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Dive into the research topics where Govindarajan Narayanan is active.

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Featured researches published by Govindarajan Narayanan.


Journal of Surgical Oncology | 2013

Safety and early efficacy of irreversible electroporation for hepatic tumors in proximity to vital structures

Robert M. Cannon; Susan Ellis; David Hayes; Govindarajan Narayanan; Robert C.G. Martin

Irreversible electroporation (IRE) has shown promise for ablation of lesions in proximity to vital structures in the preclinical setting. This study aims to evaluate the safety and efficacy of IRE for hepatic tumors in the clinical setting.


BMC Cancer | 2012

A retrospective study of neoadjuvant FOLFIRINOX in unresectable or borderline-resectable locally advanced pancreatic adenocarcinoma

Peter J. Hosein; J. Macintyre; Carolina Kawamura; Jennifer Cudris Maldonado; Vinicius Ernani; Arturo Loaiza-Bonilla; Govindarajan Narayanan; Afonso Ribeiro; L. Portelance; Jaime R. Merchan; Joe U. Levi; Caio Rocha-Lima

Background5-fluorouracil, leucovorin, irinotecan and oxaliplatin (FOLFIRINOX) is superior to gemcitabine in patients with metastatic pancreatic cancer who have a good performance status. We investigated this combination as neoadjuvant therapy for locally advanced pancreatic cancer (LAPC).MethodsIn this retrospective series, we included patients with unresectable LAPC who received neoadjuvant FOLFIRINOX with growth factor support. The primary analysis endpoint was R0 resection rate.ResultsEighteen treatment-naïve patients with unresectable or borderline resectable LAPC were treated with neoadjuvant FOLFIRINOX. The median age was 57.5 years and all had ECOG PS of 0 or 1. Eleven (61 %) had tumors in the head of the pancreas and 9 (50 %) had biliary stents placed prior to chemotherapy. A total of 146 cycles were administered with a median of 8 cycles (range 3-17) per patient. At maximum response or tolerability, 7 (39 %) were converted to resectability by radiological criteria; 5 had R0 resections, 1 had an R1 resection, and 1 had unresectable disease. Among the 11 patients who remained unresectable after FOLFIRINOX, 3 went on to have R0 resections after combined chemoradiotherapy, giving an overall R0 resection rate of 44 % (95 % CI 22–69 %). After a median follow-up of 13.4 months, the 1-year progression-free survival was 83 % (95 % CI 59-96 %) and the 1-year overall survival was 100 % (95 % CI 85-100 %). Grade 3/4 chemotherapy-related toxicities were neutropenia (22 %), neutropenic fever (17 %), thrombocytopenia (11 %), fatigue (11 %), and diarrhea (11 %). Common grade 1/2 toxicities were neutropenia (33 %), anemia (72 %), thrombocytopenia (44 %), fatigue (78 %), nausea (50 %), diarrhea (33 %) and neuropathy (33 %).ConclusionsFOLFIRINOX followed by chemoradiotherapy is feasible as neoadjuvant therapy in patients with unresectable LAPC. The R0 resection rate of 44 % in this population is promising. Further studies are warranted.


Journal of Vascular and Interventional Radiology | 2012

Percutaneous irreversible electroporation for downstaging and control of unresectable pancreatic adenocarcinoma.

Govindarajan Narayanan; Peter J. Hosein; G. Arora; K.J. Barbery; Tatiana Froud; Alan S. Livingstone; Dido Franceschi; Caio Max S. Rocha Lima; Jose M. Yrizarry

PURPOSE Treatment of unresectable locally advanced pancreatic cancer (LAPC) usually includes chemotherapy and/or radiation therapy in an attempt to downstage these tumors to the extent of resectability, but outcomes remain poor. Irreversible electroporation (IRE) is an ablative modality that may be useful in this population. The aim of this study was to evaluate the safety of percutaneous IRE in patients with pancreatic adenocarcinoma. MATERIALS AND METHODS IRE was performed in patients with pancreatic cancer whose tumors remained unresectable after, or who were intolerant of, standard therapy. The procedures were all done percutaneously under general anesthesia. Patients were then followed for adverse events, tumor response, and survival. RESULTS Fifteen IRE procedures were performed in 14 patients (one was treated twice). Three patients had metastatic disease and 11 had LAPC. All patients had received chemotherapy previously, and 11 had received radiation. The median tumor size was 3.3 cm (range, 2.5-7 cm). Immediate and 24-hour postprocedural scans demonstrated patent vasculature in the treatment zone in all patients. Two patients underwent surgery 4 and 5 months after IRE, respectively. Both had margin-negative resections, and one had a pathologic complete response; both remain disease-free after 11 and 14 months, respectively. Complications included spontaneous pneumothorax during anesthesia (n = 1) and pancreatitis (n = 1), and both patients recovered completely. There were no deaths directly related to the procedure. All three patients with metastatic disease at IRE died from progression of their disease. CONCLUSIONS Percutaneous IRE for pancreatic adenocarcinoma is feasible and safe. A prospective trial is being planned.


