Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 273
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Br J Haematol ; 200(4): 429-439, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36323643

RESUMEN

Management of acquired immunodeficiency syndrome (AIDS)-related diffuse large B-cell (DLBCL) and plasmablastic lymphomas (PBL) poses significant challenges. The evidence supports use of dose-adjusted EPOCH (etoposide, prednisone, vincristine, cyclophosphamide and doxorubicin) with or without rituximab as first-line therapy. The need for central venous access, growth factors and significant toxicities limits its use in resource-constrained settings. To address these challenges, we have developed a novel regimen, CVEP (cyclophosphamide, vinblastine, etoposide, and prednisolone) based on the pharmacodynamic principles of dose-adjusted EPOCH. This single-centre phase II study evaluated the efficacy and safety of CVEP regimen in patients with de novo systemic AIDS-related DLBCL and PBL. The primary objective was complete response (CR) rates as assessed by positron emission tomography-computed tomography. The secondary objectives were incidence of Grade 3/4 toxicities, toxicities requiring hospitalisation, and disease-free survival. From May 2011 to February 2017, 42 patients were enrolled. At the end of therapy the CR rates were 69% (29/42) in the intention-to-treat population and 80.5% (29/36) in evaluable patients. At a median follow-up of 69 months, the 5-year disease-free survival was 65.3%. Out of 217 cycles administered, febrile neutropenia occurred in 19.3% and hospitalisation was required in 18.3% of cycles. There were two treatment-related deaths. The CVEP regimen is an active and safe regimen for AIDS-related DLBCL and PBL.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Linfoma de Células B Grandes Difuso , Humanos , Etopósido/efectos adversos , Vinblastina/efectos adversos , Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Prednisolona/efectos adversos , Ciclofosfamida/efectos adversos , Prednisona/uso terapéutico , Vincristina/efectos adversos , Doxorrubicina/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos
2.
J Pediatr Hematol Oncol ; 45(3): e363-e369, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36251857

RESUMEN

BACKGROUND: Persisting residual masses at treatment completion are known in rhabdomyosarcoma (RMS) treated with definitive radiotherapy (RT) to the primary site, but their prognostic significance is uncertain. Tumor response as assessed by anatomic imaging is not prognostic and studies based on 18 F-FDG-PET response are limited. We report the prognostic significance of persistent FDG-avidity in residual masses, assessed 3-month postdefinitive RT, in pediatric RMS. MATERIALS AND METHODS: Children 15 years old or below with Group III/IV RMS who received only definitive radiotherapy for local control from June 2013 to December 2018, and had 18 F-FDG-PET CT at 3 months post-RT were retrospectively analyzed for outcomes and other prognostic factors. RESULTS: Sixty-three children were eligible (Group III-55, Group IV-8). 18 F-FDG-PET CT scan done 3 months postradiotherapy showed FDG-avid residual masses in 10 patients (15.9%), anatomic residual in 24 (38.1%), and no anatomic/FDG-avid residual in 29(46.0%). At a median follow-up of 38 months (interquartile range, 24 to 55 mo), 3-year EFS of patients with FDG-avid residual masses was 40.0% (95% CI: 18.7% to 85.5%) versus the rest of the cohort, which was 71.9% (95% CI: 59.8% to 86.5%) ( P =0.008). Three-year OS of patients with FDG-avid residual masses was 50.8% (95% CI: 25.7% to 100.0%) versus the rest of the cohort, which was 77.0% (95% CI: 65.1% to 91.0%) ( P =0.037). Presence of FDG-avid residual disease persisting post-RT affected both EFS [HR-3.34 (95% CI: 1.29 to 8.68) ( P =0.013)] and OS [HR-3.20 (95% CI: 1.01 to 10.12) ( P =0.048)] on univariate analysis and this significance was retained for EFS in multivariate analysis [HR-3.52 (95% CI: 1.33 to 9.30) ( P =0.011)]. CONCLUSIONS: Persistent metabolic activity in residual disease post-chemoradiotherapy in RMS may portend a poorer prognosis with an increased risk of relapse. This subset of high-risk patients needs to be identified, and further trials are warranted to develop strategies to improve their outcomes.


