Processing Sentinel Nodes: When and How Many?

Background: Processing multiple sentinel nodes (SN) is expensive and time consuming. The aim of this study was to analyze a series of SNs from node positive breast cancer patients in order to determine their diagnostic value and delineate a working algorithm.Materials and methods: A prospective database of 105 node positive breast cancer patients undergoing a SN biopsy was created. The SN biopsies were performed with Technetium sulfur colloid, blue dye (Isosulfan Blue or Patent Blue) or both. SN were defined as any blue, suspicious node or radioactive nodes up to 10% of the hottest node. Location of the nodes, criteria of SN definition (hot/blue/suspicious), ten second radioactive counts and pathologic status were recorded. A statistical analysis of the diagnostic value of those nodes was performed.Results: Three hundred and seventy five SNs were recorded in the database. The number of nodes per patient ranged from 1 to 15 with a median value of 3. Radioactivity was found in a total of 322 (86%) sentinel nodes and blue dye in a total of 105 (28%) nodes, with 92 (25%) nodes being both hot and blue. Fourty (11%) sentinel nodes were removed for suspicious appearance. One hundred fifty nine (42%) of the 375 sentinel nodes tested positive for disease. Among the 159 positive nodes, 139 (87%) were radioactive, 52 (33%) were blue, and 46 (29%) were both hot and blue. An analysis of the 322 radioactive nodes reveals that the most radioactive node was positive in 74/95 analyzable patients (77.9%). Consideration of the two most intense nodes was sufficient to diagnose nodal disease in an additional 15 patients, representing a significant increase in sensitivity to 93.7%, p<0.001. Examination of all other radioactive nodes diagnosed one more patient only but the increase in sensitivity, to 94.7%, was not significant (p=1.00).Sensitivity and Nodes Required for Diagnostic Tests Based on Hot Sentinel Nodes   Nodes testedDiagnostic testSensitivity1 (95% CI2)Sensitivity1 (95% CI2)p-value3Median (range) per patientTotalAverage4Hottest node74/9577.9% (68.2-85.8%)-1951.0Two hottest nodes89/9593.7% (86.8-97.7%)<0.0012(1-2)701.9All hot nodes90/9594.7% (88.1-98.3%)1.003 (1 to 15)3033.21. Conditional sensitivity in SN-positive women. 2. 95% exact confidence interval. 3. Exact p-value, McNemar's test for a difference relative to the preceding row. 4. Average nodes required per patient.In patients with both radioactive and blue SNs, non radioactive blue nodes did not add significant diagnostic value.Non-radioactive blue nodes did not add significant diagnostic value.    Nodes testedDiagnostic testSensitivity1 (95% CI2)Sensitivity1 (95% CI2)P-value3Median (range) per patientTotalAverage4Hot nodes596/10591.4% (84.4 to 96%)-33223.1Hot or blue nodes98/10593.3% (86.8 to 97.3%)0.5003 (0 to 15)3353.21. Conditional sensitivity in SN-positive women. 2. 95% exact confidence interval. 3. Exact p-value, McNemar's test for a difference relative to the preceding row. 4. Average nodes required per patient. 5. Nine false negatives are comprised of 4 patients with no hot nodes and 5 patients with negative hot nodes.Conclusions: Processing of the two hottest and the suspicious nodes is sufficient for the initial axillary staging. Additional SNs should be processed only in presence of nodal disease.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1007.

Epidemiologic study of 203 sibling pairs with Parkinson's disease: the GenePD study

OBJECTIVE

To examine patterns of familial aggregation and factors influencing onset age in a sample of siblings with PD.

METHODS

Sibling pairs (n = 203) with PD were collected as part of the GenePD study. Standardized family history, medical history, and risk factor data were collected and analyzed.

RESULTS

The mean age at onset was 61.4 years and did not differ according to sex, exposure to coffee, alcohol, or pesticides. Head trauma was associated with younger onset (p = 0.03) and multivitamin use with later onset (p = 0.007). Age at onset correlation between sibling pairs was significant (r = 0.56, p = 0.001) and was larger than the correlation in year of onset (r = 0.29). The mean difference in onset age between siblings was 8.7 years (range, 0 to 30 years). Female sex was associated with increased frequency of relatives with PD. The frequency of affected parents (7.0%) and siblings (5.1%) was increased when compared with frequency in spouses (2.0%).

CONCLUSIONS

The greater similarity for age at onset than for year of onset in sibling pairs with PD, together with increased risk for biological relatives over spouses of cases, supports a genetic component for PD. Risk to siblings in this series is increased over that seen in random series of PD cases; however, patients in this sample have similar ages at onset and sex distribution as seen for PD generally. These analyses suggest that factors influencing penetrance are critical to the understanding of this disease.

A randomized, controlled trial of remacemide for motor fluctuations in Parkinson's disease

BACKGROUND

Preclinical studies suggest that glutamate antagonists help ameliorate motor fluctuations in patients with PD treated with levodopa.

METHODS

In a multicenter, randomized, double-blind, placebo-controlled, parallel-group, dose-ranging study, the authors assessed the safety, tolerability, and efficacy of the glutamate receptor blocker remacemide hydrochloride in 279 patients with motor fluctuations treated with levodopa. The primary objective was to assess the short-term tolerability and safety of four dosage levels of remacemide during 7 weeks of treatment. Patients were also monitored with home diaries and the Unified PD Rating Scale (UPDRS) to collect preliminary data on treatment efficacy.

