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Martin I Resnick

Publications and source records attributed to Martin I Resnick.

At least 37 records · Page 2Linked to original sources
PubMed2004

Migration of implanted free radioactive seeds for adenocarcinoma of the prostate using a Mick applicator.

PURPOSE: This study investigates the rate of free seed migration and associated seed-related sequelae after using a radioimmunoguided Mick applicator technique to place radioactive seeds within the prostate. METHODS AND MATERIALS: Between December 1998 and September 2002, 120 patients diagnosed with prostate cancer underwent interstitial transperineal prostate brachytherapy with free (125)I or (103)Pd seeds positioned using a radioimmunoguided Mick applicator technique. Orthogonal pelvic and chest radiographs were obtained postimplant (Day 0) and at a second follow-up visit to determine the rate of radioactive seed embolization. RESULTS: On the day of implant (Day 0), 7 (6%) of the 120 men demonstrated single pulmonary seed emboli; none of these seeds migrated subsequently. During follow-up, 87 (72.5%) men had a total of 249 (2.0%) out of 12,524 seeds implanted migrate. Sixty-eight (0.55%) of the implanted seeds migrated to the lungs, an incidence common among brachytherapy techniques utilizing free or vicryl-laden radioactive seeds. No clinical symptoms or adverse sequelae from seed emboli have been reported. CONCLUSIONS: The rate of seed emboli to the pulmonary vessels or to other tissue localities resulting from a radioimmunoguided Mick applicator technique does not appear to be markedly different from the reported rate seen with other free seed techniques.

Adenocarcinoma↗
PubMed2004

The impact of osteoporosis in men treated for prostate cancer.

Prostate cancer patients are at significant risk for SREs, with up to 50% of androgen-insensitive patients experiencing an SRE at 24 months. The risk increases with the duration and type of cancer treatment. SREs decrease HRQOL, increase the cost of care, and are associated negatively with overall survival. Screening men at greatest risk (slender white men and men with hormone refractory disease or metastatic disease) with BMD measurements, and initiating empiric therapy (vitamin D3, calcium, parenteral estrogens, bisphosphates) may be warranted.

Aged↗
PubMed2004

Medical management of calcium oxalate urolithiasis.

Dietary modifications and medical therapy can reduce the risk of urinary stone formation. Using the described stepwise approach, the medical management of stone disease should become a less daunting task for physicians. Unfortunately, the optimal medical and dietary management of urolithiasis remains uncertain and recurrent stone disease remains a significant cause of morbidity. Approaches to diagnosis and medical management have improved considerably in the last decade and it is hoped that well-designed studies in the near future will help further optimize management.

Calcium Oxalate↗
PubMed2004

Minipump induced hyperoxaluria and crystal deposition in rats: a model for calcium oxalate urolithiasis.

PURPOSE: Unraveling the mechanisms leading to clinically active calcium oxalate (CaOx) stone disease and the development of effective medical therapies to treat it have been hampered by the lack of appropriate animal models. To address this problem we developed a model of hyperoxaluria and calcium oxalate crystal deposition by implanting osmotic minipumps subcutaneously into male rats, that is minipump induced hyperoxaluria and crystal deposition in rats. MATERIALS AND METHODS: Male Harlan-Sprague Dawley rats (225 to 290 gm) were implanted subcutaneously with 1-week 2 ml osmotic minipumps containing 1.5 M potassium oxalate (360 microM KOx/24 hours, [KOx-trt], 11) or phosphate buffered saline (PBS-trt, 9) on days 1 and 7. The 24-hour urine collections were performed on days 0, 4, 7, 11 and 14. Data were analyzed by ANOVA and Tukey's HSD. Urinary crystals were analyzed by light microscopy. Kidneys were harvested on day 14 and processed for light and polarizing microscopy, and RNA analysis.RESULTS Mean overall creatinine excretion +/- SEM (PBS-trt 107 +/- 7 and KOx-trt 123 +/- 6 microM/24 hours, p >0.07) and day 14 serum creatinine (PBS-trt 83 +/- 4 and KOx-trt 83 +/- 5 microM, p >or=0.9) were similar in the 2 treatment groups. Overall urinary volume (PBS-trt 11.3 +/- 0.8 and KOx-trt 18.0 +/- 1.5 ml/24 hours, p <or=0.001) and oxalate (OX) excretion (PBS-trt 9.2 +/- 0.6 and KOx-trt 44 +/- 4.2 microM/24 hours, p <or=0.001) were higher in KOx-trt vs PBS-trt rats. In KOx-trt rats OX excretion on day 0 was significantly less than on any day after implantation (p <or=0.01). All KOx-trt rats excreted calcium oxalate dihydrate crystals by day 4 and had intrarenal deposits of birefringent crystals by day 14. Overall the morphology of kidneys of OX rats was normal, although localized regions of inflammation and tubular debris were occasionally observed. Reverse transcriptase-polymerase chain reaction and Northern blot analysis revealed that the expression of 3 distress molecules tumor necrosis factor receptor, osteopontin and kidney injury molecule were up-regulated in KOx-trt kidneys. CONCLUSIONS: The model of minipump induced hyperoxaluria and crystal deposition in rats reliably induces hyperoxaluria, CaOx crystalluria and CaOx crystal deposition. These characteristics make it an appropriate model for investigations of the effects of OX on renal physiology as well as investigating the efficacy of new therapeutics.

