P08.02 Israeli experience with Patient Reported Outcomes (PROs) in the field of neuro oncology - Quality of Life Assessment Metrics (QAM)

BACKGROUND

With the development of personalized medicine, it is necessary to take into consideration PROs, including quality of life (QOL) to adjust the treatment and follow up. Trends of QOL outcomes are of special interest for neuro oncologic patients in the setting of chemo-radiotherapy due to the high incidence of pseudo progression (worse MRI with no tumor progression). There are several QAM in the field of neuro oncology. We used the quality of life questionnaire (QLQ-30) for brain cancer with the QLQ-BN20 supplement, and Functional assessment of chronic illness therapy (FACIT) with the FACT-Br supplement (version 4). We looked at the level of agreement between the two assessment tools for QAM for Israeli patients with different brain tumors.

MATERIAL AND METHODS

Forty patients were recruited between September 2017 to May 2018 at Sheba Medical Center after local IRB approval. Patients fulfilled the two types of questionnaires at 4 time points: before radiotherapy, with radiotherapy completion, at three months follow up and before another intervention. The difference between the two metrics was measured by t-test and performed by Bland-Altman plot. The association between QAM and MRI after radiotherapy and doctor assessment was measured by Linear regression.

RESULTS

Forty patients completed 162 questionnaires overall (QLQ-30 and FACIT): 8 patients completed questionnaires at all 4 time points, 7 patients completed questionnaires - 3 times, 6 patients- twice, and 19 patients- once. Three patients didn’t answer FACIT questionnaires and 3 other patients didn’t answer QLQ questionnaires. Patients population included 40% (16/40) with astrocytoma [25% (4/16), 31.2% (5/16), 43.8% (7/16) of them with WHO Grade 2,3,4 respectively], 25% (10/40) with meningioma [60% (6/10), 20% (2/10), and 20% (2/10) of them with WHO Grade 1,2 and 3 respectively], 20% (8/40) with brain metastasis, and other tumors (6/40) consisted 15% of the patient population. We found a significant difference between QAM means of agreement of the two metrics used (p<0.001). There was a significant correlation between QAM and MRI after radiotherapy (p=0.013; R2=0.369 and p=0.025; R2=0.292 for QLQ and FACIT questionnaire, respectively). There was no significant correlation between physician examination and QAM metrics (p=0.880; R2=0.002 and p=0.724; R2=0.009 for QLQ and FACIT questionnaires respectively).

CONCLUSION

Patients’ evaluation success depends on the appropriate assessment metrics. QLQ questionnaires were a more appropriate tool in our patient population confirmed by MRI assessment compared to physicians’ evaluation. Our study shows a significant difference between two well validated tools. Further research is needed to establish the source of this difference and adjust QAM for neuro oncologic patients accordingly.

P14.38 Clinical experience with tumor treating fields (TTFields) treatment for posterior fossa tumors

Introduction: TTFields brought a new concept in the treatment of brain tumors. It was tested and recommended for use in supra-tentorial lesions. There is a paucity of data available about TTFields safety and efficacy for infra-tentorial lesion.

Method: Patients with posterior fossa tumors were treated with the Optune® system. Initial transducer array positioning and all technical characteristic were performed with technical support from Novocure.

Results: Two patients with posterior fossa glial tumors were treated. The first is a 27 years old male with DIPG (without pathological confirmation of the tumor grade) who was treated with Stupp protocol. Treatment with TTFields commenced with TMZ adjuvant phase. The second patient is a 33 years old female with cerebello-pontine astrocytoma WHO grade III, IDH I mutated. This patient was treated with partial resection and Stupp protocol. TTFields treatment was started after completing 12 TMZ adjuvant cycles with measurable stable disease. Duration and compliance of TTFields treatment for first patient is 286 days and 86% and for second patient is 168 days and 93.6%. The skin toxicity is minimal and did not require treatment interruption. There is no other TTFields related toxicity. The MRI evaluation had showed improvement in the first patient and stable disease in the second.

Conclusion: According to our knowledge, this is the first report of clinical experience with TTFields treatment for posterior fossa tumors. In our experience, the treatment is feasible and with equal toxicity to previously reported supra-tentorial lesions. Small patient population and short follow up do not allow efficacy evaluation.

Takeover of host ribosomes by divergent IRES elements

The ribosome is the macromolecular machinery in the host cell for which all viruses have to compete. Early in infection, the viral mRNAs have to compete with the host for both the ribosomes and for the limited pool of eukaryotic initiation factors that are needed to facilitate the recruitment of ribosomes to both viral and cellular mRNAs. To circumvent this competition, certain viruses have evolved to recruit ribosomes to IRESs (internal ribosome entry sites), highly specialized RNA elements that are located at the 5'-end of the viral genomes. Here, we discuss how divergent IRES elements can recruit ribosomes and start protein synthesis with only a minimal set of eukaryotic translation initiation factors, and how this mode of translation initiation aids viral gene amplification during early onset of innate immune responses.

