were detected in all patients and a total of 26 lesions were counted. The lesion-based analysis brought equal status in 14 lesions which were positive for both tracers while five lesions were FDG positive and Pentixafor negative and seven lesions were FDG negative, but Pentixafor positive. Histopathologic correlation was available in seven patients. The CXCR4 expression of four non-pretreated tumour lesion samples was confirmed immunohistochemically. CONCLUSION: Our data shows that additional PET/CT imaging with Pentixafor for imaging the CXCR4 chemokine receptor is feasible but heterogeneous in both newly diagnosed and pretreated recurrent esophageal cancer. In addition, the Pentixafor PET/CT may serve as complementary tool for radiation field expansion in radiooncology.

Treatment of refractory Hodgkin's lymphoma patients with an iodine-131-labeled murine anti-CD30 monoclonal antibody.

PURPOSE: Hodgkin's lymphoma (HL) has been demonstrated to be a good target for immunotherapy since lymphocyte activation markers such as CD30 are expressed in high numbers on the malignant cells. Thus, we developed a new radioimmunoconjugate consisting of the murine anti-CD30 monoclonal antibody (MAb) Ki-4 labeled with iodine-131 ((131)I). PATIENTS AND METHODS: The biodistribution of (131)I-Ki-4 was assessed via dosimetry after preinfusion of 5 mg native Ki-4 followed by 250 to 300 MBq (131)I-labeled Ki-4. Whole-body scintigraphy was performed 1 hour, 24 hours, 48 hours, 72 hours, and 6 days after the infusion. Dosimetry was calculated using the programs NucliDose ICON-IDL (version 5.0.2; Siemens, Erlanger, Germany) and MIRDOSE (version 3.1; Oak Ridge National Laboratories; Oak Ridge, TN). The therapeutic dose was given on day 8 after preinfusion of unlabeled Ki-4. RESULTS: We treated 22 patients with relapsed or refractory CD30-positive HL. Preinfusion of 5 mg native Ki-4 was sufficient to bind the soluble CD30. Imaging demonstrated localization of involved areas measuring 5 cm in diameter or more in four patients and 2.5 cm in one patient. Patients received total body doses of 0.035 Gy to 0.99 Gy. Acute toxicity was mild with grade 1 fatigue in 19 of 22 assessable patients. Seven patients experienced grade 4 degrees hematotoxicity 4 to 8 weeks after treatment. Response included one complete remission, five partial remissions, and three minor responses. CONCLUSION: Treatment with (131)I-Ki-4 is effective but can be associated with severe hematotoxicity.

201Tl, 99mTc-MIBI, 99mTc-tetrofosmin and 99mTc-furifosmin: relative retention and clearance kinetics in retrogradely perfused guinea pig hearts.

Myocellular kinetics of 201Tl, 99mTc-MIBI, 99mTc-tetrofosmin and 99mTc-furifosmin were investigated using retrogradely-perfused guinea-pig hearts. Relative retention decreased in the order 99mTc-MIBI ==> 99mTc-tetrofosmin ==> 99mTc-furifosmin. 201Tl and 99mTc-MIBI exhibited bi- (t1,t2), 99mTc-tetrofosmin and 99mTc-furifosmin triexponential (t1,t2,t3) time-activity-curves. Latest-phase elimination-half-life increased from 201Tl (t2) ==> 99mTc-MIBI (t2) ==> 99mTc-tetrofosmin (t3) ==> 99mTc-furifosmin (t3), showing a significant increase in deteriorating myocardium for all tracers but 99mTc-furifosmin. Delayed elimination in deteriorating myocardium explains at least partly the redistribution phenomenon of 201Tl, and suggests a similar phenomenon for 99mTc-MIBI and 99mTc-tetrofosmin.