Asunto(s)
Fluorodesoxiglucosa F18 , Rabdomiosarcoma , Humanos , Niño , Adolescente , Estudios Retrospectivos , Recurrencia Local de Neoplasia , Tomografía de Emisión de Positrones/métodos , Pronóstico , Rabdomiosarcoma/diagnóstico por imagen , Rabdomiosarcoma/radioterapia , Tomografía Computarizada por Tomografía de Emisión de Positrones , Radiofármacos
3.
J Digit Imaging ; 36(6): 2519-2531, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37735307

RESUMEN

Lung cancer is the second most fatal disease worldwide. In the last few years, radiomics is being explored to develop prediction models for various clinical endpoints in lung cancer. However, the robustness of radiomic features is under question and has been identified as one of the roadblocks in the implementation of a radiomic-based prediction model in the clinic. Many past studies have suggested identifying the robust radiomic feature to develop a prediction model. In our earlier study, we identified robust radiomic features for prediction model development. The objective of this study was to develop and validate the robust radiomic signatures for predicting 2-year overall survival in non-small cell lung cancer (NSCLC). This retrospective study included a cohort of 300 stage I-IV NSCLC patients. Institutional 200 patients' data were included for training and internal validation and 100 patients' data from The Cancer Image Archive (TCIA) open-source image repository for external validation. Radiomic features were extracted from the CT images of both cohorts. The feature selection was performed using hierarchical clustering, a Chi-squared test, and recursive feature elimination (RFE). In total, six prediction models were developed using random forest (RF-Model-O, RF-Model-B), gradient boosting (GB-Model-O, GB-Model-B), and support vector(SV-Model-O, SV-Model-B) classifiers to predict 2-year overall survival (OS) on original data as well as balanced data. Model validation was performed using 10-fold cross-validation, internal validation, and external validation. Using a multistep feature selection method, the overall top 10 features were chosen. On internal validation, the two random forest models (RF-Model-O, RF-Model-B) displayed the highest accuracy; their scores on the original and balanced datasets were 0.81 and 0.77 respectively. During external validation, both the random forest models' accuracy was 0.68. In our study, robust radiomic features showed promising predictive performance to predict 2-year overall survival in NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Neoplasias Pulmonares/diagnóstico por imagen , Estudios Retrospectivos
4.
Q J Nucl Med Mol Imaging ; 66(2): 162-170, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31496204

RESUMEN

BACKGROUND: Functional imaging such as 18F-fluoro-deoxy-glucose positron emission tomography/computed tomography (FDG-PET/CT), 18F-fluoro-misonidazole (F-MISO)-PET/CT, and diffusion-weighted magnetic resonance imaging (DW-MRI) can assess complex biological phenomena in tumors reflecting underlying disease biology. The aim of this prospective observational study was to correlate quantitative imaging parameters derived from pretreatment biological imaging such as FDG-PET/CT, F-MISO-PET/CT, and DW-MRI with each other and with clinical outcomes in patients with head and neck squamous cell carcinoma (HNSCC) treated with definitive radio(chemo)therapy. METHODS: Twenty patients with pharyngo-laryngeal cancers underwent pretreatment biological imaging. Gross tumor volume (GTV) was delineated on axial planning CT (GTVCT). Quantitative FDG-PET/CT parameters included maximum, mean, minimum standardized uptake values (SUVmax-FDG, SUVmean-FDG, SUVmin-FDG); metabolic tumor volume (MTV); and total lesion glycolysis (TLG). F-MISO-PET/CT parameters included hypoxic tumor volume (HTV); maximum, mean, minimum SUV; and fractional hypoxic volume (FHV). Mean apparent diffusion coefficient (ADCmean) was derived from DW-MRI. RESULTS: There was moderately strong positive correlation (r=0.616, P=0.005) between GTVCT and MTV. HTV derived from F-MISO-PET/CT at 3-hours (HTV3hrs-F-MISO) showed strong positive correlation with GTVCT (r=0.753, P<0.0001) and MTV (r=0.796, P<0.0001) respectively. ADCmean showed strong positive correlations with SUVmean-5hrs-F-MISO (r=0.713, P=0.021) and SUVmin-5hrs-F-MISO (r=0.731, P=0.016) respectively. A moderate negative correlation (r=-0.500, P=0.049) was observed between ADCmean and MTV. At a median follow up of 44 months, the 5-year Kaplan-Meier estimates of loco-regional control, disease-free survival, and overall survival were 53%, 43%, and 40% respectively. Larger volume of primary tumor (GTVCT>22cc and MTV>7.9cc) and increasing hypoxia (HTV3hr-F-MSO>4.9cc) were associated with worse outcomes. CONCLUSIONS: Functional imaging represents an attractive and non-invasive modality to assess complex biological phenomena in solid tumors. Larger tumor volume and increasing hypoxia emerged as putative prognostic imaging biomarkers in HNSCC.


