Radiation risks : a way to inform patient : 3.10

Purpose: Diagnostic radiology involving ionizing radiation often leads to crucial information but also involves risk. Estimated cancer risks associated with CT range between 1 in 1000 to 1 in 10 000, depending on age and exposure settings. The aim of this contribution is to provide radiologists a way to inform a patient about these risks on a collective and individual base. Materials and methods: After a brief review of the effects of ionizing radiations, conversion from dose indicators into effective dose will be presented for radiography, fluoroscopy and CT. The Diagnostic Reference Level (DRL) concept will be then introduced to enable the reader to compare the level of exposure of various examinations. Finally, the limit of effective dose will be explained and risk projections after various radiological procedures for adults and children will be presented. Results: From an individual standpoint the benefit of a well justified and optimized CT examination clearly outweigh its risk of inducing a fatal cancer. The uncertainties associated with the effective dose concept should be kept in mind in order to avoid cancer risk projections after an examination on an individual basis. Conclusion: Risk factors or effective dose are not the simplest tools to communicate when dealing with radiological risks. Thus, a set of categories should be preferred as proposed in the ICRP (International Commission on Radiation Protection) report 99.

Patient with Fanconi Syndrome (FS) and retinitis pigmentosa (RP) caused by a deletion and duplication of mitochondrial DNA (mtDNA).

BACKGROUND: We report a patient with a highly unusual presentation of a mitochondrial disorder. HISTORY AND SIGNS: An 8-year old girl presented with muscular cramps as well as height and weight deceleration. Investigations revealed lactic acidosis, electrolytic imbalance and urinary loss of glucose and electrolytes secondary to proximal renal tubulopathy consistent with Fanconi syndrome (FS). Ophthalmic examination revealed asymptomatic retinitis pigmentosa (RP) with no other ocular manifestations. A mitochondriopathy was suspected and genetic analysis performed. THERAPY AND OUTCOME: Southern blotting documented a heteroplasmic mutation of mtDNA with deletion/duplication. Three discrete mitochondrial genomes were detected: normal; deletion of 6.7 kb and a deletion/duplication consisting of 1 normal and 1 deleted genome. The relative proportions varied considerably between tissues. CONCLUSIONS: The association of FS and RP combines features of Kearns-Sayre syndrome and Pearson marrow-pancreas syndrome, without being typical of either. This highly unusual clinical presentation emphasises the need for systemic investigation of patients with FS and further underlines the importance of mtDNA analysis in patients with unexpected associations of affected tissues.

Induction of CD8 T-cell responses restricted to multiple HLA class I alleles in a cancer patient by immunization with a 20-mer NY-ESO-1f (NY-ESO-1 91-110) peptide.

Immunogenicity of a long 20-mer NY-ESO-1f peptide vaccine was evaluated in a lung cancer patient TK-f01, immunized with the peptide with Picibanil OK-432 and Montanide ISA-51. We showed that internalization of the peptide was necessary to present CD8 T-cell epitopes on APC, contrasting with the direct presentation of the short epitope. CD8 T-cell responses restricted to all five HLA class I alleles were induced in the patient after the peptide vaccination. Clonal analysis showed that B*35:01 and B*52:01-restricted CD8 T-cell responses were the two dominant responses. The minimal epitopes recognized by A*24:02, B*35:01, B*52:01 and C*12:02-restricted CD8 T-cell clones were defined and peptide/HLA tetramers were produced. NY-ESO-1 91-101 on A*24:02, NY-ESO-1 92-102 on B*35:01, NY-ESO-1 96-104 on B*52:01 and NY-ESO-1 96-104 on C*12:02 were new epitopes first defined in this study. Identification of the A*24:02 epitope is highly relevant for studying the Japanese population because of its high expression frequency (60%). High affinity CD8 T-cells recognizing tumor cells naturally expressing the epitopes and matched HLA were induced at a significant level. The findings suggest the usefulness of a long 20-mer NY-ESO-1f peptide harboring multiple CD8 T-cell epitopes as an NY-ESO-1 vaccine. Characterization of CD8 T-cell responses in immunomonitoring using peptide/HLA tetramers revealed that multiple CD8 T-cell responses comprised the dominant response.

Primary breast lymphoma: patient profile, outcome and prognostic factors. A multicentre Rare Cancer Network study.

