Quantifying the differences in surgical management of patients with definitive and indeterminate thyroid nodule cytology

INTRODUCTION

Thyroid nodules are increasingly common. Despite being an essential pre-operative diagnostic tool, up to 30% of fine needle aspirate cytology (FNAC) yields a non-definitive diagnosis. This study aimed to quantify differences in surgical management of patients with definitive and indeterminate thyroid nodule cytology, and determine if clinical factors can improve cytological diagnosis.

MATERIALS AND METHODS

Patients who underwent thyroidectomy for nodules from 2001 to 2015 were recruited. Those with benign and malignant preoperative cytology were included in the "definitive diagnosis" (DC) group; patients with all other preoperative cytology results were included in the "indeterminate diagnosis" (IC) group. We compared demographics and procedures between these groups. Clinical factors and demographics were also compared between patients with benign and malignant histology in the IC group.

RESULTS

A total of 3821 cases were included. A significantly larger proportion of the IC patients had a hemithyroidectomy (IC 69% vs. DC 39%, p < 0.001) initially, and also had a significantly higher rate of two-stage surgery compared to the DC group (IC 17% vs. DC 11%, p < 0.001). Patients in the DC group were twice as likely to undergo concurrent central lymph node dissection for papillary and medullary cancers than the IC group (p < 0.001). Overall, up to 60% of IC patients had been over- or under-treated at initial surgery. The clinical factors examined were not significantly associated with higher risk of malignancy in IC patients.

CONCLUSION

This study highlights the potential for improved preoperative diagnosis to streamline decision making for surgical management of patients with thyroid nodules.

Temporal analysis of thyroid cancer management in a Melbourne tertiary centre

BACKGROUND

The American Thyroid Association (ATA) management guidelines for thyroid cancer were revised in 2009. The aim of this study was to determine if management of thyroid cancer in our institution has changed in accordance with the introduction of the revised ATA guidelines (ATA²⁰⁰⁹ ), and to compare the characteristics and management of thyroid cancer in a Melbourne endocrine surgery unit over a 7-year period.

METHODS

All patients treated by the Monash University Endocrine Surgery Unit for thyroid cancer between 2007 and 2013 were divided into two groups - the pre-ATA²⁰⁰⁹ group (2007-2010) and the post-ATA²⁰⁰⁹ group (2011-2013). Comparisons were made of the demographics, cytology, pathology, surgical outcome and adjuvant therapy using t-test and chi-squared tests.

RESULTS

There were 333 patients in the pre-ATA²⁰⁰⁹ group and 342 patients in the post-ATA²⁰⁰⁹ group. Fewer non-diagnostic fine-needle aspiration cytology results were identified in the post-ATA²⁰⁰⁹ group (4% versus 0.9%; P = 0.01), while the rates of other fine-needle aspiration cytology categories were similar. There was a reduction in the use of radioactive iodine ablation in the post-ATA²⁰⁰⁹ group, both in the proportion of patients being treated (66% versus 48%; P < 0.001) and the dosages used (mean 96 mCi versus 80 mCi; P < 0.01), despite similar tumour size in both groups.

CONCLUSION

The key changes in practice thought to be attributable to the 2009 revised ATA guidelines were the reduction in the use and dosage of radioactive iodine in the management of differentiated thyroid cancer.

Synoptic pathology reporting for thyroid cancer: a review and institutional experience

Thyroid cancer surgical pathology reports contain information that is critical for diagnosis, determining completeness of resection, staging and guiding postoperative management. Traditional narrative pathology reporting is prone to errors and omissions with variability in content and completeness. The objective of this review was to evaluate the impact of synoptic reporting on thyroid cancer pathology reporting. Our institutional study of pathology reporting of differentiated thyroid cancers at a Canadian tertiary care institution relative to the College of American Pathologists checklists is also presented and critically evaluates deficiencies in the narrative pathology reporting format.

Introducing the reporting system for thyroid fine-needle aspiration cytology according to the new guidelines of the Japan Thyroid Association