RESULTS

Remacemide was well tolerated up to a dosage of 300 mg/d on a twice daily schedule and 600 mg/d on a four times daily schedule. The most common dosage-related adverse events were dizziness and nausea, as observed in previous studies of remacemide. The percent "on" time and motor UPDRS scores showed trends toward improvement in the patients treated with 150 and 300 mg/d remacemide compared with placebo-treated patients, although these improvements were not significant.

CONCLUSION

Remacemide is a safe and tolerable adjunct to dopaminergic therapy for patients with PD and motor fluctuations. Although this study had limited power to detect therapeutic effects, the observed improvement is consistent with studies of non-human primates with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced parkinsonian signs and symptoms. Additional studies are warranted to confirm these results over an extended period of observation, and to explore the potential neuroprotective effects of remacemide in slowing the progression of PD.

Cancer among farmers: a meta-analysis

PURPOSE

We conducted a meta-analysis of 37 studies to assess whether farmers had elevated rates for several cancers, as was concluded in a previous meta-analysis of 21 studies.

METHODS

We identified studies from the reference list of the previous meta-analysis and from a MEDLINE search through December 31, 1994. The primary purpose of our analysis was to identify and, if possible, understand the sources of heterogeneity in the literature. Stratified analyses of studies and linear modeling with inverse variance weights were used to assess the impact of study characteristics on results. We calculated summary relative risks as a weighted average of the log relative risks across studies using inverse variance weights. Fixed and random effects models were used as appropriate.

RESULTS

The results for most cancers were markedly heterogeneous by study design and, for fewer cancers, by geographic location, and whether the studies focused on crop and livestock farmers. There was some indication of publication bias due to underreporting of near null or sub null findings. Lip cancer was the only cancer that was clearly elevated among farmers.

CONCLUSIONS

The results do not suggest that farmers have elevated rates of several cancers. However, the known heterogeneity of exposures by type of farming, geographic area, time period, and other factors limits the informativeness of meta-analyses of these studies for assessing potential carcinogenic exposures in agriculture.

Underrecognition of morbidity from stings of the red imported fire ant in the southeastern United States

This cross-sectional study was conducted to determine the health-seeking behaviors of a group of patients stung by red imported fire ants (RIFA) and the number of nursing referrals resulting in treatment. The following two research questions were asked: (1) Is there a delay in seeking the care of a board-certified allergist for symptoms of fire ant hypersensitivity? (2) Are nurses referring patients for treatment? The entire population of board-certified allergists in Alabama, Georgia, and South Carolina (n = 98) was sampled. A questionnaire was developed for the office nurses to use to collect information from allergy patients actually receiving fire ant injections (n = 257). Each patient reported on the reaction, when it occurred as well as age, sex, and county of residence. Descriptive statistics revealed that a delay of a month or more in seeking care of an allergist was experienced by 154 (56%) of patients who completed the questionnaire. The average delay was 1.8 years. The main source of referrals was a general practitioner or emergency room personnel. Nursing and other health professionals must recognize the problem and to institute prompt referral for treatment. In areas where RIFA colonies are spreading, they have to be fully informed and trained in effective primary and secondary techniques to prevent serious reaction to the stings of these ants.

Localization of halothane-induced antigen in situ by specific anti-halothane metabolite antibodies

Multiple or single halothane exposure of rabbits or guinea pigs induces an antibody reactive with trifluoroacetylated (TFA) proteins. The antigen that initiates this immune response was investigated in halothane-exposed rabbits and guinea pigs for its anatomical location in the liver, the chronology of its expression in situ and exposure conditions which would modulate its expression. Using an immuno-staining technique, binding by an anti-TFA antibody to the antigen was detected in liver tissue from all halothane-exposed rabbits and guinea pigs. Antigen could be detected only in the centrilobular area around the central vein where staining intensity was concentrated in an area seven to nine cells deep. In halothane-exposed rabbits, the appearance of TFA antigen was most predominant on the first and second days following a single exposure. Multiple exposures induced TFA antigen in a larger area around the central vein than did a single exposure. Though maximal expression of TFA antigen occurred following two or three exposures, subsequent exposures did not potentiate antigen expression. In halothane-exposed guinea pigs, exposure to deuterated halothane, which reduces the extent and metabolites of oxidative halothane metabolism, elicited the appearance of TFA antigen around the central veins, although to a lesser extent than during halothane exposure. Halothane-induced antigen was evident in guinea pigs as early as 6 h post-exposure and was still apparent 90 h later. Thus, halothane exposure by inhalation elicits the appearance of TFA protein conjugates which may, in turn, evoke the anti-TFA immune response.

Rat liver slices and diazepam metabolism: in vitro interactions with volatile anaesthetic drugs and albumin

The influence of the volatile anaesthetic agents enflurane, isoflurane, halothane and the halothane metabolite trifluoroacetic acid was studied on the hepatic elimination of diazepam, by incubating precision-cut slices of rat liver in a closed system. The impact of anaesthetic-induced action on enzyme activity and diazepam binding to human serum albumin (HSA) was assessed in protein free and protein containing buffers, respectively. Human serum albumin reduced the elimination of diazepam by 12 and 50% at concentrations of 1 and 10 mg ml-1, respectively. In the absence of albumin, halothane 1 mmol litre-1 reduced the elimination of diazepam by 13%, whereas enflurane at 1.5 mmol litre-1 caused a reduction of 8%. No effect was seen from isoflurane 1 mmol litre-1 and trifluoroacetic acid 4 mmol litre-1. In the presence of the highest concentration of albumin, however, an increased elimination of diazepam of 24% resulted from exposure to enflurane and trifluoroacetic acid, while no statistically significant changes were seen for isoflurane and halothane. The present work supports the view that volatile anaesthetic agents may cause pharmacokinetic drug interactions by interference with both enzyme activity and drug protein binding.