Asunto(s)
Neoplasias de Cabeza y Cuello , Tomografía Computarizada por Tomografía de Emisión de Positrones , Imagen de Difusión por Resonancia Magnética , Fluorodesoxiglucosa F18/metabolismo , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/terapia , Humanos , Hipoxia , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Tomografía de Emisión de Positrones , Radiofármacos , Carcinoma de Células Escamosas de Cabeza y Cuello/diagnóstico por imagen , Carcinoma de Células Escamosas de Cabeza y Cuello/terapia , Carga Tumoral
5.
Eur J Nucl Med Mol Imaging ; 47(3): 547-553, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31707429

RESUMEN

The 2015 American Thyroid Association (ATA) guideline have suggested modifications in the risk stratification (RS) for differentiated thyroid cancer (DTC) patients, introduced the concept of dynamic risk stratification (DRS) and redefined the role of radioactive iodine (RAI) in treatment algorithm. The aim of this retrospective audit was to assess the practical implications of these modifications in management of DTC. METHODS: A total of 138 DTC patients were stratified according to ATA 2009 and 2015 guidelines into low (LR), intermediate (IR) and high (HR) risk groups. Change in RS and in intention of RAI use was calculated. Deviation in administered RAI dosage from the guidelines was assessed. 1-year follow-up data was audited to assess how the DRS modified the initial risk estimate. RESULTS: A total of 11.6% of patients changed their RS categories in 2015 guidelines. A total of 10.1% got upstaged to HR, and 1.4% got downstaged to LR. In 2.17% of patients' intention of RAI use changed to remnant ablation from adjuvant therapy and 65% of the LR patients won't require any RAI therapy. A total of 26.7% of patients had received significantly more RAI dosage according to ATA 2015. At 1-year follow-up according to DRS 84% of LR, 75% of IR and 44% of HR patients showed excellent response (ER). CONCLUSION: More patients changed RS to HR than to LR. Intention of RAI use changed in only a small number of patients. Significantly higher dosage of RAI is being administered to patients in current practice. The effect of DRS in modifying the initial RS was most prominent in IR, with most showing ER to initial therapy.


Asunto(s)
Radioisótopos de Yodo , Neoplasias de la Tiroides , Humanos , Radioisótopos de Yodo/uso terapéutico , Estudios Retrospectivos , Neoplasias de la Tiroides/radioterapia , Neoplasias de la Tiroides/cirugía , Tiroidectomía , Estados Unidos
6.
Cancer ; 125(18): 3184-3197, 2019 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-31150120

RESUMEN

BACKGROUND: Because the addition of nimotuzumab to chemoradiation in patients with locally advanced head and neck cancer improved outcomes in a phase 2 study, the authors conducted a phase 3 study to confirm these findings. METHODS: This open-label, investigator-initiated, phase 3, randomized trial was conducted from 2012 to 2018. Adult patients with locally advanced head and neck cancer who were fit for radical chemoradiation were randomized 1:1 to receive either radical radiotherapy (66-70 grays) with concurrent weekly cisplatin (30 mg/m2 ) (CRT) or the same schedule of CRT with weekly nimotuzumab (200 mg) (NCRT).The primary endpoint was progression-free survival (PFS); key secondary endpoints were disease-free survival (DFS), duration of locoregional control (LRC), and overall survival (OS). An intent-to-treat analysis also was performed. RESULTS: In total, 536 patients were allocated equally to both treatment arms. The median follow-up was 39.13 months. The addition of nimotuzumab improved PFS (hazard ratio [HR], 0.69; 95% CI, 0.53-0.89; P = .004), LRC (HR, 0.67; 95% CI, 0.50-0.89; P = .006), and DFS (HR, 0.71; 95% CI, 0.55-0.92; P = .008) and had a trend toward improved OS (HR, 0.84; 95% CI, 0.65-1.08; P = .163). Grade 3 through 5 adverse events were similar between the 2 arms, except for a higher incidence of mucositis in the NCRT arm (66.7% vs 55.8%; P = .01). CONCLUSIONS: The addition of nimotuzumab to concurrent weekly CRT improves PFS, LRC, and DFS. This combination provides a novel alternative therapeutic option to a 3-weekly schedule of 100 mg/m2 cisplatin in patients with locally advanced head and neck cancer who are treated with radical-intent CRT.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Antineoplásicos Inmunológicos/uso terapéutico , Antineoplásicos/uso terapéutico , Quimioradioterapia/métodos , Cisplatino/uso terapéutico , Neoplasias de Cabeza y Cuello/terapia , Carcinoma de Células Escamosas de Cabeza y Cuello/terapia , Adulto , Anciano , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mucositis/etiología , Supervivencia sin Progresión , Modelos de Riesgos Proporcionales , Tasa de Supervivencia , Trombocitopenia/etiología , Adulto Joven
8.
Ann Surg Oncol ; 23(9): 3009-15, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27075323

