The Ethical Implications of the Reclassification of Noninvasive Follicular Variant Papillary Thyroid Carcinoma

"Your cancer is no longer considered cancer": Psychological reactions to reclassification information and communication preferences

Objective

In 2016, the encapsulated follicular variant of papillary thyroid carcinoma (EFVPTC) was reclassified as noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP). This reclassification removed the word "carcinoma" and the definition of cancer from the diagnosis. While the nomenclature change was expected to psychologically impact patients, that question has not been systematically explored. Using qualitative methods, we aimed to explore the psychological impact of reclassification on thyroid cancer patients and their preferences for receiving reclassification information.

Methods

Semi-structured interviews with nine non-EFVPTC thyroid cancer survivors were conducted. Participants were presented with a hypothetical reclassification scenario, and interview transcripts were analyzed using a thematic content analytic approach.

Results

Participants expressed a range of psychological reactions to reclassification information, primarily negative, including anger, mistrust, and uncertainty, but also relief. All participants expressed difficulty understanding the concept of reclassification. Communication preferences favored conversation with an established medical provider over written materials, such as a letter.

Discussion and conclusion

Communication must align with patient preferences. Being mindful of potential negative psychological reactions when providing information on cancer reclassification is vital.

Innovation

This study examines reactions to cancer reclassification information and preferences for how this information should be communicated.

Reclassification as non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP): A retrospective review in a single institution and outcome study

Background/Aim: Since non-invasive follicular thyroid neoplasm (NIFTP) was first defined in 2016, past overtreatment status, impact for the risk of malignancy, and incidence of NIFTP have been the subject of study. Retrospective cohort studies have been published and present widely varying results in different geographic regions. This study aimed to reclassify follicular variants of papillary thyroid carcinoma (FVPTC) cases diagnosed in a single center using the defined stringent NIFTP criteria and to determine incidence, clinicopathological features, and survival of NIFTP cases. Methods: This retrospective cohort study was conducted in a single center and consisted of patients with diagnosed follicular variant papillary thyroid carcinoma in thyroidectomy/thyroid lobectomy specimens between 2014 and 2021. Reports of FVPTC cases between 2014 and 2018 were evaluated by two experienced pathologists to identify candidates for NIFTP. Archived glass slides of the potential NIFTP cases were retrieved and reviewed independently by two pathologists.  Results: Between 2014 and 2021, 84 patients who underwent surgery were diagnosed with FVPTC. Reports of 49 patients diagnosed before 2018 were re-evaluated by two pathologists, and 20 cases were identified as candidates for NIFTP. After blind evaluation of pathology slides, five cases (10%) were diagnosed as NIFTP according to the criteria established before 2016, and two cases between 2016 and August 2018 were still diagnosed as NIFTP. Fourteen patients were diagnosed with NIFTP between 2014 and 2021. The median follow-up of the NIFTP patients was 4.3 years, and no recurrence and/or metastasis was reported. Conclusion: NIFTP represents 7.6% of the papillary thyroid carcinoma (PTC) cases in our cohort, which is higher than the incidence rate in our country. The follow-up results of our cases were uneventful considering the indolent nature of NIFTP, but we had high thyroidectomy rates. Due to the concomitant PTC, multifocality, and uncertainties in the follow-up routine, we think it would be appropriate for these patients to remain in active follow-up.

Non-Invasive Follicular Thyroid Neoplasm with Papillary-Like Nuclear Features Is Not a Cytological Diagnosis, but It Influences Cytological Diagnosis Outcomes: A Systematic Review and Meta-Analysis

BACKGROUND

A low-risk thyroid tumour, non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) was introduced in 2016. NIFTP criteria require a thorough histological examination to rule out capsular and lymphovascular invasion, which denies the possibility of preoperative cytological diagnosis. Nevertheless, since the adoption of the new entity, the cytology of NIFTP has been a subject of interest.

OBJECTIVES

The present systematic review and meta-analysis investigate the cytological diagnosis of NIFTP.

METHOD

An online PubMed literature search was conducted between March 1, 2020, and June 30, 2020, for all original articles considering the cytology of histologically proven NIFTP. The studies including data on fine needle aspiration specimens classified by The Bethesda System for Reporting Thyroid Cytology (TBSRTC) categories, risk of malignancy (ROMs) in the TBSRTC categories, and cytomorphological features of NIFTP were included in the meta-analysis. Non-English studies and case reports were excluded. The data were tabulated and statistical analysis was performed with Open Meta-Analyst program.