The Japan Thyroid Association (JTA) recently published new guidelines for clinical management of thyroid nodules. This paper introduces their diagnostic system for reporting thyroid fine-needle aspiration cytology. There are two points where the new reporting system that differs from existing internationally-accepted ones. The first is the subclassification of the so-called indeterminate category, which is divided into 'follicular neoplasm' and 'others'. The second is the subclassification of follicular neoplasm into 'favor benign', 'borderline' and 'favor malignant'. It is characterized by self-explanatory terminologies as to histological type and probability of malignancy to establish further risk stratification as well as to facilitate communication between clinicians and cytopathologists. The different treatment strategies adopted for thyroid nodules is deeply influenced by the particular diagnostic system used for thyroid cytology. In Western countries all patients with follicular neoplasms are advised to have immediate diagnostic surgery while patients in Japan often undergo further risk stratification without immediate surgery. The JTA diagnostic system of reporting thyroid cytology is designed for further risk stratification of patients with indeterminate cytology. If a surgeon applies diagnostic lobectomy to all patients with follicular neoplasm unselectively, this subclassification of follicular neoplasm has no practical meaning and is unnecessary. Cytological risk stratification of follicular neoplasms is optional and cytopathologists can choose either a simple 6-tier system without stratification of follicular neoplasm or a complicated 8-tier system depending on their experience in thyroid cytology and clinical management.

Hemithyroidectomy is the preferred initial operative approach for an indeterminate fine needle aspiration biopsy diagnosis

BACKGROUND

Fine needle aspiration biopsy represents the critical initial diagnostic test used for evaluation of thyroid nodules. Our objectives were to determine the cytological distribution, the utility of clinicopathologic characteristics for predicting malignancy and the true proportion of cancer among individuals who presented with indeterminate cytology and had undergone thyroid surgery for suspicion of cancer.

METHODS

We retrospectively reviewed 1040 consecutive primary thyroid operations carried out over an 8-year period at a tertiary care endocrine referral centre. Follicular neoplasm (FN), Hürthle cell neoplasm (HN), neoplasms suspicious for but not diagnostic of papillary carcinoma (IP) and neoplasms with cellular atypia (IA) were reviewed.

RESULTS

In all, 380 individuals presented with cytologically indeterminate thyroid nodules. Of these, 252 (66%) patients had FN, 47 (12%) HN, 44 (12%) IP, 26 (7%) IA and 11 (4%) had mixed diagnoses. Biopsied lesions were found to be malignant on pathological evaluation in 102 (27%) patients: 49 (19%) with FN, 11 (23%) HN, 28 (64%) IP and 9 (35%) with IA. Hemithyroidectomy was adequate definitive treatment in 196 of 225 (87%) patients with FN and 39 of 42 (93%) with HN. Significant associations with a cancer diagnosis were identified for smaller tumour size in patients with FN (p = 0.004) and right thyroid lobe location in patients with IP (p = 0.012), although these factors were nonsignificant in the corrected analyses for multiple comparisons.

CONCLUSION

In a review of the experience at a Canadian centre, 4 operations were carried out to identify each cancer, and hemithyroidectomy was the optimal initial and definitive surgical approach for most patients.

The role of fine-needle aspiration cytology in the surgical management of thyroid cancer

BACKGROUND

Diagnosis of thyroid malignancy relies on clinical assessment, imaging and fine-needle aspiration cytology 'FNAC' of thyroid nodules. The purpose of this study was to evaluate how effective synoptically reported FNAC is in clinical practice in diagnosing thyroid cancer. We also examined the effectiveness of using preoperative FNAC results to plan the type of operation for treating thyroid cancer.

METHOD

A retrospective case series of all patients undergoing thyroid surgery from 1993 to 2008 was analysed. All data were collected prospectively and recorded in a dedicated endocrine surgery database. Data analysed included age, sex, preoperative FNAC result, type of surgery, final histology and complications. Cytology was reported based on a five-tiered classification system.

RESULTS

There were 1373 patients in total and 125 patients with a final diagnosis of thyroid cancer. Female to male ratio was 3:1. Cytology reported as 'malignant' was confirmed as thyroid cancer in 100% of the cases. Of the patients, 47% with 'suspicious' cytology report and 14% with 'follicular/indeterminate' cytology report had a final diagnosis of cancer. Thyroid cancer subtypes were 90 patients with papillary thyroid cancer 'PTC', 24 with follicular 'FTC', eight with medullary 'MTC' and two with anaplastic cancer. Cytology was suggestive of cancer in 89% of the patients with PTC >10 mm, 75% with FTC and 88% with MTC. Transient hypocalcaemia was the commonest complication occurring in 7.2%. There were no cases of permanent hypoparathyroidism. Recurrent laryngeal nerve neuropraxia occurred in 2.4% with a permanent palsy occurring in 0.8%. There were three cancer-related deaths.

CONCLUSIONS

Preoperative synoptically reported FNAC is effective when used in diagnosing and planning surgery for thyroid cancer.

