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Gastroenterology | 2010

Radioembolization for Hepatocellular Carcinoma Using Yttrium-90 Microspheres: A Comprehensive Report of Long-term Outcomes

Riad Salem; Robert J. Lewandowski; Mary F. Mulcahy; Ahsun Riaz; Robert K. Ryu; S.M. Ibrahim; Bassel Atassi; Talia Baker; Vanessa L. Gates; Frank H. Miller; Kent T. Sato; E. D. Wang; Ramona Gupta; Al B. Benson; Steven Newman; Reed A. Omary; Michael Abecassis; Laura Kulik

BACKGROUND & AIMS Hepatocellular carcinoma (HCC) has limited treatment options; long-term outcomes following intra-arterial radiation are unknown. We assessed clinical outcomes of patients treated with intra-arterial yttrium-90 microspheres (Y90). METHODS Patients with HCC (n = 291) were treated with Y90 as part of a single-center, prospective, longitudinal cohort study. Toxicities were recorded using the Common Terminology Criteria version 3.0. Response rate and time to progression (TTP) were determined using World Health Organization (WHO) and European Association for the Study of the Liver (EASL) guidelines. Survival by stage was assessed. Univariate/multivariate analyses were performed. RESULTS A total of 526 treatments were administered (mean, 1.8; range, 1-5). Toxicities included fatigue (57%), pain (23%), and nausea/vomiting (20%); 19% exhibited grade 3/4 bilirubin toxicity. The 30-day mortality rate was 3%. Response rates were 42% and 57% based on WHO and EASL criteria, respectively. The overall TTP was 7.9 months (95% confidence interval, 6-10.3). Survival times differed between patients with Child-Pugh A and B disease (A, 17.2 months; B, 7.7 months; P = .002). Patients with Child-Pugh B disease who had portal vein thrombosis (PVT) survived 5.6 months (95% confidence interval, 4.5-6.7). Baseline age; sex; performance status; presence of portal hypertension; tumor distribution; levels of bilirubin, albumin, and alpha-fetoprotein; and WHO/EASL response rate predicted survival. CONCLUSIONS Patients with Child-Pugh A disease, with or without PVT, benefited most from treatment. Patients with Child-Pugh B disease who had PVT had poor outcomes. TTP and overall survival varied by patient stage at baseline. These data can be used to design future Y90 trials and to describe Y90 as a potential treatment option for patients with HCC.


Gastroenterology | 2011

Radioembolization results in longer time-to-progression and reduced toxicity compared with chemoembolization in patients with hepatocellular carcinoma

Riad Salem; Robert J. Lewandowski; Laura Kulik; Ahsun Riaz; Robert K. Ryu; Kent T. Sato; Ramona Gupta; Paul Nikolaidis; Frank H. Miller; Vahid Yaghmai; S.M. Ibrahim; Seanthan Senthilnathan; Talia Baker; Vanessa L. Gates; Bassel Atassi; Steven Newman; Khairuddin Memon; Richard Chen; Robert L. Vogelzang; Albert A. Nemcek; Scott A. Resnick; Howard B. Chrisman; James Carr; Reed A. Omary; Michael Abecassis; Al B. Benson; Mary F. Mulcahy

BACKGROUND & AIMS Chemoembolization is one of several standards of care treatment for hepatocellular carcinoma (HCC). Radioembolization with Yttrium-90 microspheres is a novel, transarterial approach to radiation therapy. We performed a comparative effectiveness analysis of these therapies in patients with HCC. METHODS We collected data from 463 patients who were treated with transarterial locoregional therapies (chemoembolization or radioembolization) over a 9-year period. We excluded patients who were not appropriate for comparison and analyzed data from 245 (122 who received chemoembolization and 123 who received radioembolization). Patients were followed for signs of toxicity; all underwent imaging analysis at baseline and follow-up time points. Overall survival was the primary outcome measure. Secondary outcomes included safety, response rate, and time-to-progression. Uni- and multivariate analyses were performed. RESULTS Abdominal pain and increased transaminase activity were more frequent following chemoembolization (P < .05). There was a trend that patients treated with radioembolization had a higher response rate than with chemoembolization (49% vs 36%, respectively, P = .104). Although time-to-progression was longer following radioembolization than chemoembolization (13.3 months vs 8.4 months, respectively, P = .046), median survival times were not statistically different (20.5 months vs 17.4 months, respectively, P = .232). Among patients with intermediate-stage disease, survival was similar between groups that received chemoembolization (17.5 months) and radioembolization (17.2 months, P = .42). CONCLUSIONS Patients with HCC treated by chemoembolization or radioembolization with Yttrium-90 microspheres had similar survival times. Radioembolization resulted in longer time-to-progression and less toxicity than chemoembolization. Post hoc analyses of sample size indicated that a randomized study with > 1000 patients would be required to establish equivalence of survival times between patients treated with these two therapies.