RESULTS

Fifty-eight studies with a total of 2,553 NIFTP cases were included in the study. The pooled prevalence of NIFTP cases was calculated among 25,892 surgically resected cases from 20 studies and the results show that NIFTP consisted 4.4% (95% confidence interval [CI]: 3.5-5.4%) of all cases. Most of the NIFTP cases (79.0%) belonged to the intermediate categories of TBSRTC. The pooled distribution of NIFTP cases in each TBSRTC category was 1.3% (95% CI: 0.8-1.7%) in non-diagnostic (ND), 8.9% (95% CI: 6.9-10.8%) in benign, 29.2% (95% CI: 25.0-33.4%) in atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS), 24.2% (95% CI: 19.6-28.9%) in follicular neoplasm (FN), 19.5% (95% CI: 16.1-22.9%) in suspicious for malignancy (SM), and 6.9% (95% CI: 5.2-8.7%) in malignant. Compared to pre-NIFTP era, the pooled risk differences of ROM were reduced by 2.4% in ND, 2.7% in benign, 8.2% in AUS/FLUS, 8.2% in FN, 7.3% in SM, and 1.1% in the malignant category. The cytomorphological features of NIFTP were similar to follicular variant of papillary thyroid carcinoma (FVPTC) but lesser to papillary thyroid carcinoma (PTC).

CONCLUSIONS

Based on our results, NIFTP remains a histological diagnosis. Although cytomorphological features cannot be used in differentiating NIFTP from FVPTC, they may guide in separating NIFTP from PTC. Features such as papillae, microfollicles, giant cells, psammoma bodies, and the amount of papillary-like nuclear features should be taken into account when suspicious of NIFTP. NIFTP should not have papillae or psammoma bodies, and giant cells were rarely observed.

The Incidence of Noninvasive Follicular Thyroid Neoplasm with Papillary-Like Nuclear Features: A Meta-Analysis Assessing Worldwide Impact of the Reclassification

Background: Noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) reclassification has significantly influenced the field of thyroidology. However, the extent of this impact depends upon the incidence of NIFTP in a given population. In this meta-analysis, we aimed to obtain robust information about the actual incidence of NIFTP worldwide by reviewing the published data. Methods: Comprehensive literature search was performed using electronic databases of PubMed and Web of Science over a five-year period (January 1, 2016, to January 30, 2021). The incidence of NIFTP was calculated by dividing the number of NIFTPs by the number of papillary thyroid carcinomas (PTCs). Meta-analysis of proportion and their 95% confidence interval [CI] were pooled using the random-effect model. Heterogeneity across the included studies was assessed using I² statistics. Egger's regression test and funnel plot of estimates were used to evaluate the publication bias. p-Value <0.05 was considered significant. Results: From 505 publications, we included 50 studies, all retrospective, with 100,780 PTCs and 3990 NIFTP from 92 institutions worldwide. The overall incidence of NIFTP was 6.0% [CI 4.4-8.2] among PTCs or thyroid malignancies with a high level of heterogeneity among the included studies (I² = 98.6%). NIFTP incidence was largely similar in North America and Europe (9.3% vs. 9.6%), with a significantly lower overall rate in Asia (2.1%). There was a significant decline in the reported incidence of NIFTP in non-Asian studies published after 2017 (p = 0.002). On applying our data on global thyroid cancer statistics, this reclassification would affect ∼30,881 patients annually, with a lower impact in Asia compared with North America and Europe. Conclusions: This comprehensive meta-analysis confirms that the worldwide NIFTP incidence is much lower than estimated initially. The NIFTP rates are significantly lower in Asian compared with North American and European countries. Apart from geography, NIFTP rates are significantly influenced by the nature of study, type of database used for sample collection, and the diagnostic criteria used. Introduction of NIFTP may potentially spare over 30,000 patients worldwide annually from clinical and psychological consequences of a thyroid cancer diagnosis.

Noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) is rare, benign lesion using modified stringent diagnostic criteria: Reclassification and outcome study

BACKGROUND

Rigid diagnostic criteria for NIFTP have been recently proposed. The frequency of NIFTP using the new criteria is unknown, and whether abortive papillae are associated with BRAF^V600E mutation has not been studied. The aim of this study is to identify NIFTP by a retrospective review of Follicular Variant of Papillary Thyroid Carcinoma (FVPTC), and to study its incidence as well as the association between immunohistochemical BRAF^V600E expression and abortive papillae in NIFTP.

DESIGN

Thyroid tumors diagnosed as FVPTC or NIFTP over a period of 18 years (2000-2017) were identified using the laboratory information system. The final pathology reports were reviewed and potential NIFTP were retrieved. The archived slides for these cases were independently reviewed by 2 pathologists. BRAF^V600E (clone: VE1) immunostain was performed on representative tumor blocks. Clinical information including follow-up data was obtained from the electronic medical records.