Liver cancer | 2015

Image-Guided Ablation of Malignant Liver Tumors: Recommendations for Clinical Validation of Novel Thermal and Non-Thermal Technologies - A Western Perspective.

Riccardo Lencioni; Thierry de Baere; Robert C.G. Martin; Charles W Nutting; Govindarajan Narayanan

Background: Image-guided ablation is used to treat patients with unresectable malignant hepatic tumors that are limited in number and size, especially hepatocellular carcinoma (HCC) and colorectal hepatic metastases. While radiofrequency ablation (RFA) has been the most popular technique, several alternate options for focal tissue destruction have recently attracted attention. These technologies appear to be able to overcome some specific limitations of RFA. Currently, there is no accepted algorithm for the use of the different techniques for image-guided ablation. Summary: A panel of physicians practicing in North America or Europe met to develop a set of recommendations aimed at providing directions for clinical validation of energy-based, thermal and non-thermal image-guided ablation technologies in the treatment of malignant liver tumors. The recommendations were developed through a critical appraisal of potential advantages and disadvantages of each ablation technology, based on experimental findings and available data, as well as on critical considerations for their clinical validation in hepatic tumor treatment from a Western perspective. Key Messages: Significant variability appears to exist among the different equipment and devices within each type of technology. A comprehensive understanding of the data and a critical appraisal of the efficacy and safety profile of each ablation system is required. Clinical practice guidelines should include specific information of the recommended techniques and protocols instead of a generic indication of the technology.


Oncologist | 2011

Transarterial Chemoembolization and Selective Internal Radiation for the Treatment of Patients with Metastatic Neuroendocrine Tumors: A Comparison of Efficacy and Cost

Ryan Whitney; V. Válek; Joan Falcó Fagés; Agustin A. Garcia; Govindarajan Narayanan; Cliff Tatum; Mike Hahl; Robert C.G. Martin

BACKGROUND Hepatic arterial therapy (HAT) has been proven to be effective at palliation of hormonal symptoms of metastatic neuroendocrine tumors (NETs), as well as a means of cytoreduction. Recently, the newer modalities of yttrium-90 and drug-eluting beads with doxorubicin (DEBDOX) have been reported to be effective in the treatment of metastatic NETs. The aim of this study was to compare the safety, efficacy, and cost of selective internal radiation with DEB therapy. METHODS An institutional review board-approved, multicenter, multinational prospective treatment registry to investigate the safety and efficacy of yttrium-90 and doxorubicin microspheres was reviewed. RESULTS In all, 43 patients underwent a combined 69 HAT treatments, with 15 patients receiving 23 yttrium-90 treatments and 28 patients receiving 46 DEBDOX treatments. The extent of disease-based on the number of lesions, bilobar distribution, patient performance status, and size of largest lesion-was similar in both the yttrium-90 and DEBDOX groups. After a median follow-up of 12 months, response rates were similar with the two treatments, but then there was a significantly lower response rate in the yttrium-90 group at 12 months than in the DEBDOX group. In an evaluation of cost for the two treatments, the median cost for yttrium-90 was


Pancreatology | 2015

Full dose neoadjuvant FOLFIRINOX is associated with prolonged survival in patients with locally advanced pancreatic adenocarcinoma

Moh'd M. Khushman; Naomi Dempsey; Jennifer Cudris Maldonado; Arturo Loaiza-Bonilla; Michel Velez; Lauren Carcas; Daniel Dammrich; Jorge Hurtado-Cordovi; Ritesh Parajuli; Terri Pollack; Ana Paula P. Harwood; J. Macintyre; Ching Wei D. Tzeng; Jaime R. Merchan; Maria H. Restrepo; Ikechukwu Immanuel Akunyili; Afonso Ribeiro; Govindarajan Narayanan; L. Portelance; Danny Sleeman; Joe U. Levi; Caio Max S. Rocha Lima; Peter J. Hosein

25,243 and the median cost for DEBDOX was


Journal of The American College of Surgeons | 2010

Liver transplantation for hepatocellular carcinoma in the model for end-stage liver disease era.

David Levi; Andreas G. Tzakis; Paul Martin; Seigo Nishida; E. Island; Jang Moon; Gennaro Selvaggi; Akin Tekin; Beatrice L. Madrazo; Govindarajan Narayanan; Lynn G. Feun; Panagiotis Tryphonopoulos; Nikolaos Skartsis; Alan S. Livingstone

13,400. CONCLUSION HAT is a safe and effective therapy in patients with unresectable NETs to the liver. The size of the lesions, total lesion volume, and expense of therapy need to be considered when choosing which HAT method is optimal.