Interinstitutional pathology consultations. A reassessment

We retrospectively determined the clinical impact of 1,000 randomly selected interinstitutional pathology consultations (IPCs). An IPC included all specimens from the patient. IPCs were classified as concordant or discordant with the original diagnosis. Discordant IPCs were classified as having a clinical impact or no impact. Discordant IPCs owing to interpretation differences were subclassified further. The IPCs included 1,522 specimens (1,204 histology, 318 cytology); 923 (92.3%) were concordant, 9 (0.9%) indeterminate, and 68 (6.8%) discordant (clinical impact, 37; no impact, 31). Reasons for discordant IPCs were interpretation differences, 45; additional sectioning, 7; ancillary testing, 1; clerical error, 5; or a combination, 10. Reasons for 26 discordant IPCs with clinical impact owing to interpretation differences were overdiagnosis, 11; tumor subtype change, 4; stage change, 4; underdiagnosis, 3; resection margin status change, 2; undergrading, 1; and understaging with resection margin status change, 1. IPC may identify diagnostic discrepancies that impact management for some patients. The prevalence of a clinical impact of IPC on management varies according to body site. Mandatory IPC does ensure identification of clinically significant diagnostic discrepancies; targeted IPC by body site or specimen type may represent an alternative strategy after further data accumulation. Discordant IPCs may be due to factors other than interpretation difference.

The STAR protein QKI-6 is a translational repressor

The signal transduction and activation of RNA (STAR) family of RNA-binding proteins, whose members are evolutionarily conserved from yeast to humans, are important for a number of developmental decisions. For example, in the mouse, quaking proteins (QKI-5, QKI-6, and QKI-7) are essential for embryogenesis and myelination, whereas a closely related protein in Caenorhabditis elegans, germline defective-1 (GLD-1), is necessary for germ-line development. Recently, GLD-1 was found to be a translational repressor that acts through regulatory elements, called TGEs (for tra-2 and GLI elements), present in the 3' untranslated region of the sex-determining gene tra-2. This gene promotes female development, and repression of tra-2 translation by TGEs is necessary for the male cell fates. The finding that GLD-1 inhibits tra-2 translation raises the possibility that other STAR family members act by a similar mechanism to control gene activity. Here we demonstrate, both in vitro and in vivo, that QKI-6 functions in the same manner as GLD-1 and can specifically bind to TGEs to repress translation of reporter constructs containing TGEs. In addition, expression of QKI-6 in C. elegans wild-type hermaphrodites or in hermaphrodites that are partially masculinized by a loss-of-function mutation in the sex-determining gene tra-3 results in masculinization of somatic tissues, consistent with QKI-6 repressing the activity of tra-2. These results strongly suggest that QKI-6 may control gene activity by operating through TGEs to regulate translation. In addition, our data support the hypothesis that other STAR family members may also be TGE-dependent translational regulators.

The STAR protein, GLD-1, is a translational regulator of sexual identity in Caenorhabditis elegans

The Caenorhabditis elegans sex determination gene, tra-2, is translationally regulated by elements in the 3'-untranslated region called TGEs. TGEs govern the translation of mRNAs in both invertebrates and vertebrates, indicating that this is a highly conserved mechanism for controlling gene activity. A factor called DRF, found in worm extracts binds the TGEs and may be a repressor of translation. Using the yeast three-hybrid screen and RNA gel shift analysis, we have found that the protein GLD-1, a germline-specific protein and a member of the STAR family of RNA-binding proteins, specifically binds to the TGEs. GLD-1 is essential for oogenesis, and is also necessary for spermatogenesis and inhibition of germ cell proliferation. Several lines of evidence demonstrate that GLD-1 is a translational repressor acting through the TGEs to repress tra-2 translation. GLD-1 can repress the translation of reporter RNAs via the TGEs both in vitro and in vivo, and is required to maintain low TRA-2A protein levels in the germline. Genetic analysis indicates that GLD-1 acts upstream of the TGE control. Finally, we show that endogenous GLD-1 is a component of DRF. The conservation of the TGE control and the STAR family suggests that at least a subset of STAR proteins may work through the TGEs to control translation.

Conservation of the C.elegans tra-2 3'UTR translational control

The Caenorhabditis elegans sex-determination gene, tra-2, is translationally regulated by two 28 nt elements (DREs) located in the 3'UTR that bind a factor called DRF. This regulation requires the laf-1 gene activity. We demonstrate that the nematode Caenorhabditis briggsae tra-2 gene and the human oncogene GLI are translationally regulated by elements that are functionally equivalent to DREs. Here, we rename the DREs to TGEs (tra-2 and GLI elements). Similarly to the C.elegans tra-2 TGEs, the C.briggsae tra-2 and GLI TGEs repress translation of a reporter transgene in a laf-1 dependent manner. Furthermore, they regulate poly(A) tail length and bind DRF. We also find that the C.elegans TGEs control translation and poly(A) tail length in C.briggsae and rodent cells. Moreover, these same organisms contain a factor that specifically associates with the C.elegans TGEs. These findings are consistent with the TGE control being present in C.briggsae and rodent cells. Three lines of evidence indicate that C.briggsae tra-2 and GLI are translationally controlled in vivo by TGEs. First, like C.elegans tra-2 TGEs, the C.briggsae tra-2 and GLI TGEs control translation and poly(A) tail lengths in C.briggsae and rodent cells, respectively. Second, the same factor in C.briggsae and mammalian cells that binds to the C.elegans tra-2 TGEs binds the C.briggsae tra-2 and GLI TGEs. Third, deletion of the GLI TGE increases GLI's ability to transform cells. These findings suggest that TGE control is conserved and regulates the expression of other mRNAs.