RESUMEN

PURPOSE: Locally advanced (T3/T4) gallbladder cancers with large fixed portal nodes have a dismal prognosis. If undertaken, surgery entails extensive resections with high morbidity; therefore, in many centers, patients are offered palliative chemotherapy. In this prospective study, we used neoadjuvant concurrent chemoradiation with the intention of downstaging and facilitating R0 resection of these tumors. PATIENTS AND METHODS: Twenty-eight patients with locally advanced carcinoma gallbladder (stage III, having deep liver infiltrations and/or large portal nodes) underwent prior positron emission tomography/computed tomography to rule out metastatic disease. All were treated with concomitant chemoradiation using helical tomotherapy (dose of 57 Gy over 25 fractions to the gross tumor and 45 Gy over 25 fractions to the surrounding nodes) with injectable gemcitabine (300 mg/m(2)/week × 5 weeks). RESULTS: Of the 28 patients, 25 (89 %) successfully completed planned chemoradiation and 20 (71 %) achieved partial or complete radiologic response. Eighteen (64 %) patients were surgically explored, of whom 14 (56 %) achieved R0 resection. At the median follow-up of 37 months for the surviving patients, the median overall survival (OS) was 20 months for all patients. Only one patient recurred in the common bile duct postsurgery, whereas six patients had distant metastasis. The 5-year OS was 24 % for all patients and 47 % for patients with R0 resection. Biliary leak was seen in 6 (43 %) patients, of whom two required interventions. CONCLUSION: Locally advanced unresectable cancers may benefit from neoadjuvant chemoradiation to facilitate a curative resection with a good survival.


Asunto(s)
Adenocarcinoma/terapia , Quimioradioterapia , Neoplasias de la Vesícula Biliar/terapia , Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Femenino , Neoplasias de la Vesícula Biliar/diagnóstico por imagen , Neoplasias de la Vesícula Biliar/patología , Neoplasias de la Vesícula Biliar/cirugía , Humanos , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Invasividad Neoplásica , Estadificación de Neoplasias , Complicaciones Posoperatorias , Estudios Prospectivos , Tasa de Supervivencia , Resultado del Tratamiento
9.
J Surg Oncol ; 113(6): 652-8, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26847023

RESUMEN

INTRODUCTION: Incidental diagnosis of gall bladder cancer is increasing. The role of PET-CT in modifying the extent of surgery and adjuvant treatment is still unclear. We have evaluated the same in this study. METHODS: This is a prospective audit of gall bladder cancer from Tata Memorial Hospital, Mumbai, India. Patients found non-metastatic on initial imaging underwent laparotomy for revision surgery. RESULTS: One hundred and eight patients had a PET-CT scan done before revision surgery. Median duration of PET-CT from primary surgery was 42 days. PET scan of 64 (59.3%) patients had no uptake in body (N-PET). Rest had loco-regional uptake (L-PET). N-PET patients had lesser residual disease than L-PET patients (23% vs. 52%; P = 0.004). N-PET pT1b patients had no residual disease as compared to L-PET patients (0% vs. 33%, P = 0.028). pT1b patients did not have residual disease in liver wedge irrespective of PET status. Majority of the recurrences were distant and happened in pT2 patients. RFS was longer in N-PET than L-PET patients (P = 0.09) and in pT1b patients than pT2 and pT3 (P = 0.006). OS was longer in pT1b patients than pT2 patients (P = 0.038). CONCLUSIONS: PET-CT scan is useful to stratify patients with incidentally diagnosed gall bladder cancer for effective treatment. Liver wedge resection may be avoided in all pT1b patients. PET negative pT1b patients may be observed as chance of relapse is low. There may be a role for giving chemotherapy to all pT2 patients as they have high chance of recurrence and nodal metastases. J. Surg. Oncol. 2016;113:652-658. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Colecistectomía , Toma de Decisiones Clínicas/métodos , Neoplasias de la Vesícula Biliar/diagnóstico por imagen , Hallazgos Incidentales , Tomografía Computarizada por Tomografía de Emisión de Positrones , Auditoría Clínica , Estudios de Seguimiento , Neoplasias de la Vesícula Biliar/mortalidad , Neoplasias de la Vesícula Biliar/patología , Neoplasias de la Vesícula Biliar/cirugía , Hepatectomía , Humanos , Estadificación de Neoplasias , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento
12.
Endocr Pract ; 21(7): 719-24, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25716633

