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Alan Litwin

Publications and source records attributed to Alan Litwin.

6 recordsLinked to original sources
PubMed2006

Diagnosing regenerative nodular hyperplasia, the "great masquerader" of liver tumors.

Distinguishing benign tumors and pseudotumors of the liver from malignant tumors is a common clinical problem. Regenerative nodular hyperplasia (RNH) represents one of the more challenging pseudotumors to diagnose, because they can appear clinically indistinguishable from either a primary or a secondary liver malignancy. Even after comprehensive radiologic evaluation and image-guided percutaneous biopsy, the diagnosis of RNH can remain elusive. We reviewed the pathophysiology of RNH and present five cases illustrating the limitations of percutaneous biopsy and the utility of laparoscopic wedge biopsy in establishing the diagnosis. All patients underwent a complete workup that included percutaneous biopsy. Patients with a nondiagnostic percutaneous biopsy underwent a laparoscopic wedge biopsy or anatomical resection. H&E, vimentin, trichrome, and reticulin staining as well as CD34 immunostaining were performed. Five patients were diagnosed with RNH between May 2002 and April 2004. Three had focal nodular disease, whereas the other two had a diffuse multinodular presentation. Percutaneous biopsy definitively made the diagnosis in only one out of the five cases. Laparoscopic wedge biopsy was necessary to accurately make the diagnosis in three cases, whereas the fifth diagnosis was established after an anatomical resection. RNH is a unique pseudotumor of the liver that can present either as a solitary nodule or as a multinodular process. Percutaneous biopsy is associated with limitations in diagnosing RNH, and a more definitive surgical biopsy may be required. When RNH is considered, laparoscopic wedge biopsy is a safe and efficient way to obtain enough tissue to preserve the hepatic architecture required for diagnosis, while avoiding the morbidity of an unnecessary open resection.

Adult↗
PubMed2002

Oxaliplatin in combination with protracted-infusion fluorouracil and radiation: report of a clinical trial for patients with esophageal cancer.

PURPOSE: To identify a dose and schedule of oxaliplatin (OXP) to be safely administered in combination with protracted-infusion (PI) fluorouracil (5-FU) and external-beam radiation therapy (XRT) for patients with primary esophageal carcinoma (EC). PATIENTS AND METHODS: Eligibility included therapeutically naïve EC patients with clinical disease stages II, III, or IV. Initial doses and schedules for cycle 1 consisted of OXP 85 mg/m(2) on days 1, 15, and 29; PI 5-FU 180 mg/m(2) for 24 hours for 35 days; and XRT 1.8 Gy in 28 fractions starting on day 8. At completion of cycle 1, eligible patients could undergo an operation or begin cycle 2 without XRT. Postoperative patients were eligible for cycle 2. Stage IV patients were allowed three cycles in the absence of disease progression. OXP and 5-FU increases were based on dose-limiting toxicity (DLT) encountered in cohorts of three consecutive patients. RESULTS: Thirty-eight eligible patients received therapy: 22 noninvasively staged as IV and 16 noninvasively staged as II and III. Thirty-six patients completed cycle 1, 29 patients started cycle 2, and 24 patients completed cycle 2. The combined-modality therapy was well tolerated, but DLT prevented OXP and 5-FU escalation. No grade 4 hematologic toxicity was noted. Eleven grade 3 and two grade 4 clinical toxicities were noted in eight patients. After cycle 1, 29 patients (81%) had no cancer in the esophageal mucosa. Thirteen patients underwent an operation with intent to resect the esophagus; five patients (38%) exhibited pathologic complete responses. CONCLUSION: OXP 85 mg/m(2) on days 1, 15, and 29 administered with PI 5-FU and XRT is safe, tolerable, and seems effective against primary EC. The role of OXP in multimodality regimens against EC deserves further evaluation.

Adenocarcinoma↗
PubMedDate not supplied

Gadolinium-enhanced computed tomographic angiography: current status.

This article reviews the research to date, as well as our clinical experience from two institutions, on gadolinium-enhanced computed tomographic angiography (gCTA) for imaging the body. gCTA may be an appropriate examination for the small percentage of patients who would benefit from noninvasive vascular imaging, but who have contraindications to both iodinated contrast and magnetic resonance imaging. gCTA is more expensive than CTA with iodinated contrast, due to the dose of gadolinium administered, and gCTA has limitations compared with CTA with iodinated contrast, in that parenchymal organs are not optimally enhanced at doses of 0.5 mmol/kg or lower. However, in our experience, gCTA has been a very useful problem-solving examination in carefully selected patients. With the advent of 16-64 detector CT, in combination with bolus tracking, we believe that the overall dose of gadolinium needed for diagnostic CTA examinations, while relatively high, can be safely administered.

Angiography↗
PubMedDate not supplied

Gadopentetate dimeglumine is potentially an alternative contrast agent for three-dimensional computed tomography angiography with multidetector-row helical scanning.

OBJECTIVE: To demonstrate that gadopentetate dimeglumine is potentially an alternative contrast medium for computed tomographic angiography (CTA). METHODS: One 12.2-kg Beagle dog was studied as proof of principle; the cervical vessels of three adult human patients were imaged for presurgical planning of the neck. Gadopentetate dimeglumine, 0.5 mol/l (Berlex Laboratories, Wayne, NJ, U.S.A.), a LightSpeed QX/i CT (General Electric Medical Systems, Milwaukee, WI, U.S.A.), and an Ultra Sparc II (SUN Microsystems, Santa Clara, CA, U.S.A.) running Advantage Windows 3.1 (General Electric Medical Systems) were used. RESULTS: Sufficient enhancement for CTA of the thoracic aorta, cervical vessels, and abdominal vessels was produced in the experimental dog, and the cervical vessels were clearly defined in all three patients. CONCLUSION: In that subset of patients with contraindications to iodinated contrast medium and for whom magnetic resonance angiography is inappropriate, gadopentetate dimeglumine may be an alternative contrast medium for CTA.

Angiography↗