[Double vision and a wrong track]. / Doppelbilder und eine falsche Fährte.

A 72-year-old woman presented to our emergency centre with acute horizontal diplopia. Neurological examination revealed an isolated abducens nerve paresis on the left. Hilar enlargement seen on the chest x-ray and an elevated serum ACE level led us to suspect sarcoidosis, but the patient declined further evaluation. In the following days, her visual acuity decreased steadily, and she developed cervicothoracic pain, left sided ptosis, weakness of the right arm, and general asthenia. When she was readmitted as an emergency case, neurological examination revealed decreased visual acuity, external ophthalmoplegia and ptosis on the left and a C8 radicular lesion on the right. Imaging studies showed multilocular lesions, e. g. in the left orbital space, spinal epidural manifestations and lymphoma nodular involvement, including retroperitoneally. Laboratory chemistry showed elevated serum levels of ACE, sIL2 receptor and an elevated CD4 / CD8 ratio while bronchoalveolar lavage indicated lymphocytic alveolitis. The biopsy performed under the left M. masseter with a presumptive diagnosis of sarcoidosis, showed a diffuse large-cell B-cell lymphoma. We initiated immuno-chemotherapy following the R-CHOP schema with a curative approach. The case shows the lack of specificity of clinical, imaging and laboratory findings and thus underlines the need for histology in the differential diagnosis of sarcoidosis.

Impact of rs12917 MGMT Polymorphism on [18F]FDG-PET Response in Pediatric Hodgkin Lymphoma (PHL).

PURPOSE: The enzyme O6-methylguanine-DNA methyltransferase (MGMT) is an important component of the DNA repair machinery. MGMT removes O6-methylguanine from the DNA by transferring the methyl group to a cysteine residue in its active site. Recently, we detected the single nucleotide polymorphism (SNP) rs12917 (C/T) in the MGMT sequence adjacent to the active site in Hodgkin lymphoma (HL) cell line KM-H2. We now investigated whether this SNP is also present in other HL cell lines and patient samples. Furthermore, we asked whether this SNP might have an impact on metabolic response in 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography ([18F]FDG-PET), and on overall treatment outcome based on follow-up intervals of at least 34 months. PROCEDURES: We determined the frequency of this MGMT polymorphism in 5 HL cell lines and in 29 pediatric HL (PHL) patients. The patient cohort included 17 female and 12 male patients aged between 4 and 18 years. After characterization of the sequence, we tested a possible association between rs12917 and age, gender, Ann Arbor stage, treatment group, metabolic response following two courses of OEPA (vincristine, etoposide, prednisone, and doxorubicin) chemotherapy, radiotherapy indication, and relapse status. RESULTS: We detected the minor T allele in four of five HL cell lines. 11/29 patients carried the minor T allele whereas 18/29 patients showed homozygosity for the major C allele. Interestingly, we observed significantly better metabolic response in PHL patients carrying the rs12917 C allele resulting in a lower frequency of radiotherapy indication. CONCLUSION: MGMT polymorphism rs12917 seems to affect chemotherapy response in PHL. The prognostic value of this polymorphism should be investigated in a larger patient cohort.