Connectomic Basis for Tremor Control in Stereotactic Radiosurgical Thalamotomy.

BACKGROUND AND PURPOSE: Given the increased use of stereotactic radiosurgical thalamotomy and other ablative therapies for tremor, new biomarkers are needed to improve outcomes. Using resting-state fMRI and MR tractography, we hypothesized that a "connectome fingerprint" can predict tremor outcomes and potentially serve as a targeting biomarker for stereotactic radiosurgical thalamotomy. MATERIALS AND METHODS: We evaluated 27 patients who underwent unilateral stereotactic radiosurgical thalamotomy for essential tremor or tremor-predominant Parkinson disease. Percentage postoperative improvement in the contralateral limb Fahn-Tolosa-Marin Clinical Tremor Rating Scale (TRS) was the primary end point. Connectome-style resting-state fMRI and MR tractography were performed before stereotactic radiosurgery. Using the final lesion volume as a seed, "connectivity fingerprints" representing ideal connectivity maps were generated as whole-brain R-maps using a voxelwise nonparametric Spearman correlation. A leave-one-out cross-validation was performed using the generated R-maps. RESULTS: The mean improvement in the contralateral tremor score was 55.1% (SD, 38.9%) at a mean follow-up of 10.0 (SD, 5.0) months. Structural connectivity correlated with contralateral TRS improvement (r = 0.52; P = .006) and explained 27.0% of the variance in outcome. Functional connectivity correlated with contralateral TRS improvement (r = 0.50; P = .008) and explained 25.0% of the variance in outcome. Nodes most correlated with tremor improvement corresponded to areas of known network dysfunction in tremor, including the cerebello-thalamo-cortical pathway and the primary and extrastriate visual cortices. CONCLUSIONS: Stereotactic radiosurgical targets with a distinct connectivity profile predict improvement in tremor after treatment. Such connectomic fingerprints show promise for developing patient-specific biomarkers to guide therapy with stereotactic radiosurgical thalamotomy.

An update of lanreotide acetate for treatment of adults with carcinoid syndrome.

Carcinoid tumors are rare and usually slow-growing. Some patients with advanced metastatic disease however can develop symptoms of carcinoid syndrome, which results in debilitating diarrhea and flushing. Many treatments including chemotherapy were tried unsuccessfully in the past to treat this syndrome. The symptoms of carcinoid syndrome are thought to be related to the ability of the tumors to produce serotonin. The discovery that the production of this hormone can be inhibited by somatostatin led to the development of somatostatin analogues octreotide and lanreotide, which differ from native somatostatin in that they have a longer half-life. These compounds have shown dramatic responses in symptom control and reduction of serotonin metabolites including urinary 5-hydroxyindoleacetic acid (5-HIAA) levels. This review researches the origins of carcinoid tumors, the development of lanreotide as a treatment and future directions for the treatment of carcinoid syndrome.

Olaratumab for the treatment of soft tissue sarcoma.

Soft tissue sarcoma represents about 1% of all solid malignancies. The standard chemotherapy regimens have included doxorubicin alone or in combination with other agents. Despite recent advances in treatment beyond first line - with the FDA approval of pazopanib, eribulin and trabectidin - overall survival for patients with metastatic disease remains in the region of 12-19 months. Olaratumab is a monoclonal antibody directed against platelet-derived growth factor receptor alpha (PDGFRalpha). It was studied in a phase Ib and randomized phase II study in combination with doxorubicin in patients with soft tissue sarcoma who previously had not received doxorubicin for metastatic disease. The results of the phase II study showed a statistically significant improvement in progression-free survival up to 6 months, and a more dramatic improvement in overall survival to 26.9 months. This is the first randomized trial to show a significant improvement in overall survival compared to doxorubicin alone. An ongoing phase III study has completed accrual and results are being analyzed. Olaratumab has been granted accelerated approval by the United States Food and Drug Administration. Ongoing trials are underway to further demonstrate the mechanism of action. This review will document the studies involved in the development of olaratumab in the treatment of soft tissue sarcomas.

Lexical factors and cerebral regions influencing verbal fluency performance in MCI.

