Toxicity thresholds for juvenile freshwater mussels Echyridella menziesii and crayfish Paranephrops planifrons,after acute or chronic exposure to Microcystis sp

Survival of juvenile freshwater mussels (Echyridella menziesii (Gray, 1843) formerly known as Hyridella menziesi) and crayfish (Paranephrops planifrons, White, 1842) decreased after four days exposure to microcystin‐containing cell‐free extracts (MCFE) of Microcystis sp. at concentrations typical of severe cyanobacterial blooms. Crayfish survival was 100, 80, and 50% in microcystin concentrations of 1339, 2426, and 11146 μg L^?1 respectively, and shade‐ and shelter‐seeking behavior was negatively affected when concentrations were ≥2426 μg L^?1. Mussel survival decreased to 92% and reburial rates decreased to 16% after exposure for 96 h to MCFE containing microcystins at concentrations of 5300 μg L^?1. Crayfish survival was 100% when fed freeze‐dried Microcystis sp. incorporated into an artificial diet (6–100 μg microcystin kg^?1 ww) at dietary doses from 0.03 to 0.55 μg g^?1 body weight d^?1 for 27 days. Specific growth rate was significantly lower in crayfish fed ≥0.15 μg g^?1 body weight day^?1 compared with controls, but not compared with a diet incorporating nontoxic cyanobacteria. Microcystins accumulated preferentially in crayfish hepatopancreas and mussel digesta as MCFE or dietary concentrations increased. These laboratory data indicate that, assuming dissolved oxygen concentrations remain adequate, and no simultaneous exposure to live Microcystis sp. cells, cell‐free microcystins will only be a significant stressor to juvenile crayfish and mussels in severe Microcystis sp. blooms. In contrast, crayfish were negatively affected by relatively low concentrations of microcystins in artificial diets compared with those measured locally in benthic cyanobacterial mats. © 2012 Wiley Periodicals, Inc. Environ Toxicol 29: 487–502, 2014.     

Reoperative Experience with Papillary Thyroid Cancer

Background

Intense postoperative monitoring has resulted in increasing detection of patients with recurrent papillary thyroid cancer (PTC). Our goals included quantifying successful reoperation, and analyzing surgical complications and reasons for relapse.

Methods

From 1999 to 2008, a total of 410 patients underwent reoperation for PTC relapse. We analyzed post-reoperative disease outcomes, reasons for relapse, and complications.

Results

Bilateral reoperative thyroidectomy was performed in 13 (3 %) patients; lobectomy, 34 (8 %); central neck (VI) soft tissue local recurrence excision, 47 (11.5 %); bilateral VI node dissection, 107 (26 %); unilateral VI dissection, 112 (27 %); levels II–V dissection, 93 (23 %); levels III–V, 86 (21 %); lateral single- or two-compartment dissection, 51 (12 %); and node picking, 20 (5 %) of level VI and 53 (13 %) lateral neck. Complications occurred in 6 %; including hypoparathyroidism, 3 %; unintentional recurrent laryngeal nerve (RLN) paralysis, 3 %; phrenic nerve injury, 0.5 %; spinal accessory nerve injury, 0.5 %; and chyle leak in 1.6 %. Of 380 (93 %) patients with follow-up (mean 5.2 years); 274 (72 %) patients are alive with no structural evidence of disease, 38 % developed disease relapse (mean 2.1 years), 42 (11 %) died from PTC, and 55 (14 %) are alive with disease. The reason for relapse was a false negative pre-reoperative ultrasound (US) in 18 (5 %), nodal recurrence in the operative field in 37 (10 %), a combination of these two reasons in 10 (3 %), and disease virulence (local or systemic recurrence) in 81 (21 %).

Conclusions

Although 72 % of patients were rendered structurally disease free after reoperation, nearly 40 % suffered additional relapse. Improved surgical technique or preoperative localization might positively affect 15–20 %; at least 20 % reflect the biologic aggressiveness of the disease.     

Primary Gleason Grade 4 at the Positive Margin Is Associated with Metastasis and Death Among Patients with Gleason 7 Prostate Cancer Undergoing Radical Prostatectomy

Background

The presence of a positive surgical margin (PSM) at radical prostatectomy (RP) has been linked to an increased risk of biochemical recurrence and receipt of secondary therapy; however, its association with other oncologic end points remains controversial.

Objective

To evaluate the association of primary Gleason grade (GG) at the site of PSM with subsequent clinical progression and mortality among patients with Gleason score (GS) 7 prostate cancer (PCa).

Design, setting, and participants

We identified 1036 patients who underwent RP between 1996 and 2002. A single uropathologist re-reviewed all specimens noted to have a PSM to record GG at the margin.

Outcome measurements and statistical analysis

Survival was estimated using the Kaplan-Meier method. Cox models were used to analyze the association of margin primary GG with outcome.

Results and limitations

Overall, 338 men (33%) had a PSM; of those, 242 had PSM GG3 and 96 had PSM GG4. Median postoperative follow-up was 13 yr. Compared with men with PSM GG3 or a negative SM, we noted that men with PSM GG4 had significantly worse 15-yr systemic progression-free survival (74% vs 90% vs 93%, respectively; p < 0.001) and cancer-specific survival (86% vs 96% vs 97%, respectively; p = 0.002). On multivariable analysis, the presence of PSM GG4 was associated with increased risks of systemic progression (hazard ratio [HR]: 2.77; p = 0.003) and death from PCa (HR: 3.93; p = 0.02) among men with a PSM. Limitations include the relatively small rate of disease recurrence.

Conclusions

PSM primary GG4 was independently associated with adverse oncologic outcomes among men with GS7 PCa. Pending external validation, GG at the PSM may be considered for inclusion in pathologic reports and risk stratification following RP.

Patient summary

Among patients with Gleason grade 7 prostate cancer and a positive surgical margin at the time of prostatectomy, we found that higher Gleason grade at the margin was associated with worse oncologic outcomes.     

Current Perspectives in the Use of Molecular Imaging To Target Surgical Treatments for Genitourinary Cancers

Context

Molecular imaging (MI) entails the visualisation, characterisation, and measurement of biologic processes at the molecular and cellular levels in humans and other living systems. Translating this technology to interventions in real-time enables interventional MI/image-guided surgery, for example, by providing better detection of tumours and their dimensions.

Objective

To summarise and critically analyse the available evidence on image-guided surgery for genitourinary (GU) oncologic diseases.

Evidence acquisition

A comprehensive literature review was performed using PubMed and the Thomson Reuters Web of Science. In the free-text protocol, the following terms were applied: molecular imaging, genitourinary oncologic surgery, surgical navigation, image-guided surgery, and augmented reality. Review articles, editorials, commentaries, and letters to the editor were included if deemed to contain relevant information. We selected 79 articles according to the search strategy based on the Preferred Reporting Items for Systematic Reviews and Meta-analysis criteria and the IDEAL method.

Evidence synthesis

MI techniques included optical imaging and fluorescent techniques, the augmented reality (AR) navigation system, magnetic resonance imaging spectroscopy, positron emission tomography, and single-photon emission computed tomography. Experimental studies on the AR navigation system were restricted to the detection and therapy of adrenal and renal malignancies and in the relatively infrequent cases of prostate cancer, whereas fluorescence techniques and optical imaging presented a wide application of intraoperative GU oncologic surgery. In most cases, image-guided surgery was shown to improve the surgical resectability of tumours.

Conclusions

Based on the evidence to date, image-guided surgery has promise in the near future for multiple GU malignancies. Further optimisation of targeted imaging agents, along with the integration of imaging modalities, is necessary to further enhance intraoperative GU oncologic surgery.