RESULTS

Among the 1918 cases with the diagnosis of papillary thyroid carcinoma (PTC), 589 (30.7%) of FVPTC and 136 cases of potential NIFTP were identified. After the review of the archived pathology slides, 29 lesions were morphologically reclassified as NIFTP. Four (13.7%) of these were positive for BRAF^V600E; no association was found between the presence of abortive papillae and BRAF^V600Eexpression (p=0.3). Exclusion of the 4 cases with BRAF^V600Eexpression resulted in 25 lesions of final NIFTP, representing 4.2% of the FVPTC and 1.3% of the PTC. The mean age of the NIFTP patients was 50 years, 87.5% were females. The mean size of the lesions was 1.4 cm (0.1-4.0 cm). Intranuclear pseudoinclusions were not identified, and abortive papillae were identified in 60% of NIFTP. The average follow-up was 70 (28-166) months. There were no adverse events (recurrence or metastasis) in the NIFTP group.

CONCLUSION

When strictly defined, NIFTP comprises 1.3% of cases perviously classified as PTC. In morphological NIFTP, no correlation is found between the presence of abortive papillae and the BRAF^V600E expression. Intranuclear pseudo-inclusions are not observed in NIFTP. Modification of current morphological criteria to include BRAF^V600E immunohistochemistry test may stratify NIFTP with benign outcome.

Reclassification as NIFTP: a Retrospective Review in a Single Institution with an Emphasis on Workload

The aim of this study was to determine the number of cases of papillary thyroid carcinoma (PTC) which could be reclassified as non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) in our institute over a 10-year period, document their clinical status and assess the number of slides that had to be reviewed per case to exclude NIFTP. The histopathology reports for thyroid resections for all papillary carcinoma over a 10-year period (2007-2016) were reviewed. Five hundred forty-five histopathology reports were reviewed, and 71 cases were identified as potential cases of NIFTP. Forty-nine (69%) cases had been referred from external departments and the slides were not available for review. Of the remaining 22 (31% of 71) cases, 5 were reclassified as NIFTP. The 17 cases that were not reclassified as NIFTP required review of 114 of 356 slides (median 5.5 slides per case) was required to exclude NIFTP. For the 5 NIFTP cases, 58 slides were reviewed (median 12 slides per case). We found that review of the histology reports alone was adequate for exclusion in most cases, e.g. classic PTC or EVPTC cases with documented lymphovascular invasion or capsular invasion. As a single exclusion criterion is required for exclusion from reclassification as NIFTP, this can be achieved efficiently. Two of the five patients received radioactive iodine [RAI] as per standard treatment at time of diagnosis, on the basis of tumour size. None have recurrent or metastatic disease with mean follow-up of 5.8 years.

A user's guide to non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP)

The term non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) was recently introduced to replace a subset of follicular variant of papillary thyroid carcinoma (FVPTC). The goal of this change was to promote more conservative management of these tumours and spare patients the psychological burden of a cancer diagnosis. The histological diagnosis of NIFTP is stringent: the tumour needs to demonstrate encapsulation or circumscription, a purely follicular architecture and the presence of nuclear features of papillary thyroid carcinoma, while lacking capsular and vascular invasion, a significant component of solid growth and high-grade features (increased mitotic activity and necrosis). In order to ensure that these inclusion and exclusion criteria are met, the tumour must be sampled extensively, with the entire capsule/periphery submitted in all cases. When sampled by fine-needle aspiration, NIFTP is usually classified within the indeterminate categories of the Bethesda System for Reporting Thyroid Cytopathology. NIFTP is characterized genetically by frequent RAS mutations, although rarely other alterations, such as the BRAF K601E mutation and gene rearrangements in PPARG or THADA, may occur. In this review, we will examine the history of FVPTC and the findings and factors that culminated in the introduction of the NIFTP terminology. A discussion will follow with the histological, cytological and molecular characteristics of NIFTP. We will conclude by considering the potential impact of the introduction of the NIFTP terminology.

Evaluating the projected surgical impact of reclassifying noninvasive encapsulated follicular variant of papillary thyroid cancer as noninvasive follicular thyroid neoplasm with papillary-like nuclear features

BACKGROUND

The reclassification of noninvasive encapsulated follicular variant of papillary thyroid cancer to noninvasive follicular thyroid neoplasm with papillary-like nuclear features will reduce nonefficacious and potentially harmful care. Reclassification is estimated in 18.6% of patients with papillary thyroid carcinoma; we aimed to quantify the implications of this change.

METHODS

Pathology reports from April 2006 to April 2016 were reviewed to isolate cases that would have been designated as neoplasm with papillary-like nuclear features. Of the 1,335 cases of papillary thyroid carcinomas, 194 cases (14.5%) met criteria. Cases in which neoplasm with papillary-like nuclear features was found in combination with other thyroid malignancies (n = 25) and cases of prior thyroid lobectomy (n = 5) were excluded. Demographic, pathologic, treatment, and follow-up data were assessed for the remaining 164 potential neoplasm with papillary-like nuclear features cases. Logistic regression analysis was performed to evaluate association between fine-needle aspiration result and index procedure.