American Journal of Transplantation | 2009

A Comparative Analysis of Transarterial Downstaging for Hepatocellular Carcinoma: Chemoembolization Versus Radioembolization

Robert J. Lewandowski; Laura Kulik; Ahsun Riaz; Seanthan Senthilnathan; Mary F. Mulcahy; Robert K. Ryu; S.M. Ibrahim; Kent T. Sato; Talia Baker; Frank H. Miller; Reed A. Omary; Michael Abecassis; Riad Salem

Chemoembolization and other ablative therapies are routinely utilized in downstaging from United Network for Organ Sharing (UNOS) T3 to T2, thus potentially making patients transplant candidates under the UNOS model for end‐stage liver disease (MELD) upgrade for hepatocellular carcinoma (HCC). This study was undertaken to compare the downstaging efficacy of transarterial chemoembolization (TACE) versus transarterial radioembolization. Eighty‐six patients were treated with either TACE (n = 43) or transarterial radioembolization with Yttrium‐90 microspheres (TARE‐Y90; n = 43). Median tumor size was similar (TACE: 5.7 cm, TARE‐Y90: 5.6 cm). Partial response rates favored TARE‐Y90 versus TACE (61% vs. 37%). Downstaging to UNOS T2 was achieved in 31% of TACE and 58% of TARE‐Y90 patients. Time to progression according to UNOS criteria was similar for both groups (18.2 months for TACE vs. 33.3 months for TARE‐Y90, p = 0.098). Event‐free survival was significantly greater for TARE‐Y90 than TACE (17.7 vs. 7.1 months, p = 0.0017). Overall survival favored TARE‐Y90 compared to TACE (censored 35.7/18.7 months; p = 0.18; uncensored 41.6/19.2 months; p = 0.008). In conclusion, TARE‐Y90 appears to outperform TACE for downstaging HCC from UNOS T3 to T2.


Journal of Vascular and Interventional Radiology | 2009

Complications Following Radioembolization with Yttrium-90 Microspheres: A Comprehensive Literature Review

Ahsun Riaz; Robert J. Lewandowski; Laura Kulik; Mary F. Mulcahy; Kent T. Sato; Robert K. Ryu; Reed A. Omary; Riad Salem

The past decade has seen significant advancement in the locoregional management of liver tumors; novel and promising therapies such as transarterial chemoembolization, radioembolization, and radiofrequency ablation are now available. The development of new techniques and devices has led to the improved safety and efficacy profiles of external-beam radiation. Radioembolization with yttrium-90 ((90)Y) microspheres has emerged as a safe and efficacious treatment modality for liver malignancies. The purpose of this article is to present a comprehensive evidence-based review of the complications and adverse events that may be associated with radioembolization with (90)Y microspheres. Strategies to mitigate these adverse events are also discussed.


Hepatology | 2009

Radiologic–pathologic correlation of hepatocellular carcinoma treated with internal radiation using yttrium‐90 microspheres

Ahsun Riaz; Laura Kulik; Robert J. Lewandowski; Robert K. Ryu; Georgia Giakoumis Spear; Mary F. Mulcahy; Michael Abecassis; Talia Baker; Vanessa L. Gates; Ritu Nayar; Frank H. Miller; Kent T. Sato; Reed A. Omary; Riad Salem