RESUMEN

OBJECTIVE: To describe the clinical presentation, biochemistry, imaging features, and treatment outcome of patients with primary adrenal lymphoma (PAL) presenting to a single tertiary care center. METHODS: We performed a retrospective analysis of case records of 7 patients diagnosed with PAL between January 2011 and May 2014 at our institution in Mumbai, India. RESULTS: Median age of presentation in our series was 48 years (range, 41 to 60 years), with a male to female ratio of 6:1. Bilateral adrenal involvement was seen in 4 of 7 patients (58%). Adrenal insufficiency (AI) was seen in 3 of the 4 patients with bilateral involvement (75%). Computed tomography showed slight to moderate contrast enhancement of adrenal masses in 4 of 5 patients (80%). Diffuse, large, B-cell lymphoma (DLBCL) was the most common immunophenotype (85%). One patient died due to rapid disease progression even before starting chemotherapy. Six patients were treated with chemotherapy and/or external beam radiotherapy. After 1 year, 2 more patients had died, whereas 4 patients were in remission. CONCLUSION: PAL should always be considered in differential diagnosis of bilateral adrenal mass with AI. DLBCL is the most common histologic subtype of PAL. Despite treatment, long-term prognosis of PAL remains poor.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/diagnóstico , Linfoma de Células B Grandes Difuso/diagnóstico , Adulto , Femenino , Humanos , India , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
13.
Clin Endocrinol (Oxf) ; 81(1): 31-7, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24528172

RESUMEN

CONTEXT: Localization of phosphatonin-producing mesenchymal tumours in patients with primary tumour-induced osteomalacia (pTIO) is challenging. Functional imaging plays an important role in the localization of these tumours. OBJECTIVE: We studied the relative performance of different functional imaging modalities ((18) F-FDG PET/CT, (99) Tc-HYNIC-TOC SPECT/CT and (68) Ga-DOTATATE PET/CT) in tumour localization in cases of pTIO. DESIGN AND METHODS: Retrospective chart evaluation of 16 patients with confirmed TIO treated from 2006 to 2013 was conducted in a tertiary care referral centre. RESULTS: Of 16, nine patients had pTIO. In these nine, the positivity rates of different functional imaging modalities were 50% for (18) F-FDG PET/CT (four of eight patients), 100% for (99) Tc-HYNIC-TOC SPECT/CT (six of six patients) and 100% for (68) Ga-DOTATATE PET/CT (seven of seven patients). Of nine patients, six were subjected to both the (99) Tc-HYNIC-TOC SPECT/CT and (68) Ga-DOTATATE PET/CT and all of them showed coregistration on the two scans. CONCLUSIONS: In patients with pTIO, the somatostatin receptor-based functional scans performed better than (18) F-FDG PET/CT in tumour localization. Amongst the somatostatin receptor-based scans, (99) Tc-HYNIC-TOC SPECT/CT and (68) Ga-DOTATATE PET/CT performed equally well for localization of tumours.


Asunto(s)
Fluorodesoxiglucosa F18 , Neoplasias de Tejido Conjuntivo/diagnóstico , Neoplasias de Tejido Conjuntivo/metabolismo , Tomografía de Emisión de Positrones/métodos , Receptores de Somatostatina/metabolismo , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de Tejido Conjuntivo/cirugía , Osteomalacia , Síndromes Paraneoplásicos , Estudios Retrospectivos , Adulto Joven
14.
Indian J Nucl Med ; 39(2): 129-134, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38989300

RESUMEN

Prostate-specific membrane antigen (PSMA) is a widely accepted and used tracer in staging and biochemical recurrences of prostate cancer. PSMA is extensively expressed in normal prostatic epithelial cells and prostate cancer cells, with some amount of expression also in nonprostatic cells. False-positive PSMA uptake in nonmalignant lesions creates ambiguity in disease detection. In such cases, histopathological correlation and radiological follow-up assist in clinical decision-making. In this case series, we illustrate a few cases where PSMA uptake was incidentally found in some of the commonly occurring benign conditions.

