Tomer Davidov

Routine second-opinion cytopathology review of thyroid fine needle aspiration biopsies reduces diagnostic thyroidectomy

BACKGROUND Follicular thyroid carcinoma cannot be distinguished reliably from benign follicular neoplasia by fine needle aspiration (FNA) biopsy. Given an estimated 20% risk of malignancy, many patients with indeterminate FNA biopsies require thyroidectomy for diagnosis. Some centers have shown significant discordance when a second pathologist evaluates the same FNA biopsy. We sought to determine whether routine second-opinion cytopathology reduces the need for diagnostic thyroidectomy, especially in patients with indeterminate FNA biopsies. METHODS In all, 331 thyroid FNA biopsy specimens obtained from outside centers from 2004 to 2009 were reviewed at our institution. The FNA biopsy results were categorized into nondiagnostic (Bethesda I), benign (Bethesda II), indeterminate (follicular/Hurthle cell neoplasm, follicular/Hurthle cell lesion; Bethesda III & IV), and malignant (papillary or suspicious for papillary or other malignancy; Bethesda V and VI). Second-opinion cytology was compared with the initial opinion in 331 cases and with final operative pathology in the 250 patients who progressed to thyroidectomy. RESULTS The average patient age was 51 with a predominant number of female (79%) participants. The overall cytology concordance for all 331 FNA biopsies was 66% (218/331). Concordance was highest at 86% (74/86) with malignant FNA biopsies. Concordance in the 129 patients with indeterminate FNA biopsies was only 37% (48/129). Indeterminate FNA biopsies were reread as nondiagnostic in 21% (27/129) of patients and as benign in 42% (54/129) of patients. Twenty-two patients with an indeterminate FNA biopsy reread as benign progressed to operative therapy for reasons other than cytology (eg, symptomatic nodule and radiation exposure/high risk) and were found to be benign in 95% (21/22) of patients on operative pathology for a 95% negative predictive value. An additional 11 patients with an indeterminate FNA reread as benign had follow-up FNA biopsies, each of which was benign. Indeterminate FNA biopsies on initial cytology had a malignancy rate of 13% (17/129) on operative pathology compared with 29% (14/48) for indeterminate FNA biopsies from second opinion. A second opinion improved FNA biopsy accuracy from 60% to 74%. Overall, second-opinion cytology of indeterminate FNA biopsies avoided diagnostic operation in 25% (32/129). CONCLUSION Routine second opinion review of indeterminate thyroid FNA biopsies can potentially obviate the need for diagnostic thyroidectomy in 25% of patients without increases in false negatives.

Carbonic anhydrase 4 and crystallin alpha-B immunoreactivity may distinguish benign from malignant thyroid nodules in patients with indeterminate thyroid cytology

BACKGROUND Thyroid nodules are present in 19%-67% of the population and carry a 5%-10% risk of malignancy. Unfortunately, fine-needle aspiration biopsies are indeterminate in 20%-30% of patients, often necessitating thyroid surgery for diagnosis. Numerous DNA microarray studies including a recently commercialized molecular classifier have helped to better distinguish benign from malignant thyroid nodules. Unfortunately, these assays often require probes for >100 genes, are expensive, and only available at a few laboratories. We sought to validate these DNA microarray assays at the protein level and determine whether simple and widely available immunohistochemical biomarkers alone could distinguish benign from malignant thyroid nodules. METHODS A tissue microarray (TMA) composed of 26 follicular thyroid carcinomas (FTCs) and 53 follicular adenomas (FAs) from patients with indeterminate thyroid nodules was stained with 17 immunohistochemical biomarkers selected based on prior DNA microarray studies. Antibodies used included galectin 3, growth and differentiation factor 15, protein convertase 2, cluster of differentiation 44 (CD44), glutamic oxaloacetic transaminase 1 (GOT1), trefoil factor 3 (TFF3), Friedreich Ataxia gene (X123), fibroblast growth factor 13 (FGF13), carbonic anhydrase 4 (CA4), crystallin alpha-B (CRYAB), peptidylprolyl isomerase F (PPIF), asparagine synthase (ASNS), sodium channel, non-voltage gated, 1 alpha subunit (SCNN1A), frizzled homolog 1 (FZD1), tyrosine related protein 1 (TYRP1), E cadherin, type 1 (ECAD), and thyroid hormone receptor associated protein 220 (TRAP220). Of note, two of these biomarkers (GOT1 and CD44) are now used in the Afirma classifier assay. We chose to compare specifically FTC versus FA rather than include all histologic categories to create a more uniform immunohistochemical comparison. In addition, we have found that most papillary thyroid carcinoma could often be reasonably distinguished from benign disease by morphological cytology findings alone. RESULTS Increased immunoreactivity of CRYAB was associated with thyroid malignancy (c-statistic, 0.644; negative predictive value [NPV], 0.90) and loss of immunoreactivity of CA4 was also associated with malignancy (c-statistic, 0.715; NPV, 0.90) in indeterminate thyroid specimens. The combination of CA4 and CRYAB for discriminating FTC from FA resulted in a better c-statistic of 0.75, sensitivity of 0.76, specificity of 0.59, positive predictive value (PPV) of 0.32, and NPV of 0.91. When comparing widely angioinvasive FTC from FA, the resultant c-statistic improved to 0.84, sensitivity of 0.75, specificity of 0.76, PPV of 0.11, and NPV of 0.99. CONCLUSIONS Loss of CA4 and increase in CRYAB immunoreactivity distinguish FTC from FA in indeterminate thyroid nodules on a thyroid TMA with an NPV of 91%. Further studies in preoperative patient fine needle aspiration (FNAs) are needed to validate these results.