We present the correlation between radiologic and pathologic findings in HCC patients who underwent radioembolization with yttrium‐90 (90Y) microspheres prior to resection or transplantation. Thirty‐five patients with a total of 38 lesions who underwent liver explantation after 90Y radioembolization were studied. Imaging surrogates following treatment were evaluated; the explants were examined for assessment of necrosis by pathology. The correlation betwen radiologic and histologic findings of the treated lesions was analyzed. Twenty‐three of 38 (61%) target lesions showed complete pathologic necrosis. All target lesions demonstrated some degree of histologic necrosis at explant. Complete histologic necrosis was seen in 89% of lesions with pretreatment size <3 cm. Complete pathologic necrosis was seen in 100%, 78%, and 93% of the lesions that were shown to have complete response by European Association for the Study of the Liver (EASL) necrosis criteria, partial response by World Health Organizaton (WHO) criteria, or thin rim enhancement on posttreatment imaging, respectively. In contrast, complete pathologic necrosis was seen in only 52% and 38% of the lesions that showed partial response by EASL criteria and peripheral nodular enhancement, respectively. Conclusion: Post‐radioembolization imaging findings of response by EASL and WHO criteria are predictive of the degree of pathologic necrosis. Rim enhancement was an imaging characteristic that correlated well with histologic necrosis. (HEPATOLOGY 2009.)


Journal of Clinical Oncology | 2009

Alpha-Fetoprotein Response After Locoregional Therapy for Hepatocellular Carcinoma: Oncologic Marker of Radiologic Response, Progression, and Survival

Ahsun Riaz; Robert K. Ryu; Laura Kulik; Mary F. Mulcahy; Robert J. Lewandowski; Jeet Minocha; S.M. Ibrahim; Kent T. Sato; Talia Baker; Frank H. Miller; Steven Newman; Reed A. Omary; Michael Abecassis; Al B. Benson; Riad Salem

PURPOSE Alpha-fetoprotein (AFP) is considered to be an indicator of tumor activity in hepatocellular carcinoma (HCC). We present a novel correlation of AFP response to radiologic response, time-to-progression (TTP), progression-free survival (PFS), and overall survival (OS) in patients treated with locoregional therapies. PATIENTS AND METHODS Four hundred sixty-three patients with HCC were treated with chemoembolization or radioembolization at our institution. One hundred twenty-five patients with baseline AFP higher than 200 ng/mL were studied for this analysis. AFP response was defined as more than 50% decrease from baseline. One hundred nineteen patients with follow-up imaging were studied for the AFP imaging correlation analysis. AFP response was correlated to radiologic response, TTP, PFS, and OS. Multivariate analyses were performed. RESULTS Eighty-one patients (65%) showed AFP response. AFP response was seen in 26 (55%) of 47 and 55 (70%) of 78 of patients treated with chemoembolization and radioembolization, respectively (P = .12). WHO response was seen in 41 (53%) of 77 and 10 (24%) of 42 of AFP responders and nonresponders, respectively (P = .002). The hazard ratio (HR) for TTP in AFP nonresponders compared with responders was 2.8 (95% CI, 1.5 to 5.1). The HR for PFS was 4.2 (95% CI, 2.4 to 7.2) in AFP nonresponders compared with responders. The HR for OS in AFP nonresponders compared with responders was 5.5 (95% CI, 3.1 to 9.9) and 2.7 (95% CI, 1.6 to 4.6) on univariate and multivariate analyses, respectively. CONCLUSION The data presented support the use of AFP response seen after locoregional therapy as an ancillary method of assessing tumor response and survival, as well as an early objective screening tool for progression by imaging.


Radiology | 2010

Chemoembolization for Hepatocellular Carcinoma: Comprehensive Imaging and Survival Analysis in a 172-Patient Cohort

Robert J. Lewandowski; Mary F. Mulcahy; Laura Kulik; Ahsun Riaz; Robert K. Ryu; Talia Baker; S.M. Ibrahim; Michael I. Abecassis; Frank H. Miller; Kent T. Sato; Seanthan Senthilnathan; Scott A. Resnick; Ramona Gupta; Richard Chen; Steven Newman; Howard B. Chrisman; Albert A. Nemcek; Robert L. Vogelzang; Reed A. Omary; Al B. Benson; Riad Salem

