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Ixodes anatis is a species of endophilic (nidicolous) tick species parasitizing brown kiwi (Apteryx mantelli). Even though they are endemic to New Zealand like their host, very little is known about these ticks or their population dynamics and relationships with their hosts. We conducted a study from May 2013 to June 2014 to evaluate the effect of shelter location (one of three gullies), habitat (forest, scrub and pasture) and type (tree, soil and surface) on the abundance of the different life stages of I. anatis. In total, 12,172 ticks were collected from 63 shelters, which were sampled monthly for 11 months over the 14 month period. Un-engorged larvae predominated over other stages accounting for 87.2% of the samples collected. We found that location, habitat in which the shelters were located, and the type of shelter were significant predictors of I. anatis abundance. Tree shelters in forests had significantly higher tick abundance than those in scrub and pasture. Tree and soil shelters in general had significantly more ticks than surface shelters. Shelters located in Kauri Bush a drier site, had higher abundances than those in wetter sites. While some of these changes can be explained with the movement of the host, we believe more research needs to be done on the effect of shelters' microclimate on I. anatis' life cycle. [ABSTRACT FROM AUTHOR]

Purpose: The prognostic significance of renal pelvis vs ureteral upper urinary tract urothelial carcinoma tumor location is controversial. We assessed the prognostic significance of upper urinary tract urothelial carcinoma tumor location in a large, population based data set. Materials and Methods: Our analyses relied on 2,824 patients treated with nephroureterectomy for upper urinary tract urothelial carcinoma within 9 SEER registries between 1988 and 2004. Univariable and multivariable models tested the effect of tumor location on cancer specific mortality rates. Covariates consisted of age, race, SEER registry, gender, type of surgery (nephroureterectomy with vs without bladder cuff removal), pT stage, pN stage, grade and year of surgery. Results: Relative to ureteral tumors renal pelvis tumors were of higher stage (T3/T4 disease 38.4% vs 57.9%, p <0.001) and had a higher rate of lymph node metastases (6.0% vs 9.8%, p = 0.003) at nephroureterectomy. The respective 5-year cancer specific mortality-free survival estimates were 81.0% vs 75.5% (p = 0.007). However, after multivariable adjustment tumor location failed to reach independent predictor status of cancer specific mortality (p = 0.8). Conclusions: To our knowledge this is the largest cohort in which the impact of upper urinary tract urothelial carcinoma tumor location on cancer specific mortality was examined. At nephroureterectomy renal pelvis tumors had significantly more advanced T and N stages compared to ureteral tumors. However, after adjustment for stage, grade and other covariates tumor location did not independently predict cancer specific mortality. Thus, the biological behavior of renal pelvis vs ureteral tumors is the same after nephroureterectomy as long as stage, grade, and other patient and tumor characteristics are accounted for. [Copyright &y& Elsevier]

Purpose: A recent multi-institutional analysis of 995 patients treated for renal cell cancer questioned the relationship between tumor size and the synchronous metastasis rate. We revisited the hypothesis that metastatic potential is unrelated to tumor size. Materials and Methods: We tested the relationship between tumor size and synchronous metastasis in 22,204 patients with T1a and T1b renal cell cancer diagnosed and/or treated with nephrectomy for clear cell, papillary or chromophobe histological subtypes in 1 of 9 Surveillance, Epidemiology and End Results registries between 1988 and 2004. Results: In the study population the synchronous metastasis rate was 9.6%, including 5.6% vs 14.2% for T1a vs T1b. Stratification by 1 cm tumor size intervals revealed that the rate increased with increasing tumor size, that is 4.8% at 1.0 cm or less, 4.2% at 1.1 to 2.0 cm, 4.9% at 2.1 to 3.0 cm, 7.1% at 3.1 to 4.0 cm, 12.1% at 4.1 to 5.0 cm, 13.3% at 5.1 to 6.0 cm and 18.4% 6.1 to 7.0 cm (chi-square trend p <0.001). Cubic spline analysis showed that tumor size was virtually linearly related to the synchronous metastasis rate. Stratification by histological subtype in patients treated with nephrectomy revealed that clear cell renal cell cancer was most frequently associated with synchronous metastasis. Finally, tumor size was an independent predictor of synchronous metastasis in multivariate regression models adjusted for age, gender, histological subtype and year of diagnosis quartiles. Conclusions: Our study confirms that tumor size is an important determinant of the likelihood of synchronous metastasis in patients with T1a and T1b renal cell cancer. The synchronous metastasis rate directly increases with increasing tumor size. Even patients with small renal masses are at risk for synchronous metastasis and patients with clear cell renal cell cancer are at highest risk. [Copyright &y& Elsevier]

Purpose: Large variability exists in the rates of perioperative mortality after cystectomy. Contemporary estimates range from 0.7% to 5.6%. We tested several predictors of perioperative mortality and devised a model for individual perioperative mortality prediction. Materials and Methods: We relied on life tables to quantify 30, 60 and 90-day mortality rates according to age, gender, stage (localized vs regional), grade, type of surgery (partial vs radical cystectomy), year of cystectomy and histological bladder cancer subtype. We fitted univariable and multivariable logistic regression models using 5,510 patients diagnosed with bladder cancer and treated with partial or radical cystectomy within 4 SEER (Surveillance, Epidemiology, and End Results) registries between 1984 and 2004. We then externally validated the model on 5,471 similar patients from 5 other SEER registries. Results: At 30, 60 and 90 days the perioperative mortality rates were 1.1%, 2.4% and 3.9%, respectively. Age, stage and histological subtype represented statistically significant and independent predictors of 90-day mortality. The combined use of these 3 variables and of tumor grade resulted in the most accurate model (70.1%) for prediction of individual probability of 90-day mortality after cystectomy. Conclusions: The accuracy of our model could potentially be improved with the consideration of additional parameters such as surgical and hospital volume or comorbidity. While better models are being developed and tested we suggest the use of the current model in individual decision making and in informed consent considerations because it provides accurate predictions in 7 of 10 patients. [Copyright &y& Elsevier]

Objectives: To complement existing data with population-based cancer control outcomes that account for the effect of other-cause mortality (OCM). Cancer control rates are virtually equivalent between partial (PN) and radical nephrectomy (RN) for patients with T1aN0M0 renal cell carcinoma (RCC). To date, only 6 studies from centers of excellence examined cancer control rates after PN vs RN for T1aN0M0 RCC. OCM was unaccounted for in those studies, which may introduce a bias. We relied on the surveillance, epidemiology, and end results (SEER) database and assessed cancer-specific mortality (CSM) after either PN or RN for T1aN0M0 RCC, in competing-risks models., Methods: Between 1988 and 2004, the SEER-9 database identified 1622 PN (22.3%) and 5658 RN (77.7%) T1aN0M0 RCC. Competing-risks regression models, controlling for OCM and matched for age, year of surgery, tumor size, and Fuhrman grade, addressed the effect of nephrectomy type (PN vs RN) on CSM., Results: At 5 years, in a PN and RN matched-population controlling for OCM, CSM after PN and RN was respectively 1.8% vs 2.5% (P = .5). The CSM rates in this cohort for patients aged ≥ 70 years were respectively 1.0% and 3.4% (P = .7)., Conclusions: This competing-risks population-based analysis confirmed the CSM equivalence between PN and RN for T1aN0M0 RCC and showed virtually perfect CSM-free rates (97.5% or better) even in older patients., (Crown Copyright © 2010. Published by Elsevier Inc. All rights reserved.)

Study Type: Therapy (individual cohort)., Level of Evidence: 2b., Objective: To examine the temporal trends in stage and grade at presentation, as well as cancer-specific mortality (CSM) rates, in surgically treated patients with upper tract urothelial carcinoma (UTUC), as few population-based studies addressed contemporary cancer-control outcomes in patients with UTUC., Patients and Methods: Within the Surveillance, Epidemiology and End Results (SEER) database, we identified 4915 patients diagnosed with UTUC between 1983 and 2004, who had either a nephroureterectomy (NU) or a segmental ureterectomy (SU). Patients were divided into four groups according to the year-of-surgery quartiles. The chi-square test and the chi-square trend test were used for comparison of proportions and trends over time. Kaplan-Meier plots were used to graphically depict CSM rates. Multivariable Cox regression models were used to test the effect of the year-of-surgery quartiles on CSM. Covariates consisted of SEER stage, tumour grade, age, race, primary tumour site, type of surgery, and SEER registries., Results: Of 4915 assessable patients, 1316, 1328, 1146 and 1125 were, respectively, treated in 1983-1988, 1989-94, 1995-99 and 2000-2004. Of those, 4430 had a NU and 485 had a SU. The rates of non-localized stage and of grade III-IV disease at surgery increased, respectively, from 49.8% to 69.5% (P < 0.001) and 45.7 to 70.2% (P < 0.001) during the study period. CSM rates at 4 years after surgery reflected the temporal stage and grade differences, and increased from 18.2 to 23.9% (P = 0.03) between 1983-1988 and 2000-2004. In multivariable analyses, when stage and grade were taken into account, most contemporary patients showed more favourable CSM rates than their historic counterparts (hazard ratio 0.7, P = 0.02)., Conclusions: We report a stage and grade migration at NU or SU towards more aggressive disease among surgically treated patients between 1983 and 2004. Despite this observation, the CSM rates of contemporary patients have not worsened, which validates the role of NU and SU as effective treatments for UTUC.

Study Type: Prevalence (prospective cohort with good follow up)., Level of Evidence: 1a., Objective: To examine contemporary (1989-2004) trends in partial nephrectomy (PN) within the Surveillance, Epidemiology and End Results (SEER) database, as among other considerations, a survival benefit due to avoidance of surgically induced renal insufficiency distinguishes PN from radical nephrectomy (RN)., Patients and Methods: Diagnostic, stage and surgical codes of patients with T1-2N0M0 renal cell carcinoma treated with either PN or RN were assessed. Proportions, trends and multivariable logistic regression models tested the predictors of the use of PN., Results: Of 19 733 assessable patients, 2614 (13.2%) and 17 119 (86.8%), respectively, had PN or RN. The use of PN decreased with increasing tumour size, was more frequent in younger patients and increased with more contemporary years of surgery (all P < 0.001). Intriguingly, there was important geographical variability (P < 0.001), e.g. in the San Francisco-Oakland Metropolitan Area the absolute PN rate was 16.4%, vs 7.6% in New Mexico (P < 0.001). In multivariable analyses, tumour size, age, year of surgery, gender and SEER registries were independent predictors of PN use., Conclusion: Although as expected the rate of PN use increased over time, unexplained variability remained. For example, gender and SEER registries affected the likelihood of PN. These variables warrant further analyses to reduce unnecessary variability and to maximize PN use and its benefit.