A phase I/II trial of iodine-131-tositumomab (anti-CD20), etoposide, cyclophosphamide, and autologous stem cell transplantation for relapsed B-cell lymphomas.

Relapsed B-cell lymphomas are incurable with conventional chemotherapy and radiation therapy, although a fraction of patients can be cured with high-dose chemoradiotherapy and autologous stem-cell transplantation (ASCT). We conducted a phase I/II trial to estimate the maximum tolerated dose (MTD) of iodine 131 ((131)I)-tositumomab (anti-CD20 antibody) that could be combined with etoposide and cyclophosphamide followed by ASCT in patients with relapsed B-cell lymphomas. Fifty-two patients received a trace-labeled infusion of 1.7 mg/kg (131)I-tositumomab (185-370 MBq) followed by serial quantitative gamma-camera imaging and estimation of absorbed doses of radiation to tumor sites and normal organs. Ten days later, patients received a therapeutic infusion of 1.7 mg/kg tositumomab labeled with an amount of (131)I calculated to deliver the target dose of radiation (20-27 Gy) to critical normal organs (liver, kidneys, and lungs). Patients were maintained in radiation isolation until their total-body radioactivity was less than 0.07 mSv/h at 1 m. They were then given etoposide and cyclophosphamide followed by ASCT. The MTD of (131)I-tositumomab that could be safely combined with 60 mg/kg etoposide and 100 mg/kg cyclophosphamide delivered 25 Gy to critical normal organs. The estimated overall survival (OS) and progression-free survival (PFS) of all treated patients at 2 years was 83% and 68%, respectively. These findings compare favorably with those in a nonrandomized control group of patients who underwent transplantation, external-beam total-body irradiation, and etoposide and cyclophosphamide therapy during the same period (OS of 53% and PFS of 36% at 2 years), even after adjustment for confounding variables in a multivariable analysis.

Stent marker materials for computerized tomograph-assisted implant planning.

This article analyzes different materials incorporated as markers in stents worn by patients undergoing a multiplanar reformatted computerized tomography (MRCT) study of the dental arch for implant placement planning. Forty-five patients were scanned with marked stents. The type of material used for stent markers was evaluated for visibility; ease of analysis in relation to the alveolar ridge crest and adjacent teeth, other markers, or restorations; and relative to its applicability as a presurgical guide. The advantages or disadvantages of each type of marker were discussed. The clinician should be aware of the variety of marker materials available and of the advantages and disadvantages associated with each to optimize the use of the multiplanar reformatted computerized tomography in implant placement planning.

Comparison of initial lymphoma staging using computed tomography (CT) and magnetic resonance (MR) imaging.

While MR is known to be superior to other imaging methods for detecting marrow involvement by lymphoma, MR is also capable of detecting abnormal lymph nodes. Our objective was to determine whether MR employing short TI inversion recovery (STIR) was comparable to CT in the initial staging of 23 patients with Hodgkin's disease (12 patients) and non-Hodgkin's lymphoma (11 patients). MR images of chest, abdomen, pelvis, and femoral marrow were obtained using the STIR and T1-weighted spin-echo (T1-SE) techniques, employing a protocol initially designed for marrow assessment. In all cases, CT-detected adenopathy was also found by MR. Four patients had marrow involvement by MR, undetected by CT. We conclude that MR and CT may be equivalent imaging modalities in the detection of nodal involvement, and that MR has an advantage in its ability to diagnose marrow involvement. Given the high frequency of focal marrow abnormalities detected by MR in patients with Hodgkin's disease and high-grade non-Hodgkin's lymphoma, MR may be the preferred staging modality for these patients.