PURPOSE To determine comprehensive imaging and long-term survival outcome following chemoembolization for hepatocellular carcinoma (HCC). MATERIALS AND METHODS One hundred seventy-two patients with HCC treated with chemoembolization were studied retrospectively in an institutional review board approved protocol; this study was HIPAA compliant. Baseline laboratory and imaging characteristics were obtained. Clinical and laboratory toxicities following treatment were assessed. Imaging characteristics following chemoembolization were evaluated to determine response rates (size and necrosis) and time to progression (TTP). Survival from the time of first chemoembolization treatment was calculated. Subanalyses were performed by stratifying the population according to Child-Pugh, United Network for Organ Sharing, and Barcelona Clinic for Liver Cancer (BCLC) staging systems. RESULTS Cirrhosis was present in 157 patients (91%); portal hypertension was present in 139 patients (81%). Eleven patients (6%) had metastases at baseline. Portal vein thrombosis was present in 11 patients (6%). Fifty-five percent of patients experienced some form of toxicity following treatment; 21% developed grade 3 or 4 bilirubin toxicity. Post-chemoembolization response was seen in 31% and 64% of patients according to size and necrosis criteria, respectively. Median TTP was 7.9 months (95% confidence interval: 7.1, 9.4) but varied widely by stage. Median survival was significantly different between patients with BCLC stages A, B, and C disease (stage A, 40.0 months; B, 17.4 months; C, 6.3 months; P < .0001). CONCLUSION The determination of TTP and survival in patients with HCC is confounded by tumor biology and background cirrhosis; chemoembolization was shown to be a safe and effective therapy in patients with HCC.


Journal of Vascular and Interventional Radiology | 2011

Research Reporting Standards for Radioembolization of Hepatic Malignancies

Riad Salem; Robert J. Lewandowski; Vanessa L. Gates; Ravi Murthy; Steven C. Rose; Michael C. Soulen; Jean Francois H Geschwind; Laura Kulik; Yun Hwan Kim; Carlo Spreafico; Marco Maccauro; Lourens Bester; Daniel B. Brown; Robert K. Ryu; Daniel Y. Sze; William S. Rilling; Kent T. Sato; Bruno Sangro; José Ignacio Bilbao; Tobias F. Jakobs; Samer Ezziddin; Suyash Kulkarni; Aniruddha V. Kulkarni; David M. Liu; David Valenti; Philip Hilgard; Gerald Antoch; Stefan Müller; Hamad Alsuhaibani; Mary F. Mulcahy

Primary Liver Tumors Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver; its incidence is increasing worldwide. It ranks as the sixth most common tumor and third most common cause of cancer-related mortality (1,2). Primary liver tumors include HCC and intrahepatic cholangiocarcinoma. Surgical resection is preferred over transplantation and is considered potentially curative in patients with resectable HCC and normal liver function (3). Transplantation is considered the gold standard for patients with unresectable HCC and whose disease is within the Milan criteria (4). Resection and transplantation have limited roles, given advanced disease (chronic liver disease and/or tumor extent) at presentation and limited organ availability (5–7). Chemoembolization and radiofrequency ablation represent standard therapies in treating patients and serve as a bridge to transplantation in selected patients (8,9). Radioembolization has an emerging role in “bridging” patients within criteria by delaying tumor progression. It has also been shown to downstage disease beyond the Milan, to within, transplant criteria (10–12). A recent study has demonstrated that radioembolization leads to longer time-to-progression and better toxicity profile when compared with chemoembolization (13). Patients with macrovascular tumor involvement have also exhibited evidence of clinical benefit after radioembolization (14).


Journal of Hepatology | 2011

Role of the EASL, RECIST, and WHO response guidelines alone or in combination for hepatocellular carcinoma: radiologic-pathologic correlation.