Animals↗
PubMed2004

Survival of patients with hormone refractory prostate cancer in the prostate specific antigen era.

PURPOSE: The historically reported 12 to 18-month duration of survival of patients with hormone refractory prostate cancer is not consistent with current clinical experience. Furthermore, to our knowledge patient survival after serum prostate specific antigen (PSA) progressively increases from a nadir despite castrate testosterone has not been previously reported. For this reason we studied overall survival and the clinical variables that influence survival in patients with hormone refractory prostate cancer. MATERIALS AND METHODS: The study focused on 254 patients with prostate cancer on androgen deprivation therapy. Hormone refractory prostate cancer was defined as the first in a series of PSA elevations despite castrate levels of testosterone. The duration of survival in the hormone refractory phase was calculated from the date of the first PSA elevation to the date of death. RESULTS: Median survival after hormone refractory prostate cancer developed in patients initially staged with and without skeletal metastasis was 40 and 68 months, respectively. Six of more than 25 input variables were retained as significant in the final Cox model. Variables associated with longer survival were lower nadir PSA, younger age, higher pretreatment testosterone, no history of obstructive uropathy, no history of tobacco use (past or current) and lower alkaline phosphatase. CONCLUSIONS: Historical reports of survival in hormone refractory prostate cancer underestimate current survival observations. The likely explanations of this observation include delayed enrollment in clinical trials from which most survival data are derived, PSA lead time in staging and improved supportive care. Models predicting survival in patients with hormone refractory prostate cancer should consider multiple variables.

Aged↗
PubMed2004

Benign intrascrotal lesions.

PURPOSE: We summarize important clinical, pathological and diagnostic features of benign intrascrotal lesions, including paratesticular lesions (adenomatoid tumors, fibrous pseudotumors, cystadenomas, spermatoceles, hydroceles, varicoceles and hernias) and intratesticular lesions (tunica albuginea cysts, testicular simple cysts, epidermoid cysts, cystic ectasia of the rete testis, intratesticular varicocele, adrenal rest tumors and splenogonadal fusion). This review provides the reader with a better understanding of benign lesions that occur in the scrotum. MATERIALS AND METHODS: A directed MEDLINE literature review of benign scrotal lesions and of each individual lesion was performed. This information was enhanced with relevant information from select journals and texts. Particular emphasis was placed on clinical, pathological and diagnostic features. RESULTS: Intrascrotal lesions continue to provide a diagnostic challenge for physicians. A diagnosis can be made with a thorough history, physical examination and understanding of the pathophysiological processes of the structures contained within the scrotum. Lesions that are suspicious for malignancy should prompt urological consultation and radiological imaging. Ultrasound aids in the diagnosis in instances of uncertainty. Ultimately surgery may be necessary to make a histological diagnosis. CONCLUSIONS: Clinical assessment, physical examination and an understanding of benign intrascrotal processes are key to making a diagnosis. Ultrasound has an important role and adds essential information. If surgery is necessary and a benign process is recognized, a testis sparing procedure should be performed.