Operative bed recurrence of thyroid cancer: utility of a preoperative needle localization technique.

BACKGROUND Surgical management of recurrent disease after total thyroidectomy and/or neck dissection for thyroid carcinoma remains a challenging clinical problem. Reoperation is associated with a significant increase in morbidity. Preoperative needle localization technique for non-palpable breast tumors has recently been extrapolated to head and neck surgery. We report on the use of preoperative ultrasound-guided needle localization for non-palpable recurrent operative bed disease as an intraoperative aid in resection. METHODS Patients with thyroid carcinoma were identified from a retrospective database at a tertiary care center from 2011-2014. Inclusion criteria were history of thyroidectomy and/or neck dissection, non-palpable recurrent disease in the resection bed on surveillance, and ultrasound-guided needle localization of recurrent disease before resection. Perioperative data and outcomes were analyzed. RESULTS Seventeen patients were identified using the inclusion criteria listed above. Median patient age was 46 years (53% male, 47% female). A total of 23 masses in the previous operative bed were needle-localized successfully with no major long-term sequelae from this technique. The recurrent laryngeal nerve was involved with tumor in six patients. Two patients, in whom the tumor surrounded the nerve circumferentially, experienced recurrent laryngeal nerve injuries. No patients experienced postoperative hypocalcemia. With a routine surveillance and a median follow-up of 558 days, sixteen of the patients remain with no evidence of disease. CONCLUSIONS Preoperative ultrasound-guided needle localization of non-palpable recurrent operative bed disease after thyroidectomy and/or neck dissection is a potentially safe method to aid in resection and cure.

SERCA Inhibition Limits the Functional Effects of Cyclic GMP in Both Control and Hypertrophic Cardiac Myocytes

The negative functional effects of cyclic GMP are controlled by the sarcoplasmic reticulum calcium-ATPase (SERCA). The effects of cyclic GMP are blunted in cardiac hypertrophy. We tested the hypothesis that the interaction between cyclic GMP and SERCA would be reduced in hypertrophic cardiac myocytes. Myocytes were isolated from 7 control and 7 renal-hypertensive hypertrophic rabbits. Control and hypertrophic myocytes received 8-bromo-cGMP (8-Br-cGMP; 10–7, 10–6, 10–5 mol/l), the SERCA blocker thapsigargin (10–8 mol/l) followed by 8-Br-cGMP, or the SERCA blocker, cyclopiazonic acid (CPA; 10–7 mol/l) followed by 8-Br-cGMP. Percent shortening and maximal rate of shortening and relaxation were recorded using a video edge detector. Changes in cytosolic Ca2+ were assessed in fura 2-loaded myocytes. In controls, 8-Br-cGMP caused a significant 36% decrease in percent shortening from 5.8 ± 0.4 to 3.7 ± 0.3%. Thapsigargin and CPA did not affect basal control or hypertrophic myocyte function. When 8-Br-cGMP was given following thapsigargin or CPA, the negative effects of 8-Br-cGMP on control myocyte function were reduced. In hypertrophic myocytes, 8-Br-cGMP caused a smaller but significant 17% decrease in percent shortening from 4.7 ± 0.2 to 3.9 ± 0.1%. When 8-Br-cGMP was given following thapsigargin or CPA, no significant changes occurred in hypertrophic cell function. Intracellular Ca2+ transients responded in a similar manner to changes in cell function in control and hypertrophic myocytes. These results show that the effects of cyclic GMP were reduced in hypertrophic myocytes, but this was not related to SERCA. In presence of SERCA inhibitors, the responses to cyclic GMP were blunted in hypertrophic as well as control myocytes.

Should radiocontrast be diluted for operative cholangiography

The role of operative cholangiography for detecting common bile duct stones and for delineating biliary anatomy is well established. The first operative cholangiogram was described by Mirizzi in 1937 and popularized in the United States by Hickens. Operative cholangiography has resulted in improved detection of common bile duct stones from 83% based on clinical findings alone to over 95%.3 The introduction of portable C-arm fluoroscopy in the 1970s by Berci and Steckell has even further improved the accuracy of operative cholangiography. Controversy over the optimal concentration of iodinated radiocontrast for operative cholangiography continues to exist. In the original description of operative cholangiography, Mirizzi reported using diluted 40% lipiodol (lipoiodine). Lipiodol (iodinated poppy seed oil) has a high organic iodine content of 42% (420 mg/ml) requiring dilution. In a similar early description of cholangiography, a diluted 17.5% solution of iodopyracet (Diodrast) was used. The authors noted that this diluted contrast ‘‘did not cast too dense a shadow on the X-ray film to obscure stones.’’ Diodrast, which is rarely used today for cholangiography, has a very high 63.5% iodine content (635 mg/ml), necessitating dilution. This is in comparison to the more widely commercially available Conray (iothalamate meglumine) and Hypaque (diatrazoate sodium) both of which have an iodine content of 282 mg/ml (28.2%). Most commercially available iodinated contrast media used today (both ionic and nonionic) have organic iodine content ranging from 282 to 400 mg/ml. There is scant literature on the optimal concentration to use for operative cholangiography. One study involving over 1600 cholangiograms showed high accuracy using full strength Hypaque 60