15.
BJR Open ; 6(1): tzad008, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38352184

RESUMEN

Objectives: Radiation therapy for lung cancer requires a gross tumour volume (GTV) to be carefully outlined by a skilled radiation oncologist (RO) to accurately pinpoint high radiation dose to a malignant mass while simultaneously minimizing radiation damage to adjacent normal tissues. This is manually intensive and tedious however, it is feasible to train a deep learning (DL) neural network that could assist ROs to delineate the GTV. However, DL trained on large openly accessible data sets might not perform well when applied to a superficially similar task but in a different clinical setting. In this work, we tested the performance of DL automatic lung GTV segmentation model trained on open-access Dutch data when used on Indian patients from a large public tertiary hospital, and hypothesized that generic DL performance could be improved for a specific local clinical context, by means of modest transfer-learning on a small representative local subset. Methods: X-ray computed tomography (CT) series in a public data set called "NSCLC-Radiomics" from The Cancer Imaging Archive was first used to train a DL-based lung GTV segmentation model (Model 1). Its performance was assessed using a different open access data set (Interobserver1) of Dutch subjects plus a private Indian data set from a local tertiary hospital (Test Set 2). Another Indian data set (Retrain Set 1) was used to fine-tune the former DL model using a transfer learning method. The Indian data sets were taken from CT of a hybrid scanner based in nuclear medicine, but the GTV was drawn by skilled Indian ROs. The final (after fine-tuning) model (Model 2) was then re-evaluated in "Interobserver1" and "Test Set 2." Dice similarity coefficient (DSC), precision, and recall were used as geometric segmentation performance metrics. Results: Model 1 trained exclusively on Dutch scans showed a significant fall in performance when tested on "Test Set 2." However, the DSC of Model 2 recovered by 14 percentage points when evaluated in the same test set. Precision and recall showed a similar rebound of performance after transfer learning, in spite of using a comparatively small sample size. The performance of both models, before and after the fine-tuning, did not significantly change the segmentation performance in "Interobserver1." Conclusions: A large public open-access data set was used to train a generic DL model for lung GTV segmentation, but this did not perform well initially in the Indian clinical context. Using transfer learning methods, it was feasible to efficiently and easily fine-tune the generic model using only a small number of local examples from the Indian hospital. This led to a recovery of some of the geometric segmentation performance, but the tuning did not appear to affect the performance of the model in another open-access data set. Advances in knowledge: Caution is needed when using models trained on large volumes of international data in a local clinical setting, even when that training data set is of good quality. Minor differences in scan acquisition and clinician delineation preferences may result in an apparent drop in performance. However, DL models have the advantage of being efficiently "adapted" from a generic to a locally specific context, with only a small amount of fine-tuning by means of transfer learning on a small local institutional data set.

16.
Cancer Biother Radiopharm ; 39(1): 82-91, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38265675

RESUMEN

Background: Selective internal radiation therapy (SIRT) using a suitable ß--emitting radionuclide is a promising treatment modality for unresectable liver carcinoma. Yttrium-90 (90Y) [T1/2 = 64.2 h, Eß(max) = 2.28 MeV, no detectable γ-photon] is the most preferred radioisotope for SIRT owing to its favorable decay characteristics. Objective: The present study describes indigenous development and evaluation of intrinsically radiolabeled [90Y]yttria alumino silicate ([90Y]YAS) glass microsphere, a formulation biosimilar to "TheraSphere" (commercially available, U.S. FDA-approved formulation), for SIRT of unresectable liver carcinoma in human patients. Methods: YAS glass microspheres of composition 40Y2O3-20Al2O3-40SiO2 (w/w) and diameter ranging between 20 and 36 µm were synthesized with almost 100% conversion efficiency and >99% sphericity. Intrinsically labeled [90Y]YAS glass microspheres were produced by thermal neutron irradiation of cold YAS glass microspheres in a research reactor. Subsequent to in vitro evaluations and in vivo studies in healthy Wistar rats, customized doses of [90Y]YAS glass microspheres were administered in human patients. Results: [90Y]YAS glass microspheres were produced with 137.7 ± 8.6 MBq/mg YAS glass (∼6800 Bq per microsphere) specific activity and 99.94% ± 0.02% radionuclidic purity at the end of irradiation. The formulation exhibited excellent in vitro stability in human serum and showed >97% retention in the liver up to 7 d post-administration when biodistribution studies were carried out in healthy Wistar rats. Yttrium-90 positron emission tomography scans recorded at different time points post-administration of customized dose of [90Y]YAS glass microspheres in human patients showed near-quantitative retention of the formulation in the injected lobe. Conclusions: The study confirmed the suitability of indigenously prepared [90Y]YAS glass microspheres for clinical use in the treatment of unresectable hepatocellular carcinoma.