Evidence-based evaluation of the risks of malignancy predicted by thyroid fine-needle aspiration biopsies

A National Cancer Institute (NCI) "Thyroid Fine-Needle Aspiration (FNA) State of the Science Conference" recently proposed standardized nomenclature and "risks of malignancies" associated with various diagnostic categories. We evaluated the evidence levels of the data used by NCI to predict malignancy risks and whether those estimates had clinical validity in our patient population.Eight hundred seventy-nine patients underwent thyroid FNA during 2006. FNA diagnoses were translated into NCI diagnostic categories, and 2-year follow-up retrospective information was obtained. Four percentages of malignancies were calculated for each diagnostic category using follow-up information from FNA, thyroidectomy, both, and all patients as denominators. 95% confidence intervals (CI) were estimated for all proportions, and results were analyzed with chi-square statistics. "Relative risk" calculations were performed using the percentage of malignancies in the entire population under study as a denominator.Most of the studies cited by the NCI provided incomplete and variable level III evidence based mainly on surgical follow-up. Among our patients, the percentages of malignancies calculated with follow-up data from all patients as the denominator were similar to the "risk estimates" proposed by the NCI, but estimates based on surgical follow-up overestimated the probability of thyroid malignancy for patients with FNA diagnosis of "benign" and "follicular lesions of undetermined significance" (FLUS). Relative risk and 95% CI calculations suggested that the NCI classification could be simplified into three categories: "benign," "FLUS + neoplasm," and "suspicious + malignant."

Guidelines for the reporting of nongynecologic cytopathology specimens

CONTEXT

Gynecologic cytology terminology and report formatting have been nationally standardized since the implementation of The Bethesda System of 1988, but standard reporting for nongynecologic cytology has never been formally addressed on the same scale.

OBJECTIVES

To promote patient safety through uniform reporting in nongynecologic cytology (including fine-needle aspiration cytology) and to improve communication between laboratories and health care providers.

DATA SOURCES

Sources include the College of American Pathologists Cytopathology Resource Committee; the College of American Pathologists Council on Scientific Affairs Ad Hoc Committee on Pathology Report Standardization; the College of American Pathologists Laboratory Accreditation Program inspection checklists; the Joint Commission for Accreditation of Healthcare Organizations; and the Clinical Laboratory Improvement Amendments of 1988.

CONCLUSIONS

We describe the major elements of quality nongynecologic cytology reporting and discuss areas of controversy in cytology reporting. Standardized nongynecologic specimen reporting will expand the concept of common report elements already widely implemented in gynecologic cytology reporting. The intent is to improve communication with the health care team while remaining in compliance with federal mandates and accreditation guidelines.

Usefulness of a synoptic data tool for reporting of head and neck neoplasms based on the College of American Pathologists cancer checklists

The primary source of information that clinicians use when evaluating and managing patients with cancer is the surgical pathology report. Omission of critical information from the report is a recognized problem in pathology, especially considering the expanding amount of information, such as molecular diagnostics data, that is now routinely included in reports. To standardize surgical pathology reports, the College of American Pathologists (CAP) introduced the CAP checklists. In 2004, the American College of Surgeons Commission on Cancer mandated that 90% of pathology reports indicating a cancer diagnosis at participating centers contain all scientifically validated or regularly used data elements. The University of Pittsburgh Medical Center has implemented synoptic reporting based on the CAP checklists for all major tumor types. We report our experience with synoptic reporting on head and neck neoplasms, demonstrating, in particular, how this can be customized according to needs of each institution.

Management of the solitary thyroid nodule

Thyroid nodules are common, with up to 8% of the adult population having palpable nodules. With the use of ultrasound, up to 10 times more nodules are likely to be detected. Increasing numbers of nodules are being detected serendipitously because of the rising use of imaging to investigate unrelated conditions. The primary aim in investigating a thyroid nodule is to exclude the possibility of malignancy, which occurs in about 5% of nodules. This begins with a thorough history, including previous exposure to radiation and any family history of thyroid cancer or other endocrine diseases. Clinical examination of the neck should focus on the thyroid nodule and the gland itself, but also the presence of any cervical lymphadenopathy. Biochemical assessment of the thyroid needs to be followed by thyroid ultrasound, which may demonstrate features that are associated with a higher chance of the nodule being malignant. Fine-needle aspiration biopsy is crucial in the investigation of a thyroid nodule. It provides highly accurate cytologic information about the nodule from which a definitive management plan can be formulated. The challenge remains in the management of nodules that fall under the "indeterminate" category. These may be subject to more surgical intervention than is required because histological examination is the only way in which a malignancy can be excluded. Surgery followed by radioactive iodine ablation is the mainstay of treatment for differentiated thyroid cancers, and the majority of patients can expect high cure rates.