BACKGROUND: To asses the clinical profile, treatment outcome and prognostic factors in primary breast lymphoma (PBL). METHODS: Between 1970 and 2000, 84 consecutive patients with PBL were treated in 20 institutions of the Rare Cancer Network. Forty-six patients had Ann Arbor stage IE, 33 stage IIE, 1 stage IIIE, 2 stage IVE and 2 an unknown stage. Twenty-one underwent a mastectomy, 39 conservative surgery and 23 biopsy; 51 received radiotherapy (RT) with (n = 37) or without (n = 14) chemotherapy. Median RT dose was 40 Gy (range 12-55 Gy). RESULTS: Ten (12%) patients progressed locally and 43 (55%) had a systemic relapse. Central nervous system (CNS) was the site of relapse in 12 (14%) cases. The 5-yr overall survival, lymphoma-specific survival, disease-free survival and local control rates were 53%, 59%, 41% and 87% respectively. In the univariate analyses, favorable prognostic factors were early stage, conservative surgery, RT administration and combined modality treatment. Multivariate analysis showed that early stage and the use of RT were favorable prognostic factors. CONCLUSION: The outcome of PBL is fair. Local control is excellent with RT or combined modality treatment but systemic relapses, including that in the CNS, occurs frequently.

Ulnar Nerve Transposition at the Elbow under Local Anesthesia: A Patient Satisfaction Study.

Background Ulnar nerve decompression at the elbow traditionally requires regional or general anesthesia. We wished to assess the feasibility of performing ulnar nerve decompression and transposition at the elbow under local anesthesia. Methods We examined retrospectively the charts of 50 consecutive patients having undergone ulnar nerve entrapment surgery either under general or local anesthesia. Patients were asked to estimate pain on postoperative days 1 and 7 and satisfaction was assessed at 1 year. Results On day 1, pain was comparable among all groups. On day 7, pain scores were twice as high when transposition was performed under general anesthesia when compared with local anesthesia. Patient satisfaction was slightly increased in the local anesthesia group. These patients were significantly more willing to repeat the surgery. Conclusion Ulnar nerve decompression and transposition at the elbow can be performed under local anesthesia without added morbidity when compared with general anesthesia.

Comment explorer une exophtalmie? [How to investigate a patient with exophthalmos?]

Exophthalmos is the main symptom revealing orbital masses. This sign needs to be imaged mainly by MRI and/or CT. As Graves disease is the main etiology of exophthalmos, CT scan should be performed as the initial imaging modality. Indications for US and Doppler are mostly limited to the study of ocular masses, and eventually may help the characterization of extra-ocular lesions. In all cases, imaging is useful to characterize: the precise location of the lesion which can be the intra-conal space (including muscles), the extra-conal space (associated or not to an extra-orbital lesion), or the eyeball; the features of the lesion (density, signal, enhancement.). These findings are used to generate a differential diagnosis. Imaging is also useful to precise the extension of the mass, and in some cases to select the appropriate surgical approach, and for follow-up.

Occupational and patient exposure as well as image quality for full spine examinations with the EOS imaging system.

PURPOSE: EOS (EOS imaging S.A, Paris, France) is an x-ray imaging system that uses slot-scanning technology in order to optimize the trade-off between image quality and dose. The goal of this study was to characterize the EOS system in terms of occupational exposure, organ doses to patients as well as image quality for full spine examinations. METHODS: Occupational exposure was determined by measuring the ambient dose equivalents in the radiological room during a standard full spine examination. The patient dosimetry was performed using anthropomorphic phantoms representing an adolescent and a five-year-old child. The organ doses were measured with thermoluminescent detectors and then used to calculate effective doses. Patient exposure with EOS was then compared to dose levels reported for conventional radiological systems. Image quality was assessed in terms of spatial resolution and different noise contributions to evaluate the detector's performances of the system. The spatial-frequency signal transfer efficiency of the imaging system was quantified by the detective quantum efficiency (DQE). RESULTS: The use of a protective apron when the medical staff or parents have to stand near to the cubicle in the radiological room is recommended. The estimated effective dose to patients undergoing a full spine examination with the EOS system was 290μSv for an adult and 200 μSv for a child. MTF and NPS are nonisotropic, with higher values in the scanning direction; they are in addition energy-dependent, but scanning speed independent. The system was shown to be quantum-limited, with a maximum DQE of 13%. The relevance of the DQE for slot-scanning system has been addressed. CONCLUSIONS: As a summary, the estimated effective dose was 290μSv for an adult; the image quality remains comparable to conventional systems.