Asunto(s)
Biosimilares Farmacéuticos , Carcinoma Hepatocelular , Embolización Terapéutica , Neoplasias Hepáticas , Itrio , Ratas , Animales , Humanos , Microesferas , Ratas Wistar , Distribución Tisular , Análisis Costo-Beneficio , Neoplasias Hepáticas/patología , Radioisótopos de Itrio/uso terapéutico , Carcinoma Hepatocelular/radioterapia , Carcinoma Hepatocelular/tratamiento farmacológico , Radiofármacos/uso terapéutico
17.
Int J Radiat Oncol Biol Phys ; 118(5): 1541-1551, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37660737

RESUMEN

PURPOSE: The objective of this study was to compare clinical outcomes of intensity-modulated radiation therapy (IMRT) alone versus IMRT + brachytherapy (BT) in patients with T1-T2N0M0 oropharyngeal squamous cell cancers (OPSCC). METHODS AND MATERIALS: This open-label randomized controlled trial was conducted at Tata Memorial Hospital, Mumbai, India. Patients with stage I and II OPSCC were considered for IMRT to a dose of 50 Gy/25 fractions/5 weeks in phase I followed by randomization (1:1) to further treatment with IMRT (20 Gy/10 fractions/2 weeks) or BT (192Ir high dose rate, 21 Gy/7 fractions/2 fractions per day). The primary endpoint of the trial was the reduction in xerostomia at 6 months evaluated using 99mTc salivary scintigraphy. Severe salivary toxicity (xerostomia) was defined as posttreatment salivary excretion fraction ratio <45%. Secondary endpoints were local control, disease-free survival, and overall survival. RESULTS: Between November 2010 and February 2020, 90 patients were randomized to IMRT (n = 46) alone or IMRT + BT (n = 44). Eleven patients (8 residual/recurrent disease, 2 lost to follow-up, 1 second primary) in the IMRT arm and 9 patients (8 residual/recurrence, 1 lost to follow-up) in the BT arm were not evaluable at 6 months for the primary endpoint. At 6 months, xerostomia rates using salivary scintigraphy were 14% (5/35: 95% CI, 5%-30%) in the BT arm while it was seen in 44% (14/32: 95% CI, 26%-62%) in the IMRT arm (P = .008). Physician-rated Radiation Therapy Oncology Group grade ≥2 xerostomia at any time point was observed in 30% of patients (9/30) in the IMRT arm and 6.7% (2/30) in the BT arm (P = .02). At a median follow-up of 42.5 months, the 3-year local control in the IMRT arm was 56.4% (95% CI, 43%-73%) while it was 66.2% (95% CI, 53%-82%) in the BT arm (P = .24). CONCLUSIONS: The addition of BT to IMRT for T1-T2N0M0 OPSCC results in a significant reduction in xerostomia. This strongly supports the addition of BT to IMRT in suitable cases.


Asunto(s)
Braquiterapia , Neoplasias de Cabeza y Cuello , Neoplasias Orofaríngeas , Radioterapia de Intensidad Modulada , Xerostomía , Humanos , Radioterapia de Intensidad Modulada/efectos adversos , Radioterapia de Intensidad Modulada/métodos , Braquiterapia/efectos adversos , Braquiterapia/métodos , Carcinoma de Células Escamosas de Cabeza y Cuello , Xerostomía/etiología , Xerostomía/prevención & control , Neoplasias Orofaríngeas/radioterapia
18.
Indian J Nucl Med ; 39(2): 71-76, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38989301

