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Featured researches published by S. Sabir.


Modern Pathology | 2017

Concurrent fine needle aspirations and core needle biopsies: A comparative study of substrates for next-generation sequencing in solid organ malignancies

Sinchita Roy-Chowdhuri; Hui Chen; Rajesh R. Singh; Savitri Krishnamurthy; Keyur P. Patel; Mark Routbort; Jawad Manekia; Bedia A. Barkoh; Hui Yao; S. Sabir; Russell Broaddus; L. Jeffrey Medeiros; Gregg Staerkel; John A. Stewart; Rajyalakshmi Luthra

Minimally invasive procedures, such as fine needle aspiration and core needle biopsy, are commonly used for the diagnosis in solid organ malignancies. In the era of targeted therapy, it is crucial for molecular testing to be performed on these limited volume specimens. Although several recent studies have demonstrated the utility of small biopsy specimens for molecular testing, there remains debate as to whether core needle biopsy specimens are more reliable than fine needle aspiration for molecular studies. In this study, we reviewed concurrently acquired fine needle aspiration and core needle biopsy samples (n=24), and compared overall cellularity, tumor fraction, and the results of next-generation sequencing. All somatic mutations detected in core needle biopsy samples were also detected in fine needle aspiration samples. The estimated tumor fraction was significantly higher in fine needle aspiration smears than core needle biopsy samples (P=0.003), whereas the overall DNA yield from smears was significantly lower than that obtained from the core needle biopsy specimens (P=0.01). The normalized average amplicon coverage for the genes analyzed was significantly higher in cytology smears than paired core needle biopsy samples, with lower numbers of failed amplicons and higher overall mutation allelic frequencies seen in the former. We further evaluated 100 malignant fine needle aspiration and core needle biopsy samples, acquired concurrently, for overall cellularity and tumor fraction. Overall cellularity and tumor fraction of fine needle aspiration samples was significantly higher than concurrently acquired core needle biopsy samples (P<0.001). In conclusion, we show that fine needle aspiration samples frequently provide better cellularity, higher tumor fraction, and superior sequencing metrics than concurrently acquired core needle biopsy samples. Cytologic specimens, therefore, should be better integrated into routine molecular diagnostics workflow to maximize limited tissues for clinically relevant genomic testing.


Molecular Therapy | 2016

A Phase l Study of a Tumor-targeted Systemic Nanodelivery System, SGT-94, in Genitourinary Cancers

Arlene O. Siefker-Radtke; Xin Qiao Zhang; Charles C. Guo; Yu Shen; Kathleen F. Pirollo; S. Sabir; Chris P. Leung; Cindy Leong-Wu; Chi Ming Ling; Esther H. Chang; Randall E. Millikan; William F. Benedict

Gene therapy development has been limited by our inability to target multifocal cancer with systemic delivery. We developed a systemically administered, tumor-targeted liposomal nanodelivery complex (SGT-94) carrying a plasmid encoding RB94, a truncated form of the RB gene. In preclinical studies, RB94 showed marked cytotoxicity against tumor but not normal cells. SGT-94 was administered intravenously in a first-in-man study in metastatic genitourinary cancer. Minimal side effects were observed; dose-limiting toxicity (DLT) has not been reached in 11 evaluable patients. There was evidence of clinical activity at the 2.4 mg dose with one complete remission (CR) and one partial remission (PR). The patient in CR was retreated upon progression and had a second PR. Furthermore, there was tumor-specific targeting of the SGT-94 complex. One patient had wedge resections of two lung metastases which demonstrated RB94 expression at the DNA level by polymerase chain reaction (PCR) and at the protein level by Western blotting, with no RB94 present in normal contiguous lung. In conclusion, systemically delivered SGT-94 showed evidence of selective tumor targeting and was well tolerated with evidence of clinical activity. Additional studies are warranted to explore the activity of this drug as a single agent and in combination therapy.