Adenomatoid Tumor↗
PubMed2004

Association of tobacco use with hormone refractory disease and survival of patients with prostate cancer.

PURPOSE: We identified time to the development of hormone refractory prostate cancer (HRPC) and survival in men with advanced prostate cancer and examined any association with cigarette smoking history. MATERIALS AND METHODS: The study design was retrospective. A complete tobacco history was obtained in 222 patients with advanced prostate cancer. HRPC was diagnosed in 133 of these 222 patients and death occurred in 77. Standard statistical methods and software were used to analyze these data. RESULTS: Median time to HRPC was 11, 23 and 35 months in patients with a current, former or never smoked tobacco history (p = 0.00001). Median overall survival time on androgen ablative therapy was 38, 47 and 60 months in patients with a current, former or never smoked tobacco history, respectively (p = 0.00001). CONCLUSIONS: Tobacco use independently correlates with time to HRPC and survival in a dose dependent manner in patients with advanced prostate cancer on androgen deprivation therapy.

Adenocarcinoma↗
PubMed2004

Flank incision.

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Humans↗
PubMed2004

Microarray analysis of changes in renal phenotype in the ethylene glycol rat model of urolithiasis: potential and pitfalls.

OBJECTIVES: To investigate, in an initial study, the use of microarray analysis (MA) to develop an information base for urolithiasis. MA enables the screening of thousands of genes simultaneously making it the technique of choice for situations where the results are known, but the underlying mechanisms are not. Little is known about the pathological changes occurring in the kidney during urolithiasis and this has severely hampered efforts to develop effective therapeutics. MATERIALS AND METHODS: Male rats were treated with 0.75% ethylene glycol for 2, 4 or 8 weeks; after death the kidneys were processed for RNA isolation and MA, conducted using a rat-based chip (one kidney/chip) and the results confirmed by reverse transcription-polymerase chain reaction (RT-PCR, 21 probe sets; control, four rats; treated, five rats). Targets were defined as different by the software if the fold change (FC) was >or= 2, and sorted into functional categories using a data-mining tool. The repeatability of MA was investigated by subjecting the 4-week samples to MA in two independent runs. RESULTS: The results for targets with a FC of >or= 2 were plotted (y = 1.01x - 0.75; r(2) 0.84). Comparing the results obtained by RT-PCR and MA showed a good qualitative correlation for those targets having a FC of >or= 5 as determined by MA. Changes in the expression of genes associated with tubule function and regulation, oxidative damage, and inflammation were the most common in the functional categories. Changes in the expression of tubule-specific markers indicated that there was damage to the proximal (gamma-adducin, organic anion and cation transporters, sodium-hydrogen exchange protein-isoform 3) and distal tubules (gamma-adducin, kallikrein) at 2 and 4 weeks. Increased expression of mitochondrial uncoupling protein indicated that there were changes to the mitochondria and oxidative stress at 2 and 4 weeks. CONCLUSION: This study shows the power of MA as an exploratory technique, and changes in the expression of several physiologically important genes whose expression has not previously been reported to be affected by hyperoxaluria or calcium oxalate crystalluria.

Animals↗
PubMed2004

Phase II clinical trial of interactive MR imaging-guided interstitial radiofrequency thermal ablation of primary kidney tumors: initial experience.