RESUMEN

Purpose: We proposed to administer Lu-177-DOTATATE in intra-arterial (IA) mode for higher first-pass localization to somatostatin receptors, higher residence time in liver metastases, and more radiation to tumor. This study aimed at assessing early hematological, renal and hepatotoxicity; and objective response to IA peptide receptor radionuclide therapy (PRRT). Materials and Methods: Fourteen patients (4 females and 10 males) were prospectively assessed. 5/14 patients underwent 2 cycles, whereas 3/14 underwent 3 cycles, and 6/14 received 1 cycle of IA PRRT. 200 mCi of Lu-177-DOTATATE was administered in 15-20 min by IA route under angiographic guidance. Patients were asked to follow-up at 4 and 8 weeks with hematological, liver, and renal functional parameters, and Ga-68 DOTATATE positron emission tomography/computed tomography (PET/CT) after 8 weeks. Response was assessed using RECIST 1.1 and EORTC PET criteria. Results: Safety: 2/14 patients had high total and direct bilirubin, which reverted to normal after IA PRRT. Three patients had low albumin, which improved after 1 cycle. Nine patients showed no worsening of liver function. Two patients showed Grade 1 hematotoxicity which reverted to normal. Five patients showed high creatinine, but preserved glomerular filtration rate and EC clearance. On follow-up at 8 weeks, serum creatinine reverted to normal. Efficacy: In five patients who underwent 2 cycles of IA PRRT, 3 showed partial response (PR) on RECIST 1.1 and partial metabolic response (PMR) on EORTC criteria, whereas 2 showed stable disease (SD). In patients who underwent 3 cycles, 1 showed SD, whereas other patient showed PMR on DOTANOC PET/CT, with PR in size. Among the remaining seven patients, 5 showed PMR, whereas the other 2 showed SD. Thus 9/14 patients showed PR, whereas 5 showed SD on metabolic and size criteria. Conclusions: IA PRRT is a safe and efficacious approach for the treatment of liver dominant metastatic neuroendocrine tumors.

19.
Nucl Med Commun ; 45(7): 601-611, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38686492

RESUMEN

AIM: To evaluate relationship between metabolic PET metabolic parameters and size of the primary tumor, various histopathological subtypes of renal cell carcinoma (RCC) and Fuhrman grade of the tumors. MATERIAL AND METHODS: Retrospective analysis of 93 biopsy-proven RCC patients who underwent pretreatment flourine 18 flourodeoxyglucose PET/computed tomography ( 18 F FDG PET/CT) was performed. Quantitative PET parameters, size of the primary tumor, histopathological subtypes and Fuhrman grades of the tumor were extracted. We tried to assess if there was any significant difference in the metabolic patterns of various histopathological subtypes of RCCs, Fuhrman grade of the tumors and size of the primary tumor. RESULTS: A significant correlation was noted between the size of primary tumor and maximum standardized uptake value (SUV max ), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) ( P  < 0.01, P  < 0.001 and P  < 0.001, respectively). SUV max values correlated significantly with the histopathological subtype ( P  < 0.001). Further sub-analyses was also done by segregating the patients into Low grade (Fuhrman grade 1 and 2) vs. High grade (Fuhrman grade 3 and 4). SUV max , MTV and TLG were significantly different between high grade vs. low grade tumors. ROC analysis yielded cut off values for SUV max , MTV and TLG to differentiate between high grade from low grade tumors. CONCLUSION: FDG PET/CT with the use of metabolic PET parameters can differentiate between different histopathological subtypes of RCC. Incorporation of metabolic parameters into clinical practice can potentially noninvasively identify patients with low-grade vs. high-grade RCC.


Asunto(s)
Carcinoma de Células Renales , Fluorodesoxiglucosa F18 , Neoplasias Renales , Clasificación del Tumor , Tomografía Computarizada por Tomografía de Emisión de Positrones , Humanos , Carcinoma de Células Renales/diagnóstico por imagen , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/patología , Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/metabolismo , Neoplasias Renales/patología , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Anciano , Adulto , Anciano de 80 o más Años , Diagnóstico Diferencial , Carga Tumoral
20.
Indian J Cancer ; 61(Suppl 1): S1-S28, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38424680

RESUMEN

ABSTRACT: PET/CT and radioisotope therapy are diagnostic and therapeutic arms of Nuclear Medicine, respectively. With the emergence of better technology, PET/CT has become an accessible modality. Diagnostic tracers exploring disease-specific targets has led the clinicians to look beyond FDG PET. Moreover, with the emergence of theranostic pairs of radiopharmaceuticals, radioisotope therapy is gradually making it's way into treatment algorithm of common cancers in India. We therefore would like to discuss in detail the updates in PET/CT imaging and radionuclide therapy and generate a consensus-driven evidence based document which would guide the practitioners of Oncology.


Asunto(s)
Neoplasias , Medicina Nuclear , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Neoplasias/diagnóstico por imagen , Neoplasias/radioterapia , Tomografía de Emisión de Positrones/métodos , Radiofármacos/uso terapéutico , Radioisótopos , Fluorodesoxiglucosa F18
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA