Investigating the role of organic carbon amendments and microbial denitrification gene abundance in nitrogen removal from experimental agricultural drainage ditches with low-grade weirs.

Low-grade weirs placed within agricultural drainage ditches in the Lower Mississippi Alluvial Valley can be used as a management practice to enhance nitrogen removal. The addition of organic carbon amendments within ditches that contain weirs could further increase nitrogen removal. Through repeated trials, changes in NO 3 - -N concentration between inflow and outflow were variable in the ditch without weirs, while only decreases in concentration were observed in ditches with weirs. Significant differences in NO 3 - -N concentrations were observed between treatments, with greater removal of NO 3 - -N observed in dissolved organic carbon treatments compared to control and particulate organic carbon treatments. At medium- and high-flow rates, respectively, dissolved organic carbon treatments resulted in greater NO 3 - -N concentration decreases of 31.6% and 27.1% compared to 19% and 11.6% in particulate organic carbon treatments and 18.6% and 17.2% in control treatments. Significant effects of weirs and sampling date on nirS, nirK, nosZ, and 16S rRNA gene abundances were observed. Observed increases in NO 3 - -N removal with organic carbon amendments, provides support for continued investigation on improving the efficacy of organic carbon amendments as a best management practice for NO 3 - -N removal in agricultural drainage ditches. PRACTITIONER POINTS: Dissolved organic carbon amendments increased nitrate-nitrogen removal. Only decreases in nitrate-nitrogen concentration were observed in ditches with weirs. Increasing flow rate did not affect nitrate-nitrogen removal. Abundance of denitrification-performing microbes likely did not affect N removal. Lack of anaerobic soil conditions and short residence time reduced nitrate-N removal.

Effects of Low-Grade Weirs on Soil Microbial Communities in Agricultural Drainage Ditches.

Agricultural fertilizer application throughout the Mississippi River basin has been identified as a major source of N pollution to the Gulf of Mexico. Using best management practices, such as low-grade weirs, has been identified as a potential solution to mitigate nutrient loads in agricultural runoff. This study assessed impacts of weir implementation in four agricultural drainage ditches (three with weirs and one control site) in the Mississippi Delta. Soil samples collected from field locations in spring 2013 were analyzed for denitrifier abundance using genes (16s ribosomal RNA [rRNA] genes, , , and ) via quantitative polymerase chain reaction (qPCR), microbial community profiles via terminal-restriction fragment length polymorphism (T-RFLP) of 16s rRNA genes, soil parameters (C, N, and moisture), and vegetation presence at sample locations. Gene quantification was successful, except for , which was found below detection limits (5000 gene copies g soil). Distance from weirs was negatively correlated with 16S rRNA genes and soil moisture, and soil moisture was positively correlated with 16s rRNA and S gene abundance. Results of empirical Bayesian kriging did not exhibit obvious patterns of microbial diversity in relation to weir proximity. Preliminary assessment of seasonal trends showed genes 16s rRNA and , soil N, and mean T-RF values to be greater in fall than in spring. Results highlight that weirs had no direct impact on microbial diversity or denitrification functional gene abundance. Correlations between microbial measures and environmental parameters suggest that adequate management of N runoff from agricultural landscapes will require ecological engineering beyond weirs to optimize N mitigation.

Management Practices Used in Agricultural Drainage Ditches to Reduce Gulf of Mexico Hypoxia.

Agricultural non-point sources of nutrients and sediments have caused eutrophication and other water quality issues in aquatic and marine ecosystems, such as the annual occurrence of hypoxia in the Gulf of Mexico. Management practices have been implemented adjacent to and in agricultural drainage ditches to promote their wetland characteristics and functions, including reduction of nitrogen, phosphorus, and sediment losses downstream. This review: (1) summarized studies examining changes in nutrient and total suspended solid concentrations and loads associated with management practices in drainage ditches (i.e., riser and slotted pipes, two-stage ditches, vegetated ditches, low-grade weirs, and organic carbon amendments) with emphasis on the Lower Mississippi Alluvial Valley, (2) quantified management system effects on nutrient and total suspended solid concentrations and loads and, (3) identified information gaps regarding water quality associated with these management practices and research needs in this area. In general, management practices used in drainage ditches at times reduced losses of total suspended solids, N, and P. However, management practices were often ineffective during storm events that were uncommon and intense in duration and volume, although these types of events could increase in frequency and intensity with climate change. Studies on combined effects of management practices on drainage ditch water quality, along with research towards improved nutrient and sediment reduction efficiency during intense storm events are urgently needed.

Mitigation of atrazine, S-metolachlor, and diazinon using common emergent aquatic vegetation.

By the year 2050, the population of the United States is expected to reach over 418 million, while the global population will reach 9.6 billion. To provide safe food and fiber, agriculture must balance pesticide usage against impacts on natural resources. Challenges arise when storms cause runoff to be transported to aquatic receiving systems. Vegetated systems such as drainage ditches and constructed wetlands have been proposed as management practices to alleviate pesticide runoff. Twelve experimental mesocosms (1.3×0.71×0.61m) were filled with sediment and planted with a monoculture of one of three wetland plant species (Typha latifolia, Leersia oryzoides, and Sparganium americanum). Three mesocosms remained unvegetated to serve as controls. All mesocosms were amended with 9.2±0.8µg/L, 12±0.4µg/L, and 3.1±0.2µg/L of atrazine, metolachlor, and diazinon, respectively, over a 4hr hydraulic retention time to simulate storm runoff. Following the 4hr amendment, non-amended water was flushed through mesocosms for an additional 4hr. Outflow water samples were taken hourly from pre-amendment through 8hr, and again at 12, 24, 48, 72, and 168hr post-amendment. L. oryzoides and T. latifolia had mean atrazine, metolachlor, and diazinon retentions from 51%-55% for the first 4hr of the experiment. Aside from S. americanum and atrazine (25% retention), unvegetated controls had the lowest pesticide retention (17%-28%) of all compared mesocosms. While native aquatic vegetation shows promise for mitigation of pesticide runoff, further studies increasing the hydraulic retention time for improved efficiency should be examined.

Investigation of denitrifying microbial communities within an agricultural drainage system fitted with low-grade weirs.

Enhancing wetland characteristics in agricultural drainage ditches with the use of low-grade weirs, has been identified as a best management practice (BMP) to mitigate nutrient runoff from agriculture landscapes. A major objective of utilizing low-grade weirs as a BMP includes fostering environments suitable for the biogeochemical removal of nitrogen via denitrification. This study examined the spatial resolution of microbial communities involved in denitrification in agricultural drainage systems fitted with low-grade weirs. Appropriate sampling scales of microbial communities were investigated using 16S rRNA and denitrification functional genes nosZ, nirS, and nirK via quantitative polymerase chain reaction (qPCR) and terminal-restriction fragment length polymorphism (T-RFLP) analysis. Genes 16S rRNA, nosZ, and nirS were all successfully detected in soil samples, while nirK was below the detection limit throughout the study. Utilizing a combination of three sampling regimes (management, reach, catchment) was found to be effective in capturing microbial community patterns, as ANOVA results revealed nosZ gene abundance was significantly greater at the management rather than reach scale (p = 0.045; F = 3.311), although, no significant differences were observed in 16S rRNA or nirS between sampling scales (p > 0.05). A Pearson correlation matrix confirmed that 16S rRNA and nosZ gene abundances were positively correlated with soil carbon (C), nitrogen (N), and moisture, while nirS abundance was only positively correlated with soil C and soil moisture. This highlights the potential for wetland-like characteristics to be recovered in agricultural drainage systems, as weir proximity is observed to enhance soil moisture and conditions for N remediation. This study provides the basis for additional investigations of these unique environments in the Mississippi Alluvial Valley and a starting point for adaptive management to enhance agricultural drainage systems for microbial communities towards nutrient remediation goals.

Mitigating agrichemicals from an artificial runoff event using a managed riverine wetland.

We examined the mitigation efficiency of a managed riverine wetland amended with a mixture of suspended sediment, two nutrients (nitrogen and phosphorus), and three pesticides (atrazine, metolachlor, and permethrin) during a simulated agricultural runoff event. Hydrologic management of the 500 m-long, 25 m-wide riverine wetland was done by adding weirs at both ends. The agrichemical mixture was amended to the wetland at the upstream weir simulating a four-hour, ~1cm rainfall event from a 16ha agricultural field. Water samples (1L) were collected every 30 min within the first 4h, then every 4h until 48 h, and again on days 5, 7, 14, 21, and 28 post-amendment at distances of 0m, 10 m, 40 m, 300 m and 500 m from the amendment point within the wetland for suspended solids, nutrient, and pesticide analyses. Peak sediment, nutrient, and pesticide concentrations occurred within 3 h of amendment at 0m, 10 m, 40 m, and 300 m downstream and showed rapid attenuation of agrichemicals from the water column with 79-98%, 42-98%, and 63-98% decrease in concentrations of sediments, nutrients, and pesticides, respectively, within 48 h. By day 28, all amendments were near or below pre-amendment concentrations. Water samples at 500 m showed no changes in sediment or nutrient concentrations; pesticide concentrations peaked within 48 h but at ≤11% of upstream peak concentrations and had dissipated by day 28. Managed riverine wetlands≥1 ha and with hydraulic residence times of days to weeks can efficiently trap agricultural runoff during moderate (1cm) late-spring and early-summer rainfall events, mitigating impacts to receiving rivers.

Inundation influences on bioavailability of phosphorus in managed wetland sediments in agricultural landscapes.

Agricultural runoff carries high nutrient loads to receiving waters, contributing to eutrophication. Managed wetlands can be used in integrated management efforts to intercept nutrients before they enter downstream aquatic systems, but detailed information regarding sorption and desorption of P by wetland sediments during typical inundation cycles is lacking. This study seeks to quantify and elucidate how inundation of wetland sediments affects bioavailability of P and contributions of P to downstream systems. A managed wetland cell in Tunica County, Mississippi was subjected to a simulated agricultural runoff event and was monitored for bioavailable phosphorus (water-extractable P [P], Fe-P, and Al-P) of wetland sediments and water level during the runoff event and for 130 d afterward. Inundation varied longitudinally within the wetland, with data supporting significant temporal relationships between inundation and P desorption. Concentrations of P were significantly higher at the site that exhibited variable hydroperiods (100 m) as compared with sites under consistent inundation. This suggests that sites that are inundated for longer periods of time desorb less P immediately to the environment than sites that have periodic or ephemeral inundation. Concentrations of iron oxalate and NaOH-P were significantly higher at the least inundated site as compared with all other sites (F = 5.43; = 0.001) irrespective of time. These results support the hypothesis that increased hydraulic residence time decreases the bioavailability of P in wetland sediments receiving agricultural runoff. This finding suggests that the restoration of wetlands in the mid-southern United States may be hydrologically managed to improve P retention.

Current- and past-use pesticide prevalence in drainage ditches in the Lower Mississippi Alluvial Valley.

BACKGROUND: Pesticide application is common in agriculture and often results in applied pesticides entering adjacent aquatic systems. This study seasonally analyzed a suite of 17 current- and past-use pesticides in both drainage waters and sediments to evaluate the prevalence of pesticides in drainage ditches across the Lower Mississippi Alluvial Valley (LMAV). RESULTS: There were significantly higher concentrations (P<0.05) of current-use than past-use pesticides; however, there were consistently high numbers of detections of past-use pesticides in sediments. Sediment pesticide concentrations were an order of magnitude higher (150-1035 µg kg(-1)) than water samples (6-20.9 µg L(-1)). Overall, 87% of all samples analyzed for current- and past-use pesticides were non-detects. p,p'-DDT was detected in 47.5% of all drainage waters and sediments sampled. There were significant correlations (0.372≥r2≤0.935) between detected current-use water and sediment concentrations, but no significant correlations between past-use water and sediment concentrations. CONCLUSION: Overall, there was a high percentage (87%) of sediment and water samples that did not contain detectable concentrations above the lower limit of analytical detection for each respective pesticide. This lack of pesticide prevalence highlights the improved conditions in aquatic systems adjacent to agriculture and a potential decrease in toxicity associated with pesticides in agricultural landscapes in the LMAV.

Five-year quality of life results of the randomized clinical phase III (RADPLAT) trial, comparing concomitant intra-arterial versus intravenous chemoradiotherapy in locally advanced head and neck cancer.

BACKGROUND: The purpose of this investigation was to present 5-years of quality-of-life (QOL) results of a multicenter randomized phase III trial, assessing intra-arterial (IA) versus standard intravenous (IV) chemoradiation for inoperable stage IV head and neck cancer. METHODS: Evaluation of 71 patients through European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core Module (EORTC QLQ-C30) and Head and Neck Module (QLQ-H&N35), and trial-specific questionnaires. Treatment consisted of standard radiotherapy with 4 weekly IA or 3 weekly IV cisplatin infusions. RESULTS: No significant differences in treatment-related QOL problems between 1 and 5 years posttreatment were observed, except for "dry mouth" (gradually improving; p = .004). Survivors have lower fatigue levels (p = .04), better voice (p = 0.3), and swallowing (p = .03) than patients who could not complete all subsequent follow-up questionnaires. CONCLUSIONS: Most treatment-related QOL issues deteriorate during treatment, improve in the first year, and then remain stable, except xerostomia, improving up to the 5-year assessment point. Survivors show more positive scores for fatigue, voice, and swallowing. QOL issues at 1 year, thus, for most already represent those after 5-year follow-up.

Managing artificially drained low-gradient agricultural headwaters for enhanced ecosystem functions.

Large tracts of lowlands have been drained to expand extensive agriculture into areas that were historically categorized as wasteland. This expansion in agriculture necessarily coincided with changes in ecosystem structure, biodiversity, and nutrient cycling. These changes have impacted not only the landscapes in which they occurred, but also larger water bodies receiving runoff from drained land. New approaches must append current efforts toward land conservation and restoration, as the continuing impacts to receiving waters is an issue of major environmental concern. One of these approaches is agricultural drainage management. This article reviews how this approach differs from traditional conservation efforts, the specific practices of drainage management and the current state of knowledge on the ecology of drainage ditches. A bottom-up approach is utilized, examining the effects of stochastic hydrology and anthropogenic disturbance on primary production and diversity of primary producers, with special regard given to how management can affect establishment of macrophytes and how macrophytes in agricultural landscapes alter their environment in ways that can serve to mitigate non-point source pollution and promote biodiversity in receiving waters.

Chemical residence time and hydrological conditions influence treatment of fipronil in vegetated aquatic mesocosms.

Fipronil, a phenyl-pyrazole insecticide, is often used in rice (Oryza sativa L.) production agriculture, with elevated runoff concentrations and loads having potential toxicological effects on downstream aquatic environments. This study evaluated two species of aquatic plants-broadleaf cattail (Typha latifolia L.) and powdery alligator-flag (Thalia dealbata Fraser ex Roscoe)-placed in series against a nonvegetated mesocosm in reducing concentrations and loads of fipronil, and associated metabolites. Vegetation type and hydrological condition (inundated vs. dry) were treatment effects used for comparison. The vegetated mesocosms significantly reduced higher loads and concentrations of fipronil, fipronil sulfone, and sulfide in both inundated and dry hydrological conditions over nonvegetated nesocosms. Under inundation conditions, vegetated mesocosms reduced >50% of influent fipronil concentrations and betweeen 60 and 70% of fipronil loads, which was significantly higher than the dry conditions (10-32% concentration and load). These results show that agricultural management strategies usingephemeral aquatic zones, such as drainage ditches, can be optimized to couple chemical applications with vegetation presence and hydrology to facilitate the reduction in chemical waste loads entering downstream aquatic ecosystems. Such reduction is critical for use with fipronil, where negative impacts have been demonstrated with several nontarget species.

Role of vegetation in a constructed wetland on nutrient-pesticide mixture toxicity to Hyalella azteca.

The toxicity of a nutrient-pesticide mixture in nonvegetated and vegetated sections of a constructed wetland (882 m² each) was assessed using Hyalella azteca 48-h aqueous whole-effluent toxicity bioassays. Both sections were amended with a mixture of sodium nitrate, triple superphosphate, diazinon, and permethrin simulating storm-event agricultural runoff. Aqueous samples were collected at inflow, middle, and outflow points within each section 5 h, 24 h, 72 h, 7 days, 14 days, and 21 days postamendment. Nutrients and pesticides were detected throughout both wetland sections with concentrations longitudinally decreasing more in vegetated than nonvegetated section within 24 h. Survival effluent dilution point estimates-NOECs, LOECs, and LC50s-indicated greatest differences in toxicity between nonvegetated and vegetated sections at 5 h. Associations of nutrient and pesticide concentrations with NOECs indicated that earlier toxicity (5-72 h) was from permethrin and diazinon, whereas later toxicity (7-21 days) was primarily from diazinon. Nutrient-pesticide mixture concentration-response assessment using toxic unit models indicated that H. azteca toxicity was due primarily to the pesticides diazinon and permethrin. Results show that the effects of vegetation versus no vegetation on nutrient-pesticide mixture toxicity are not evident after 5 h and a 21-day retention time is necessary to improve H. azteca survival to ≥90% in constructed wetlands of this size.

Intra-arterial versus intravenous chemoradiation for advanced head and neck cancer: Results of a randomized phase 3 trial.

BACKGROUND: Chemoradiation is the preferred treatment for advanced stage IV head and neck cancer. Higher doses of chemotherapy yielded promising results in vitro and vivo, confirmed by intra-arterial (IA) cisplatin-based chemoradiation in phase 2 studies. METHODS: Two hundred and thirty-nine patients with (functionally) unresectable head and neck cancer were included, from 2000 to 2004, in a multicenter, randomized phase 3 trial, comparing IA and intravenous chemoradiation. Intravenous chemoradiation comprised 3x100 mg/m(2) cisplatin infusion on Days 1, 22, 43 combined with 70 Gy in 35 daily fractions. The IA chemoradiation treatment arm comprised 4x150 mg/m(2) cisplatin administered in the tumor-feeding artery on Days 1, 8, 15, 22, immediately followed by systemic rescue with sodium thiosulfate with the same radiotherapeutic regimen. RESULTS: Two patients were excluded from analysis because of nontreatment-related death immediately after randomization (n = 1) and esophageal carcinoma (n = 1). The median follow-up was 33 months 1-104 months. Ninety percent of the patients required tube feeding during treatment. Renal toxicity >grade 2 was 9% in the intravenous compared with 1% in the IA treatment arm (P

Diazinon reduction and partitioning between water, sediment and vegetation in stormwater runoff mitigation through rice fields.

BACKGROUND: Contamination of surface waters by pesticides is a concern in the United States and around the world. Innovative mitigation strategies are needed to remediate this potential environmental contaminant. One potential solution is to divert pesticide-laden drainage or surface water through agricultural rice fields. With a hydroperiod, hydrosoil and hydrophyte (rice), these systems serve essentially as a type of constructed wetland. In both summer and fall experiments, diazinon-amended water was diverted through two rice ponds at the University of Mississippi Field Station. Likewise, a non-vegetated control pond was amended with diazinon-laden water. Water, sediment and plant samples were taken spatially and temporally to determine the distribution of diazinon within systems. RESULTS: Outflow diazinon concentrations decreased significantly (P < 0.05) from inflow in both vegetated ponds for both preharvest and post-harvest experiments. Although sorption to rice plants was minimal in the overall mass distribution of diazinon (1-3%), temporal data indicated that diazinon concentrations reached the outflow sediment of the non-vegetated control twice as fast as in either vegetated (rice) system. In both vegetated systems, sediment diazinon concentrations decreased (77 and 100%) from inflow to outflow, while a decrease of <2% was noted in the non-vegetated control. CONCLUSIONS: Diversion of pesticide-contaminated water through rice fields demonstrated potential as a low-cost, environmentally efficient mitigation practice. Studies on these systems are continuing to evaluate the optimal chemical retention time for rice field mitigation, as well as diazinon transfer to rice grain seeds that may be used as a food source.

Survival, growth, and body residues of hyalella azteca (Saussure) exposed to fipronil contaminated sediments from non-vegetated and vegetated microcosms.

We assessed chronic effects of fipronil and metabolite contaminated sediments from non-vegetated and Thallia dealbata vegetated wetland microcosms on Hyalella azteca during wet and dry exposures. Mean sediment concentrations (ng g(-1)) ranged from 0.72-1.26, 0.01-0.69, 0.07-0.23, and 0.49-7.87 for fipronil, fipronil-sulfide, fipronil-sulfone, and fipronil-desulfinyl, respectively. No significant differences in animal survival or growth were observed between non-vegetated and vegetated microcosms during wet or dry exposures. Mean animal body residue concentrations (ng g(-1)) ranged from 28.4-77.6, 0-30.7, and 8.3-43.8 for fipronil, fipronil-sulfide, and fipronil-sulfone. Fipronil-desulfinyl was not detected in any animal samples.

Efficiency of experimental rice (Oryza sativa L.) fields in mitigating diazinon runoff toxicity to Hyalella azteca.

This study assessed the viability of using planted, mature rice fields in mitigating diazinon (an organophosphate insecticide) runoff toxicity using aqueous 48 h Hyalella azteca whole effluent toxicity bioassays. Rice fields decreased diazinon concentrations 80.1%-99.9% compared with 10.8% in the unvegetated field control. H. azteca survival responses coincided with observed diazinon concentrations. Estimated LC50 effects dilutions (%) ranged from 1.15 to 1.47 for inflow samples and 1.66 (unvegetated), 6.44 (rice field A), and >100 (rice field B) outflow samples. Decreases in inflow versus outflow aqueous toxicity were 77.1%-100% in rice fields compared with 18.7% in the unvegetated field.

First-year quality of life assessment of an intra-arterial (RADPLAT) versus intravenous chemoradiation phase III trial.

BACKGROUND: We report the results of a multicenter randomized phase III study, assessing quality of life (QOL) in intra-arterial (IA) versus standard intravenous (IV) chemoradiation in advanced head and neck cancer. METHODS: Two hundred seven patients with inoperable stage IV disease-152 men and 55 women; mean age, 55 years-were included in this study. The patients were treated with standard radiotherapy with 4 weekly IA or 3 weekly IV cisplatin infusions. The QOL assessments carried out were EORTC-C30, H&N35, and trial-specific questionnaires. RESULTS: Overall QOL deteriorated in all patients during treatment, is gradually improving over 1 year. IA patients showed significantly less nausea and vomiting at week 7 (p <.001). IV patients were significantly more fatigued (p <.006). At 1 year, no significant difference in tube feeding was found. Voice quality slightly exceeded the pretreatment values at 1 year. Forty-two of 62 employed patients returned to work. CONCLUSION: During treatment, significantly fewer problems with nausea and vomiting occurred in IA than in IV patients. Both groups showed improved voicing and oral intake during follow-up, often exceeding pretreatment values at 1 year.

Utilization of common ditch vegetation in the reduction of fipronil and its sulfone metabolite.

BACKGROUND: Fipronil, a phenylpyrazole insecticide, and its oxidative sulfone metabolite are two potential pollutants from treated rice and cotton production. A consequence of these pollutants occurring in surface runoff is degradation of downstream aquatic ecosystems. Utilization of primary intercept drainage ditches as management practices to reduce fipronil concentrations and loads has not been examined. This study used ditch mesocosms planted with monospecific stands of common emergent wetland vegetation to determine if certain plant species were more proficient in fipronil mitigation. RESULTS: Three replicates of four plant species were compared against a non-vegetated control to determine differences in water column outflow concentrations (microg L(-1)) and loads (microg). There were no significant differences between vegetated and control treatments in outflow concentrations (F = 0.35, P = 0.836) and loads (F = 0.35, P = 0.836). The range of fipronil reduction was 28-45% for both concentration and load. Unlike fipronil, fipronil sulfone concentrations and load increased by 96-328%. CONCLUSION: The increase in fipronil sulfone was hypothesized as a direct consequence of oxidation of fipronil within each mesocosm. The type of ditch vegetation had no effect on fipronil reduction. Future research needs to examine initial concentrations and hydraulic retention times to examine potential changes in reduction capacities.

Introduction of lymphangiography and percutaneous embolization of the thoracic duct in a stepwise approach to the management of chylous fistulas.

BACKGROUND: Chylous fistula occurring after head and neck or thoracic surgery is an uncommon but well-described complication, with a reported incidence of 1% to 2.5%. Conservative management can be successful and consists of dietary measures combined with suction drainage. This article reports on percutaneous embolization of the thoracic duct through catheterization of the retroperitoneal lymph vessels. METHODS: Two patients, in whom conservative management for cervical chylous fistula failed, underwent lymphangiography with opacification of the thoracic duct, followed by radioguided catheterization and embolization. RESULTS: Embolization was successful in both patients. In 1 patient the procedure had to be repeated once to stop the chylous drainage. CONCLUSIONS: Radioguided percutaneous catheterization and embolization of the retroperitoneal lymph vessels offers an excellent treatment option for patients with persistent chylous fistulas after failure of conservative management. We revised our stepwise management protocol (de Gier, Head Neck 1996; 18:347-351) and now consider this procedure as the secondary intervention step.

Ultrasonography and fine-needle aspiration cytology can spare breast cancer patients unnecessary sentinel lymph node biopsy.

BACKGROUND: Some 30% to 40% of the breast cancer patients scheduled for sentinel node biopsy have axillary metastasis. Pilot studies suggest that ultrasonography is useful in the preoperative detection of such nodes. The aims of this study were to evaluate the sensitivity of preoperative ultrasonography and fine-needle aspiration cytology for detecting axillary metastases and to assess how often sentinel node biopsy could be avoided. METHODS: Between October 1999 and December 2003, 726 patients with clinically negative lymph nodes were eligible for sentinel node biopsy. A total of 732 axillae were examined. Preoperative ultrasonography with subsequent fine-needle aspiration cytology in case of suspicious lymph nodes was performed in all patients. The sentinel node procedure was omitted in patients with tumor-positive axillary lymph nodes in lieu of axillary lymph node dissection. RESULTS: Ultrasound and fine-needle aspiration cytology established axillary metastases in 58 (8%) of the 726 patients. These 58 were 21% of the total of 271 patients who were proven to have axillary metastasis in the end. Of the patients with ultrasonographically suspicious lymph nodes and negative cytology, 31% had tumor-positive sentinel nodes. Patients with preoperatively established metastases by ultrasonography and fine-needle aspiration cytology had more tumor-positive lymph nodes (P < .001) than patients with metastases established later on. CONCLUSIONS: The sensitivity of ultrasonography and fine-needle aspiration cytology is 21%, and unnecessary sentinel node biopsy is avoided in 8% of the patients. This approach improves the selection of patients eligible for sentinel node biopsy.