Journal of Vascular and Interventional Radiology | 2014

Early Initiation of Enteral Feeding in Cancer Patients after Outpatient Percutaneous Fluoroscopy-Guided Gastrostomy Catheter Placement

S. Sabir; Ryan Armstrong; Linda S. Elting; Michael J. Wallace; Sanjay Gupta; A. Tam

PURPOSE To report the results of early enteral feeding in patients with cancer after outpatient placement of a percutaneous fluoroscopy-guided gastrostomy (PFG). MATERIALS AND METHODS From January 2008 through December 2008, 121 consecutive patients with cancer underwent outpatient placement of a PFG for nutrition. Of these patients, 118 patients met criteria for early feeding, and 113 were successfully fed early (after at least 3 hours). Of the patients fed early, 5 had insufficient follow-up for further analysis leaving 108 patients for outcomes analysis. After placement of the PFG, patients were put on low-wall suction via the PFG for 1 hour followed by feeding via the PFG at least 3 hours after placement. Follow-up evaluation was done the next business day. The medical records were reviewed for 30-day outcomes of early feeding, technical aspects of the procedures, and complications. RESULTS After placement of the PFG, 98% (118 of 121) of patients met criteria for early feeding, and 93% (113 of 121) of patients were successfully fed early. The median time between the end of the procedure and initiation of feeding was 4 hours (interquartile range, 3.7-4.4 h). The 30-day minor complication rate was 14% (15 of 108), and the 30-day major complication rate was 1% (1 of 108). No complications were directly attributable to early feeding. CONCLUSIONS Early initiation of tube feedings after outpatient placement of a PFG was well tolerated in patients with cancer and carried comparable risks to previously reported results using traditional delayed feeding protocols. Early feeding provided patients with prompt enteral nutrition and eliminated the need for routine hospital admission after the procedure.


PLOS ONE | 2017

Characteristics of percutaneous core biopsies adequate for next generation genomic sequencing

S. Sabir; Savitri Krishnamurthy; Sanjay Gupta; Gordon B. Mills; Wei Wei; Andrea Cortes; Kenna R. Mills Shaw; Rajyalakshmi Luthra; Michael J. Wallace

Purpose Determine the characteristics of percutaneous core biopsies that are adequate for a next generation sequencing (NGS) genomic panel. Materials and methods All patients undergoing percutaneous core biopsies in interventional radiology (IR) with samples evaluated for a 46-gene NGS panel during 1-year were included in this retrospective study. Patient and procedure variables were collected. An imaging-based likelihood of adequacy score incorporating targeting and sampling factors was assigned to each biopsied lesion. Univariate and multivariate logistic regression was performed. Results 153 patients were included (58.2% female, average age 59.5 years). The most common malignancy was lung cancer (40.5%), most common biopsied site was lung (36%), and average size of biopsied lesions was 3.8 cm (+/- 2.7). Adequacy for NGS was 69.9%. Univariate analysis showed higher likelihood of adequacy score (p = 0.004), primary malignancy type (p = 0.03), and absence of prior systemic therapy (p = 0.018) were associated with adequacy for NGS. Multivariate analysis showed higher adequacy for lesions with likelihood of adequacy scored 3 (high) versus lesions scored 1 (low) (OR, 7.82; p = 0.002). Melanoma lesions had higher adequacy for NGS versus breast cancer lesions (OR 9.5; p = 0.01). Absence of prior systemic therapy (OR, 6.1; p = 0.02) and systemic therapy 3 months before biopsy yielded greater adequacy for NGS. Lesions <3 cm had greater adequacy for NGS than larger lesions (OR 2.72, p = 0.02). Conclusion As targeted therapy becomes standard for more cancers, percutaneous biopsy specimens adequate for NGS genomic testing will be needed. An imaging-based likelihood of adequacy score assigned by IR physicians and other pre-procedure variables can help predict the likelihood of biopsy adequacy for NGS.


Journal of Functional Biomaterials | 2017

Endovascular Embolization by Transcatheter Delivery of Particles: Past, Present, and Future

Rahul A. Sheth; S. Sabir; Savitri Krishnamurthy; Reginald K. Avery; Yu Shrike Zhang; Ali Khademhosseini; Rahmi Oklu

Minimally invasive techniques to occlude flow within blood vessels, initially pioneered in the 1970s with autologous materials and subsequently advanced with increasingly sophisticated engineered biomaterials, are routinely performed for a variety of medical conditions. Contemporary interventional radiologists have at their disposal a wide armamentarium of occlusive agents to treat a range of disease processes through a small incision in the skin. In this review, we provide a historical perspective on endovascular embolization tools, summarize the current state-of-the-art, and highlight burgeoning technologies that promise to advance the field in the near future.


