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e17025 Background: PSMA-targeted radioligand therapy (PRLT) using the alpha-emitter Ac-225 PSMA-617 is effective in metastatic prostate cancer progressing after beta-emitter-based PRLT using Lu-177 PSMA-617, and in the presence of diffuse bone marrow metastases. Xerostomia is a dose-limiting factor in PRLT using Ac-225. Augmented Alpha-Beta PRLT is a concept of concomitantly administering Lu-177 and Ac-225 PSMA in lower activities, as a trade-off between efficacy and the dose-limiting toxicity, i.e., xerostomia. The objective of this study was to compare overall survival (OS), progression-free survival (PFS), and incidence of xerostomia among metastatic prostate cancer patients who received Ac-225 PSMA-617 augmentation in the initial phase of Lu-177 PSMA-617 RLT compared to those who received it in the late phase. Initial phase is defined as first two cycles of PSMA radioligand therapy (PRLT) vs late phase as after two cycles. We also examined prognostic factors associated with OS and PFS. Methods: Kaplan Meier method was used to examine survival curves and log-rank tests were conducted to examine differences in survival by groups. Cox Proportional Hazard (CPH) model was used to examine the impact of bone marrow and visceral metastasis and age on OS and PFS. Progression was defined as an increase of ≥ 25% in prostate-specific antigen (PSA) levels. Results: 68 patients who received Ac-225 PSMA-617 by itself, or Ac-225 PSMA-617 augmentation to Lu-PSMA-617 were included in the analysis. Out of these, 15 received early augmentation, 50 received late augmentation, and 3 received Ac-225 PSMA-617 alone. Of these, 48 experienced cancer progression and 21 died due to cancer progression. Median OS was 47 months and PFS was 11 months. Those who received early augmentation had significantly better PFS (median PFS not reached during study period) compared to those who received late augmentation (median PFS: 9 months) (p = 0.02). Early augmentation was associated with lower likelihood of xerostomia (p = 0.09). CPH model suggested that visceral or bone marrow metastasis were associated with significantly worse prognosis for PFS (p = 0.04). Conclusions: In patients progressing after Lu-177 PSMA radioligand therapy and those with diffuse bone-marrow metastases, an earlier augmentation with Ac-225 PSMA-617 is associated with better PFS and lower side effects such as xerostomia. Having visceral or bone marrow metastasis is a poor prognostic indicator for PFS in augmented alpha-beta PSMA radioligand therapy.

Enterprise Search is a continuously evolving and important field, which is seeing a resurgence driven by artificial intelligence. Still, there is no objective, generally accepted way to compare various enterprise search systems. SQuAD is becoming popular for measuring algorithmic reading comprehension (MRC) but is ineffective for quantifying effectiveness of enterprise search in business-use situations. In this paper we modify the SQuAD scoring methodology to propose a scoring system for enterprise search systems that aligns with the real world expectations of users. Further, we use a search system based on Calibrated Quantum Mesh (CQM) to underscore the relevance of this metric.

This paper describes the architecture of a Machine Translation System with source language as English and target language as Marathi. The basic approach used for the development of this system is Rule Based Machine Translation. The basic algorithm for obtaining the correct word order in the target language was developed based on specific traversals of the parse tree. One of the special features of the system is a Word Sense Disambiguation model. Presently only prepositions will be disambiguated and work is going on for verbs and nouns. The model is a generalized approach based on the categories/domains a word belongs to. Another feature is the target language generation module. The focus is on the grammar structure of the target language that will produce better and smoother translations. The architecture though developed specifically for English – Marathi language pair, may be extended to other language pairs with similar structure. The architecture is partially implemented in the form of Machine Translation system. A lexicon is built for morphological and semantic properties. The results, even at partial implementation stage, are really encouraging.

Somatostatin receptors (SSTR) are known for an overexpression in gastroenteropancreatic neuroendocrine tumours (GEP-NET). The aim of the present study was to find out if the receptor density predicted by the semi-quantitative parameters generated from the static positron emission tomography (PET/CT) correlated with the in vitro immunohistochemistry using a novel rabbit monoclonal anti-SSTR2A antibody (clone UMB-1) for specific SSTR2A immunohistochemistry and polyclonal antibodies for SSTR1 and 3-5.Overall 14 surgical specimens generated from 34 histologically documented GEP-NET patients were correlated with the preoperative (68)Ga-DOTA-NOC PET/CT. Quantitative assessment of the receptor density was done using the immunoreactive score (IRS) of Remmele and Stegner; the additional 4-point IRS classification for immunohistochemistry and standardized uptake values (SUV(max) and SUV(mean)) were used for PET/CT.The IRS for SSTR2A and SSTR5 correlated highly significant with the SUV(max) on the PET/CT (p0.001; p0.05) and the IRS for SSTR2A with the SUV(mean) (p0.013). The level of SSTR2A score correlated significantly with chromogranin A staining and indirectly to the tumour grading.The highly significant correlation between SSTR2A and SSTR5 and the SUV(max) on the (68)Ga-DOTA-NOC PET/CT scans is concordant with the affinity profile of (68)Ga-DOTA-NOC to the SSTR subtypes and demonstrates the excellent qualification of somatostatin analogues in the diagnostics of NET. This study correlating somatostatin receptor imaging using (68)Ga-DOTA-NOC PET/CT with immunohistochemically analysed SSTR also underlines the approval of therapy using somatostatin analogues, follow-up imaging as well as radionuclide therapy.

Figure S1. Representative chromatograms of (a) 152Tb-PSMA-617 and (b) 177Lu-PSMA-617 after successful radiolabeling. Table S1. Stability of 152Tb-PSMA-617. (DOCX 517 kb)

Figure S1. Representative chromatograms of (a) 152Tb-PSMA-617 and (b) 177Lu-PSMA-617 after successful radiolabeling. Table S1. Stability of 152Tb-PSMA-617. (DOCX 517 kb)