Global Forum of Cancer Surgeons: Cancer Surgery During the COVID-19 Pandemic: Impact and Lessons Learned

Annals of Surgical Oncology - The purpose of this article is to summarize the opinions of the surgical oncology leaders from the Global Forum of Cancer Surgeons (GFCS) about the global impact of...     

FDG-PET Detected Thyroid Incidentalomas: Need for Further Investigation?

Background Incidental thyroid abnormalities are increasingly detected in patients undergoing PET scans. The aim of this study was to review our experience with the management of PET detected thyroid incidentalomas in a large single institution series. Methods All PET scans performed from May 2003 to July 2005 were reviewed and patients with incidental thyroid abnormalities were identified. From this group, patients that underwent further investigation were analyzed. Data relating to PET scan findings, FNA diagnoses, operative details, and histopathology was reviewed. Results In 8,800 patients, 16,300 PET scans were performed of whom 263 patients (2.9% of patients and 1.6% of PET scans) had findings positive for thyroid abnormality. Thyroid malignancy was noted in 42% (24 patients) of the 57 patients that underwent FNA. In the group of 27 patients that were subjected to operative intervention, 74% (20 patients) were noted to have a malignant diagnosis. The final histopathology revealed primary thyroid carcinoma in all these 20 patients (19 patients with papillary carcinoma and one patient with primary thyroid lymphoma). The factors that correlated with an increased risk of malignancy were the presence of physical finding (p = 0.01) and focal (p < 0.01) or unilateral uptake (p < 0.01) on PET scan. The average SUV was not useful in differentiating benign (9.2) from malignant lesions (8.2, p = 0.7). Conclusions PET detected incidental thyroid abnormalities are rare. In patients with positive PET scan findings and suspicious features, the incidence of primary thyroid malignancy is very high. These patients warrant further investigation followed by possible operative intervention.     

Left Ventricular Lateral Annulus and Left Atrial Free‐Wall Velocity Time Integral Indicate Thromboembolism in Patients with Rheumatic Atrial Fibrillation

Background: Low wall motion and stasis increase the likelihood of clot formation. We hypothesized that tissue Doppler indices of left atrial (LA) motion are reduced in the presence of LA thrombi and may be predictive for clot formation in patients with atrial fibrillation (AF). Methods: We did an observational study for 3 years in 118 patients with rheumatic mitral valve disease in chronic AF who had not received anticoagulation, with (Group 1, n = 36) and without (Group 2, n = 82) thromboembolism. Pulsed tissue Doppler systolic velocities and velocity time integrals (VTIs) were measured in all four chambers. A mean LA VTI was calculated. LA strain during ventricular systole was calculated using VTI and distance between two LA locations. Results: Logistic regression analysis showed that, after adjusting for age, gender, diabetes, hypertension, LA size, and left ventricular (LV) ejection fraction, mean LA VTI [Odds ratio (OR) 0.69, 95%CI (0.56–0.86, P = 0.03)] and lateral mitral annulus VTI [OR 0.15 (0.04–0.56, P = 0.03)] were associated with clot formation. The addition of these two parameters to the conventional risk factors increased the ability to predict thromboembolism (Nagelkerke R²= 0.32–0.50, P = 0.01; area under the curve 0.83 by receiver operating characteristic analysis, P = 0.01). LA strain also had potential to indicate clot formation (0.9 ± 13.8 vs. ?8.2 ± 15.1%, group 1 vs. 2, respectively, P = 0.01). Conclusion: Patients with chronic AF and thromboembolism have reduced LA and LV motion independently of LA size and LV ejection fraction. Tissue Doppler parameters may have potential to predict clot formation in these patients. (Echocardiography 2010;27:1038‐1048)     

Histological Aggressiveness of Fluorodeoxyglucose Positron-Emission Tomogram (FDG-PET)-Detected Incidental Thyroid Carcinomas

Background We previously reported a high incidence of primary thyroid cancer in fluorodeoxyglucose positron-emission tomogram (FDG-PET)-detected incidental thyroid abnormalities. The aim of our study was to determine if these FDG-PET-detected thyroid malignancies represent a more-aggressive variant of primary thyroid carcinoma. Materials and methods All patients that underwent operative intervention for FDG-PET-detected incidental thyroid abnormalities were identified (June 2003 to April 2006). Patients with a diagnosis of primary thyroid carcinoma on final histopathology were included in the study. The patient demographics and histopathological findings were analyzed to identify adverse prognostic features. Results In 11,500 patients, 17,250 FDG-PET scans were performed; 377 of these patients (3.2% of patients and 2.1% of FDG-PET scans) had findings positive for thyroid abnormality. Of the 32 patients that underwent operative intervention, 22 patients with a final diagnosis of primary thyroid malignancy were included in the study. A greater number of patients [12 patients, (54%)] were noted to harbor poor prognostic variants of primary thyroid carcinoma on final histopathology [tall-cell variant: 11 patients (50%) and poorly differentiated thyroid carcinoma: 1 patient (4%)]. Extra-thyroidal extension (ETE) was noted in the majority of patients [14 patients (63%)]. In patients with tall cell variant on final histopathology, the rate of ETE was even higher [10 patients (90%)]. Conclusion Thyroid malignancies incidentally detected on FDG-PET scan harbor a high rate of unfavorable prognostic features and may represent a more-aggressive variant of primary thyroid carcinoma. These patients need to be subjected to further investigation with a view to possible operative intervention.     