Journal of Bone and Joint Surgery, American Volume | 2017

Cryoablation of Bone Metastases from Renal Cell Carcinoma for Local Tumor Control

Carly S. Gardner; Joe E. Ensor; Kamran Ahrar; Steven Y. Huang; S. Sabir; Nizar M. Tannir; Valerae O. Lewis; Alda L. Tam

Background: Patients with bone metastases from renal cell carcinoma often are not surgical candidates and have a poor prognosis. There are limited data on the use of cryoablation as a locoregional therapy for bone metastases. Our objective was to assess the local tumor-control rate following cryoablation of bone metastases in the setting of renal cell carcinoma. Methods: We retrospectively reviewed the medical records of patients with metastatic renal cell carcinoma who underwent cryoablation for bone metastases between 2007 and 2014. We excluded patients if the intent of treatment was for pain palliation only, if cryoablation was performed without an attempt for complete tumor control (cytoreduction), or if the patient had no further follow-up beyond the cryoablation procedure. We recorded patient demographics, procedural variables, and complications. Cross-sectional imaging and clinical follow-up were reviewed to determine disease recurrence. The median overall survival and recurrence-free survival were determined using the Kaplan-Meier method. Results: Forty patients (30 male and 10 female) with 50 bone metastases were included for analysis. The mean patient age was 62 years (range, 47 to 82 years). The median follow-up was 35 months (95% confidence interval [CI], 22.7 to 74.4 months). Twenty-five (62.5%) of the 40 patients had oligometastatic disease, defined as ⩽5 metastases at the time of ablation. The mean tumor size was 3.4 ± 1.5 cm. Metastases in the pelvic region represented 68% of the treated tumors (34 of 50). The overall local tumor-control rate per lesion was 82% (41 of 50). Patients with oligometastatic disease experienced better local tumor control (96% [24 of 25]) compared with patients who had >5 metastases (53.3% [8 of 15]) (p = 0.001). The local tumor-control rate was better for lesions for which a larger mean difference between maximum ice-ball diameter and maximum lesion diameter was achieved (2.2 ± 0.9 cm for those without recurrence versus 1.35 ± 1.2 cm for those with recurrence; p = 0.005). There were 3 grade-3 complications and 1 grade-4 complication. Conclusions: Cryoablation can be effective for achieving local oncologic control in bone metastases from renal cell carcinoma and may represent a valuable alternative to surgical metastasectomy in select patients. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.


Journal of Vascular and Interventional Radiology | 2014

Celect filter penetration of aorta and lumbar artery.

John Pham; Steven Y. Huang; S. Sabir; Tam T.T. Huynh; Michael J. Wallace

images showed an intraluminal bronchial mass with a large extrabronchial solitary component, raising suspicion of a carcinoid tumor. Many treatment regimens are available for management of a carcinoid crisis. These consist of blocking the release of the mediators from tumor tissue by administering somatostatin analogues such as octreotide (2,3). In the acute situation, 100–500 mg of octreotide can be


Biomedical Optics Express | 2018

Investigation of tissue cellularity at the tip of the core biopsy needle with optical coherence tomography

Nicusor Iftimia; Jesung Park; Gopi Maguluri; Savitri Krishnamurthy; Amanda McWatters; S. Sabir

We report the development and the pre-clinical testing of a new technology based on optical coherence tomography (OCT) for investigating tissue composition at the tip of the core biopsy needle. While ultrasound, computed tomography, and magnetic resonance imaging are routinely used to guide needle placement within a tumor, they still do not provide the resolution needed to investigate tissue cellularity (ratio between viable tumor and benign stroma) at the needle tip prior to taking a biopsy core. High resolution OCT imaging, however, can be used to investigate tissue morphology at the micron scale, and thus to determine if the biopsy core would likely have the expected composition. Therefore, we implemented this capability within a custom-made biopsy gun and evaluated its capability for a correct estimation of tumor tissue cellularity. A pilot study on a rabbit model of soft tissue cancer has shown the capability of this technique to provide correct evaluation of tumor tissue cellularity in over 85% of the cases. These initial results indicate the potential benefit of the OCT-based approach for improving the success of the core biopsy procedures.