RESULTS

Of the 164 patients with tumors who met neoplasm with papillary-like nuclear features criteria, fine-needle aspiration results were nondiagnostic (2%), benign (18%), atypia/follicular lesion of undetermined significance (26%), follicular neoplasm or suspicious for follicular neoplasm (20%), suspicious for malignancy (19%), malignant (6%), and not obtained (9%). Eighty-five (52%) patients underwent total thyroidectomy. A "suspicious for malignancy" fine-needle aspiration result was associated with undergoing total thyroidectomy versus thyroid lobectomy (P = .006). Thyroid lobectomy was the index procedure for 79 patients (48%); of these patients, 54% (n = 43, 3.2% of all patients with papillary thyroid carcinomas) underwent subsequent total thyroidectomy, and 24% received postoperative radioactive iodine treatment. There were no recurrences among the 125 patients with >3 months of follow-up.

CONCLUSION

The reclassification of noninvasive encapsulated follicular variant of papillary thyroid cancer as neoplasm with papillary-like nuclear features will decrease nonefficacious treatment and reduce costs. However, the impact of this change with regard to extent of surgery was limited to 3.2% of patients with papillary thyroid carcinomas compared with the projected potential impact on 18.6%.

The Flip Side of NIFTP: an Increase in Rates of Unfavorable Histologic Parameters in the Remainder of Papillary Thyroid Carcinomas

The term noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) was recently proposed to replace noninvasive follicular variant of papillary thyroid carcinoma (FVPTC) both to promote more conservative management of these tumors and spare patients the psychological burden of a cancer diagnosis. This reclassification will lower the incidence of papillary thyroid carcinoma (PTC). In addition, it could result in an increase in the rates of unfavorable histologic prognosticators for PTC overall because NIFTPs had previously accounted for many of the PTCs without these features. Our aim was to evaluate the potential impact of the reclassification of NIFTP on the rates of extrathyroidal extension, lymphovascular invasion, and lymph node metastases in PTC. We identified all PTCs clinically over 1 cm diagnosed on surgical resection between August 2010 and August 2012. The histopathologic characteristics, including PTC subtype, tumor size, presence of extrathyroidal extension and lymphovascular invasion, and surgical margin and lymph node status were all recorded. Based on these parameters, cases were classified according to the American Thyroid Association (ATA) risk stratification system for structural disease recurrence. Tumor slides for cases initially diagnosed as FVPTC were reviewed to identify tumors that would now be classified as NIFTPs. Our cohort included 348 cases of PTC, of which 94 (27%) would now be classified as NIFTPs. After excluding NIFTPs from the PTC category, there were increased rates of extrathyroidal extension (26% up from 19%, p = 0.046), lymphovascular invasion (37% up from 27%, p = 0.0099), and lymph node metastases (26% up from 19%, p = 0.045) among the remaining PTCs. Based on these changes in histologic features, 10% fewer cases were defined as ATA low risk (62% down from 72%, p = 0.0081). Our results indicate that the downgrading of some carcinomas to NIFTP will increase the rates of higher risk histologic parameters in the remaining PTCs by statistically significant margins. Although the overall survival for PTC is very high and would likely not be changed significantly by the introduction of NIFTP, additional studies evaluating the impact of the NIFTP shift are warranted.

Noninvasive Follicular Thyroid Neoplasm with Papillary-Like Nuclear Features: Historical Context, Diagnosis, and Future Challenges

The encapsulated/well-demarcated non-invasive form of follicular variant of papillary thyroid carcinoma (FVPTC) that occurs annually in 45,000 patients worldwide was thought for 30 years to be a carcinoma. Many studies have now shown almost no recurrence in these non-invasive tumors, even in patients treated by surgery without radioactive iodine therapy. The categorization of the tumor as cancer has led to aggressive forms of treatment, with their side effects, financial costs, and the psychological and social impact of a cancer diagnosis. Recently, the encapsulated/well-demarcated non-invasive, FVPTC was renamed as noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) by an international group of experts. The new terminology lacks the carcinoma label enabling clinicians to avoid aggressive therapy. By taking the reader through the history of FVPTC, this article explains how diagnostic criteria for thyroid carcinoma of follicular cells have evolved over the last 60 years. It discusses the steps that led to the labeling of FVPTC as cancer and highlights the various studies that helped reclassify and rename this tumor. It also sheds light on the impact of this reclassification on cytologic diagnosis and focuses on the studies needed to refine and expand the histologic criteria of NIFTP. By understanding the history of this change in nomenclature, future classification of tumors will be greatly improved.