PURPOSE: To perform a phase II clinical trial to evaluate efficacy and safety of interactive magnetic resonance (MR) imaging-guided radiofrequency (RF) interstitial thermal ablation (ITA) of primary renal tumors. MATERIALS AND METHODS: Ten male patients (age range, 25-83 years) with peripheral renal cell carcinoma and contraindications to surgery were treated with percutaneous RF ITA entirely guided and monitored with a 0.2-T MR imaging unit. By using a 200-W RF ablation system and custom-fabricated MR imaging-compatible cool-tip electrodes, pulsed RF current was applied for single or multiple ablation cycle(s) of 12-15 minutes until the entire tumor was replaced by an enlarging zone of low signal intensity on T2-weighted and/or short inversion time inversion-recovery images acquired intermittently during the procedure. Kidney MR images were acquired before, immediately after, and 2 weeks after ablation and then every 3 months for 1 year and every 6 months thereafter. Intra- and postprocedural complications were assessed with clinical evaluation of patients for pain and hemodynamic instability and evaluation of MR images for evidence of hemorrhage or other unexpected findings. Follow-up images were assessed for delayed complications such as renal ischemia, infarct, urinoma, or tumor recurrence. RESULTS: Treated tumors ranged between 0.63 and 16.90 mL in volume and 1.0 and 3.6 cm in maximum diameter. Successful RF electrode insertion and/or repositioning into the renal mass was achieved in all cases with direct MR "fluoroscopic" guidance. Thirty ablation cycles were conducted at 21 electrode positions in the 10 procedures, and complete ablation, as defined with MR imaging, was achieved in all cases by the end of the procedure. Apart from two small self-limited perirenal hematomas, no intra- or postprocedural complications were observed. No delayed complications or tumor recurrence occurred during a mean follow-up period of 25 months +/- 9.4 (standard deviation). CONCLUSION: Although these results are preliminary, interactive MR imaging-guided RF ITA for treatment of primary renal tumors has a high success rate.

Adult↗
PubMed2003

Combination conformal radiotherapy and radioimmunoguided transperineal 103Pd implantation for patients with intermediate and unfavorable risk prostate adenocarcinoma.

PURPOSE: To report outcomes for prostate cancer patients treated with external beam radiation therapy (EBRT) and permanent prostate brachytherapy utilizing radioimmunoguided targeting of biological tumor volumes (BTVs). METHODS AND MATERIALS: Between February 1997 and October 2001, 66 patients with intermediate- to high-risk prostate cancer underwent EBRT and ProstaScint-guided transperineal brachytherapy. Thirty patients received neoadjuvant hormonal manipulation, while 36 patients did not. Median patient age was 66 years (range, 49-78 years). The median follow-up was 41 months (range, 24-78 months). No patients were lost to follow-up. Risk factors (RF) used for risk stratification included PSA >10 ng/ml (35 patients), Stage T2b or greater (22 patients), and Gleason score > or = 7 (55 patients). Results for biochemical disease free survival (bDFS) were reported using the ASTRO consensus definition for biochemical failure, PSA < or = 1.0 ng/mL or PSA< or = 0.5 ng/mL. Survival was estimated by the Kaplan-Meier method. RESULTS: Five-year overall survival was 93.1% and 5-year bDFS by the ASTRO definition was 89.3% with a median follow up of 41 months. Patients with intermediate- (1 RF) and high-risk (2-3 RF) prostate cancer exhibited 5-year ASTRO-defined bDFS of 100% and 81.9%, respectively. There was no significant difference in bDFS between the patients treated with or without hormone therapy (HT). The 5-year ASTRO-defined bDFS was 89.8% for the 30 patients treated with HT and 88.9% for the 36 patients who did not receive HT (p = 0.843). For the patients without HT the median PSA nadir was 0.11 ng/mL. The median time to nadir was 23 months (range, 6-66 months). CONCLUSIONS: With limited follow-up, the results of EBRT plus radioimmunoguided brachytherapy for intermediate- to high-risk prostate cancer appear favorable. The addition of HT did not appear to affect bDFS significantly, but interpretation is confounded by possible selection bias and the limited power of this study.

Adenocarcinoma↗
PubMed2003

Renal radiofrequency ablation: clinical status 2003.

PURPOSE OF REVIEW: Energy-based tumor ablative techniques are under development for the minimally invasive treatment of renal cell carcinoma. Radiofrequency ablation has recently entered phase II clinical trials for the treatment of small renal tumors. The authors review the status of these clinical trials. RECENT FINDINGS: Radiofrequency ablation has shown reproducible tumor destruction in both animal models and recent clinical trials. Radiographic follow-up of radiofrequency ablated small renal tumors demonstrates little or no residual contrast enhancement depending on tumor size, location within the kidney, and mode of delivering radiofrequency energy. Pathologic evaluation of ablated tumors shows more variability in outcome, with many tumors demonstrating small areas of viable residual tumor. SUMMARY: Radiofrequency ablation shows promise for the minimally invasive treatment of small renal tumors but will remain experimental until the resolution of certain technical issues.

Carcinoma, Renal Cell↗