Oncologist | 2017

Portomesenteric Venous Stenting for Palliation of Ascites and Variceal Bleeding Caused by Prehepatic Portal Hypertension

Rahul A. Sheth; S. Sabir; Philip Parmet; Roshon Amin; Joshua Kuban; Steven Y. Huang; Armeen Mahvash; David R. Fogelman; Milind Javle; Michael J. Wallace

BACKGROUND The purpose of this study was to evaluate percutaneous transhepatic portal vein stenting (PVS) for palliation of refractory ascites and/or variceal bleeding caused by extrahepatic portomesenteric venous stenosis in patients with pancreaticobiliary cancer. MATERIALS AND METHODS A single-institution, retrospective review of patients who underwent PVS between January 2007 and July 2015 was performed. A total of 38 patients were identified, of whom 28 met the inclusion criterion of PVS performed primarily for refractory ascites or variceal bleeding. In addition to technical success and overall survival, clinical success was measured by fraction of remaining life palliated. The palliative effect of PVS was also quantified by measuring changes in liver and ascites volumes after the procedure. RESULTS Technical success was 93% (26/28). Stent deployment involved more than one portomesenteric vessel in most patients (20/26). The cumulative probability of symptom recurrence at 6, 12, 18, and 24 months was 12%, 16%, 26%, and 40%, respectively. There was a significant difference (p < .001) in the probability of symptom recurrence, recurrence of abdominal ascites, and increase in liver volume between patients whose stents remained patent and those whose stents demonstrated partial or complete occlusion. The mean fraction of remaining life palliated was 87%. All but two patients were found to have improvement in clinical symptoms for the majority of their lives after the procedure. There were no major or minor complications. CONCLUSION As a low-risk procedure with a high clinical success rate, PVS can play a substantial role in improving quality of life in patients with portomesenteric stenoses. IMPLICATIONS FOR PRACTICE Portomesenteric venous stenosis is a challenging complication of pancreaticobiliary malignancy. Portomesenteric stenoses can lead to esophageal, gastric, and mesenteric variceal bleeding, as well as abdominal ascites. The purpose of this study was to evaluate the safety and efficacy of portal vein stenting (PVS) in patients with cancer who have symptomatic portal hypertension caused by portomesenteric venous compression. As a low-risk procedure with a high clinical success rate, PVS can play a substantial role in improving quality of life in patients with portomesenteric stenoses.


Journal of Thrombosis and Thrombolysis | 2017

Development of a predictive model for 6 month survival in patients with venous thromboembolism and solid malignancy requiring IVC filter placement

Steven Y. Huang; Bruno C. Odisio; S. Sabir; Joe E. Ensor; A Niekamp; Tam T.T. Huynh; Michael Kroll; Sanjay Gupta

Purpose: Our purpose was to develop a predictive model for short-term survival (i.e. <6 months) following inferior vena cava filter placement in patients with venous thromboembolism (VTE) and solid malignancy. Methods: Clinical and laboratory parameters were retrospectively reviewed for patients with solid malignancy who received a filter between January 2009 and December 2011 at a tertiary care cancer center. Multivariate Cox proportional hazards modeling was used to assess variables associated with 6 month survival following filter placement in patients with VTE and solid malignancy. Significant variables were used to generate a predictive model. Results: 397 patients with solid malignancy received a filter during the study period. Three variables were associated with 6 month survival: (1) serum albumin [hazard ratio (HR) 0.496, P < 0.0001], (2) recent or planned surgery (<30 days) (HR 0.409, P < 0.0001), (3) TNM staging (stage 1 or 2 vs. stage 4, HR 0.177, P = 0.0001; stage 3 vs. stage 4, HR 0.367, P = 0.0002). These variables were used to develop a predictive model to estimate 6 month survival with an area under the receiver operating characteristic curve of 0.815, sensitivity of 0.782, and specificity of 0.715. Conclusions: Six month survival in patients with VTE and solid malignancy requiring filter placement can be predicted from three patient variables. Our predictive model could be used to help physicians decide whether a permanent or retrievable filter may be more appropriate as well as to assess the risks and benefits for filter retrieval within the context of survival longevity in patients with cancer.

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Kamran Ahrar

University of Texas MD Anderson Cancer Center

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Sanjay Gupta

University of Texas MD Anderson Cancer Center

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Steven Y. Huang

University of Texas MD Anderson Cancer Center

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A. Tam

University of Texas MD Anderson Cancer Center

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Michael J. Wallace

University of Texas MD Anderson Cancer Center

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Rahul A. Sheth

University of Texas MD Anderson Cancer Center

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Armeen Mahvash

University of Texas MD Anderson Cancer Center

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Bruno C. Odisio

University of Texas MD Anderson Cancer Center

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Joe E. Ensor

University of Texas MD Anderson Cancer Center

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Surena F. Matin

University of Texas MD Anderson Cancer Center

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