Seminars in Interventional Radiology | 2013

Irreversible Electroporation of Hepatic Malignancy

Govindarajan Narayanan; Tatiana Froud; Rekhaben Suthar; Katuska Barbery

BACKGROUND The efficacy of FOLFIRINOX for metastatic pancreatic cancer has led to its use in patients with earlier stages of disease. This study retrospectively analyzed a cohort of patients with locally-advanced pancreatic cancer (LAPC) treated with FOLFIRINOX. METHODS Between 2008 and 2013, 51 treatment-naïve patients with LAPC at a single institution received first-line FOLFIRINOX with neoadjuvant intent, at the full dose as described in the PRODIGE 4/ACCORD 11 study. Combined chemoradiation was administered for those who remained unresectable after maximum response to chemotherapy. The primary outcome measure was overall survival (OS), and secondary outcomes were progression-free survival (PFS) and margin-negative (R0) resection rate, and toxicity profile. RESULTS A total of 429 cycles of FOLFIRINOX were given with a median of 8 cycles (range 2-29) per patient; 66% of cycles were full dose. After chemotherapy, 27 (53%) received chemoradiation. The median OS was 35.4 months (95% CI 25.8-45). Ten (4 borderline resectable and 6 unresectable) patients had successful R0 resections; those who had R0 resections had a significantly longer survival than those who did not (3-year OS rate 67% versus 21%, log rank p = 0.042). Increasing number of full-dose cycles was significantly associated with increased survival. The toxicity profile was similar to previous reports of this regimen. CONCLUSIONS FOLFIRINOX is feasible as neoadjuvant therapy for LAPC. Although the R0 resection rate was only 20%, the median OS of almost 3 years appears promising. Dose intensity and duration were associated with increased survival in this study, arguing against dose attenuated versions of this regimen.


Journal of Vascular and Interventional Radiology | 2014

Transarterial Treatment of Colorectal Cancer Liver Metastases with Irinotecan-Loaded Drug-Eluting Beads: Technical Recommendations

Riccardo Lencioni; Camillo Aliberti; Thierry de Baere; Ricardo García-Mónaco; Govindarajan Narayanan; Elizabeth O’Grady; William S. Rilling; D. Walker; Robert C.G. Martin

BACKGROUND Since March 2002, the United Network for Organ Sharing liver allocation policy has given extra priority to patients with hepatocellular carcinoma (HCC) who meet specific medical criteria. This study reviews our experience with liver transplantation for HCC under this system. STUDY DESIGN Between March 2002 and April 2009, 244 patients with HCC underwent primary liver or liver-kidney transplantation under the current allocation system at the University of Miami. Outcomes including HCC recurrence-free survival (RFS) and patient survival (PS) were assessed retrospectively. Clinical variables that predicted outcomes were analyzed. RESULTS The median time from listing to transplantation was 48 days. The median follow-up was 27.4 months, with an observed recurrence rate of 10.7%. The RFS rates at 1, 3, and 5 years after transplantation were 96.0%, 89.0%, and 83.6%, respectively. The PS rates at 1, 3, and 5 years after transplantation were 86.3%, 71.5%, and 61.7%, respectively. Among patients diagnosed with T2 HCC, a trend toward improved RFS was observed for those who received preoperative ablative therapy; PS was similar (p > 0.05). Outcomes (RFS and PS) for patients with T3 HCC were similar to those in patients with T2 HCC (p > 0.05). Patients with an alpha-fetoprotein >100 ng/mL had an RFS that was inferior to that in patients with an alpha-fetoprotein < or =100 ng/mL (p < 0.0001). CONCLUSIONS Under the current allocation system, transplantation for HCC results in excellent RFS; PS depends on factors other than HCC; the value of preoperative ablative therapy for patients with T2 HCC is uncertain; the current criteria could be expanded to include selected patients with T3 HCC; and an elevated AFP level is associated with an increased risk of HCC recurrence after transplantation.


Journal of Vascular and Interventional Radiology | 2014

Percutaneous Irreversible Electroporation for the Treatment of Colorectal Cancer Liver Metastases with a Proposal for a New Response Evaluation System

Peter J. Hosein; Ana Echenique; Arturo Loaiza-Bonilla; Tatiana Froud; K.J. Barbery; Caio Max S. Rocha Lima; Jose M. Yrizarry; Govindarajan Narayanan

Hepatocellular carcinoma (HCC) is a worldwide problem of epidemic proportions, best treated in a multidisciplinary setting. Major advances have been made in all specialties that manage patients with HCC, with surgical options at one end of the spectrum and palliative chemotherapy on the other, and the vast majority of patients require the involvement and expertise of interventional oncology. Several ablative and transarterial technologies are currently available. Irreversible electroporation (IRE) is a new ablative technology that uses high-voltage, low-energy DC current to create nanopores in the cell membrane, disrupting the homeostasis mechanism and inducing cell death by initiating apoptosis. This article discusses the evolution of IRE as well as its safety and efficacy in the context of other ablative therapies in the treatment of hepatic malignancies.

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