Functional role of CLC-2 chloride inward rectifier channels in cardiac sinoatrial nodal pacemaker cells

A novel Cl⁻ inward rectifier channel (Cl,ir) encoded by ClC-2, a member of the ClC voltage-gated Cl⁻ channel gene superfamily, has been recently discovered in cardiac myocytes of several species. However, the physiological role of Cl,ir channels in the heart remains unknown. In this study we tested the hypothesis that Cl,ir channels may play an important role in cardiac pacemaker activity. In isolated guinea-pig sinoatrial node (SAN) cells, Cl,ir current was activated by hyperpolarization and hypotonic cell swelling. RT-PCR and immunohistological analyses confirmed the molecular expression of ClC-2 in guinea-pig SAN cells. Hypotonic stress increased the diastolic depolarization slope and decreased the maximum diastolic potential, action potential amplitude, APD₅₀, APD₉₀, and the cycle-length of the SAN cells. These effects were largely reversed by intracellular dialysis of anti-ClC-2 antibody, which significantly inhibited Cl,ir current but not other pacemaker currents, including the hyperpolarization-activated non-selective cationic “funny” current (I_f), the L-type Ca²⁺ currents (I_Ca,L), the slowly-activating delayed rectifier I_Ks and the volume-regulated outwardly-rectifying Cl⁻ current (I_Cl,vol). Telemetry electrocardiograph studies in conscious ClC-2 knockout (Clcn2^−/−) mice revealed a decreased chronotropic response to acute exercise stress when compared to their age-matched Clcn2^+/+ and Clcn2^+/− littermates. Targeted inactivation of ClC-2 does not alter intrinsic heart rate but prevented the positive chronotropic effect of acute exercise stress through a sympathetic regulation of ClC-2 channels. These results provide compelling evidence that ClC-2-encoded endogenous Cl,ir channels may play an important role in the regulation of cardiac pacemaker activity, which may become more prominent under stressed or pathological conditions.     

Polypoid esophageal adenocarcinoma--a clinicopathological variant of esophageal cancer?

PURPOSE: Neoplastic polyps are common in the colon, but not elsewhere in the gastrointestinal tract. They are rare at the gastroesophageal junction, especially associated with Barrett's dysplasia or adenocarcinoma. We identify a subset of early esophageal adenocarcinomas that present as symptomatic polyps with gastrointestinal bleeding, reflux, and even dysphagia. Because little is known about polypoid esophageal adenocarcinomas, we examine the clinical presentation, pathological features, and postoperative outcomes of these lesions. METHODS: We defined esophageal polyps as macroscopic, well-demarcated projections above the mucosa that project the greater percentage of their mass into the lumen without central ulceration. From a consecutive series of 400 patients who underwent esophagectomies for adenocarcinoma (1988 to 2000), 14 (4%) had polyps on presentation. Clinical records, pathology reports, photographs, and original slides of these resected specimens were reviewed. RESULTS: All patients with polyps had early staged esophageal adenocarcinomas. Lymph node involvement was found in only 4 patients, and no patients with distant metastases were found. All but 1 patient (13 of 14; 93%) were symptomatic at diagnosis. Most presented either with gastrointestinal bleeding or gastroesophageal reflux (11 of 14; 79%). Only 2 patients complained of mild dysphagia, and mean weight loss of the series was minimal at 1.3 +/- 4.0 kg (range, 0 to 15 kg). Barrett's was present in 10 patients (71%), and in 80% of these cases, high-grade dysplasia was found. The polyps were small 3.4 +/- 1.1 cm, and most contained poorly differentiated adenocarcinomas. No postoperative mortalities occurred, and follow-up was complete at 100%. Actuarial 2-year survival was 88%, with a mean survival of 61.3 months. Recurrent disease was identified in 4 patients. CONCLUSIONS: Polypoid adenocarcinomas of the distal esophagus are a subset of esophageal cancer that produce clear symptoms at an early tumor stage, which allows prompt detection and favorable prognosis. Their pathological features and demographics suggest an origin via the Barrett's esophagus-dysplasia-carcinoma sequence.