Ahsun Riaz; Khairuddin Memon; Frank H. Miller; Paul Nikolaidis; Laura Kulik; Robert J. Lewandowski; Robert K. Ryu; Kent T. Sato; Vanessa L. Gates; Mary F. Mulcahy; Talia Baker; Ed Wang; Ramona Gupta; Ritu Nayar; Al B. Benson; Michael Abecassis; Reed A. Omary; Riad Salem

BACKGROUND & AIMS We sought to study receiver-operating characteristics (ROC) of the European Association for the Study of the Liver (EASL), Response Evaluation Criteria in Solid Tumors (RECIST), and World Health Organization (WHO) guidelines for assessing response following locoregional therapies individually and in various combinations. METHODS Eighty-one patients with hepatocellular carcinoma underwent liver explantation following locoregional therapies. Response was assessed using EASL, RECIST, and WHO. Kappa statistics were used to determine inter-method agreement. Uni/multivariate logistic regression analyses were performed to determine the variables predicting complete pathologic necrosis. Numerical values were assigned to the response classes: complete response=0, partial response=1, stable disease=2, and progressive disease=3. Various mathematical combinations of EASL and WHO were tested to calculate scores and their ROCs were studied using pathological examination of the explant as the gold standard. RESULTS Median times (95% CI) to the WHO, RECIST, and EASL responses were 5.3 (4-11.5), 5.6 (4-11.5), and 1.3months (1.2-1.5), respectively. Kappa coefficients for WHO/RECIST, WHO/EASL, and RECIST/EASL were 0.78, 0.28, and 0.31, respectively. EASL response demonstrated significant odds ratios for predicting complete pathologic necrosis on uni/multivariate analyses. Calculated areas under the ROC curves were: RECIST: 0.63, WHO: 0.68, EASL: 0.82, EASL+WHO: 0.82, EASL×WHO: 0.85, EASL+(2×WHO): 0.79 and (2×EASL)+WHO: 0.85. An EASL×WHO Score of ⩽1 had 90.2% sensitivity for predicting complete pathologic necrosis. CONCLUSIONS The product of WHO and EASL demonstrated better ROC than the individual guidelines for assessment of tumor response. EASL×WHO scoring system provides a simple and clinically applicable method of response assessment following locoregional therapies for hepatocellular carcinoma.


Gastroenterology | 2011

Radiographic Response to Locoregional Therapy in Hepatocellular Carcinoma Predicts Patient Survival Times

Khairuddin Memon; Laura Kulik; Robert J. Lewandowski; Ahsun Riaz; Robert K. Ryu; Kent T. Sato; Karen Marshall; Ramona Gupta; Paul Nikolaidis; Frank H. Miller; Vahid Yaghmai; Seanthan Senthilnathan; Talia Baker; Vanessa L. Gates; Michael Abecassis; Al B. Benson; Mary F. Mulcahy; Reed A. Omary; Riad Salem

BACKGROUND & AIMS It is not clear whether survival times of patients with hepatocellular carcinoma (HCC) are associated with their response to therapy. We analyzed the association between tumor response and survival times of patients with HCC who were treated with locoregional therapies (LRTs) (chemoembolization and radioembolization). METHODS Patients received LRTs over a 9-year period (n = 463). Patients with metastases, portal venous thrombosis, or who had received transplants were excluded; 159 patients with Child-Pugh B7 or lower were analyzed. Response (based on European Association for the Study of the Liver [EASL] and World Health Organization [WHO] criteria) was associated with survival times using the landmark, risk-of-death, and Mantel-Byar methodologies. In a subanalysis, survival times of responders were compared with those of patients with stable disease and progressive disease. RESULTS Based on 6-month data, in landmark analysis, responders survived longer than nonresponders (based on EASL but not WHO criteria: P = .002 and .0694). The risk of death was also lower for responders (based on EASL but not WHO criteria: P = .0463 and .707). Landmark analysis of 12-month data showed that responders survived longer than nonresponders (P < .0001 and .004, based on EASL and WHO criteria, respectively). The risk of death was lower for responders (P = .0132 and .010, based on EASL and WHO criteria, respectively). By the Mantel-Byar method, responders had longer survival than nonresponders, based on EASL criteria (P < .0001; P = .596 with WHO criteria). In the subanalysis, responders lived longer than patients with stable disease or progressive disease. CONCLUSIONS Radiographic response to LRTs predicts survival time. EASL criteria for response more consistently predicted survival times than WHO criteria. The goal of LRT should be to achieve a radiologic response, rather than to stabilize disease.

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Riad Salem

Northwestern University

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Laura Kulik

Northwestern University

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Kent T. Sato

Northwestern University

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Ahmed Gabr

Northwestern University

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Rehan Ali

Northwestern University

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