OBJECTIVE: To evaluate assumptions regarding semantic (noun), verb, and letter fluency in mild cognitive impairment (MCI) and Alzheimer disease (AD) using novel techniques for measuring word similarity in fluency lists and a region of interest (ROI) analysis of gray matter correlates. METHOD: Fifty-eight individuals with normal cognition (NC, n=25), MCI (n=23), or AD (n=10) underwent neuropsychological tests, including 10 verbal fluency tasks (three letter tasks [F, A, S], six noun categories [animals, water creatures, fruits and vegetables, tools, vehicles, boats], and verbs). All pairs of words generated by each participant on each task were compared in terms of semantic (meaning), orthographic (spelling), and phonemic (pronunciation) similarity. We used mixed-effects logistic regression to determine which lexical factors were predictive of word adjacency within the lists. Associations between each fluency raw score and gray matter volumes in sixteen ROIs were identified by means of multiple linear regression. We evaluated causal models for both types of analyses to specify the contributions of diagnosis and various mediator variables to the outcomes of word adjacency and fluency raw score. RESULTS: Semantic similarity between words emerged as the strongest predictor of word adjacency for all fluency tasks, including the letter fluency tasks. Semantic similarity mediated the effect of cognitive impairment on word adjacency only for three fluency tasks employing a biological cue. Orthographic similarity was predictive of word adjacency for the A and S tasks, while phonemic similarity was predictive only for the S task and one semantic task (vehicles). The ROI analysis revealed different patterns of correlations among the various fluency tasks, with the most common associations in the right lower temporal and bilateral dorsal frontal regions. Following correction with gray matter volumes from the opposite hemisphere, significant associations persisted for animals, vehicles, and a composite nouns score in the left inferior frontal gyrus, but for letter A, letter S, and a composite FAS score in the right inferior frontal gyrus. These regressions also revealed a lateralized association of the left subcortical nuclei with all letter fluency scores and fruits and vegetables fluency, and an association of the right lower temporal ROI with letter A, FAS, and verb fluency. Gray matter volume in several bihemispheric ROIs (left dorsal frontal, right lower temporal, right occipital, and bilateral mesial temporal) mediated the relationship between cognitive impairment and fluency for fruits and vegetables. Gray matter volume in the right lower temporal ROI mediated the relationship between cognitive impairment and five fluency raw scores (animals, fruits and vegetables, tools, verbs, and the composite nouns score). CONCLUSION: Semantic memory exerts the strongest influence on word adjacency in letter fluency as well as semantic verbal fluency tasks. Orthography is a stronger influence than pronunciation. All types of fluency task raw scores (letter, noun, and verb) correlate with cerebral regions known to support verbal or nonverbal semantic memory. The findings emphasize the contribution of right hemisphere regions to fluency task performance, particularly for verb and letter fluency. The relationship between diagnosis and semantic fluency performance is mediated by semantic similarity of words and by gray matter volume in the right lower temporal region.

Efficacy and tolerability of pharmacotherapy options for the treatment of medullary thyroid cancer.

Metastatic and unresectable medullary thyroid carcinoma (MTC) is often difficult to treat as it is relatively unresponsive to radiation and conventional chemotherapy. This emphasizes the importance of the development of targeted therapies for advanced MTC. Vandetanib was approved by the US Food and Drug Administration for the treatment of symptomatic or progressive MTC in patients with advanced disease in April 2011. This therapy proved to be a breakthrough in the management of MTC. We review the efficacy and safety of this novel treatment and other treatments that are being evaluated in this disease.

Anticipation in familial plasma cell dyscrasias.

Familial myeloma was described as early as 1925; however, the causative factors are unknown. Studies of families with other familial haematological malignancies demonstrate anticipation. Five new families are described in which plasma cell dyscrasias occurred in parent and child generations (six such pairs), and data were pooled with those of 16 other families (with 20 parent-child pairs affected) recorded in the literature. Disease-free survival for parent and child generations were each estimated and differences in the disease-free survival between generations were tested by the log-rank and signed rank methods. In all six previously unreported parent-child pairs with plasma cell dyscrasia and in 18/20 such pairs found in the literature, the disease occurred at an earlier age in the child generation. The median age of onset of myeloma in the parent and child generations of all 26 pairs was 71 years (95% CI 67-78 years) and 50 years (95% CI 45-55 years), respectively (P<0.0001). The ages of onset of malignant plasma cell dyscrasias in the parent and child generations of these families compared with patients in the general population were significantly different for the child generation (P<0.005) but not for the parent generation. It would appear that anticipation occurs in familial myeloma.

Study of Circle of Willis in 1021 consecutive autopsies: incidence of aneurysms, anatomical variations and atherosclerosis.

Incidence of subarachnoid haemorrhage from aneurysmal rupture is very low in India when compared with that in the Western world and Japan. Either they are not recognised or diagnosed adequately or there may be a true decreased geographical/racial incidence. To have an idea of the true incidence of aneurysms, a study of Circle of Willis with its anatomical variations and incidence of atherosclerosis was carried out in 1021 consecutive autopsies. The incidence of anatomical variations was slightly less than that seen in most of the other studies. Atherosclerosis was seen in 9.2% of the Circles of Willis. There were only two aneurysms, both located at the bifurcation of middle cerebral artery. This incidence of 0.2% is definitely much lower than that seen in other series, thus, suggesting that the incidence of subarachnoid haemorrhage from aneurysmal rupture is likely to be genuinely less in India.

Keratinolysis by Absidia cylindrospora and Rhizomucor pusillus: biochemical proof.

Absidia cylindrospora and Rhizomucor pusillus causal agents of phycomycoses, were cultured on sterile natural keratins in a mineral solution and the keratin degradation products analyzed. The excess of sulphur was removed by oxidation to inorganic sulphate and thiosulphate, which were the main products of sulphitolysis of keratin. The proteolytic activity of the two fungi depended on the nature of the keratin substrate. Human scalp hair was the most favoured keratin substrate by both the fungi.