Transcript Follicular Variant of Papillary Thyroid Carcinoma

It’s Not Cancer:
FOLLICULAR VARIANT OF
PAPILLARY THYROID CARCINOMA
Winchester Kwok, Princess Margaret Hospital
“An international panel of doctors has decided that a type of
tumor that was classified as a cancer is not a cancer at all.”
Encapsulated follicular variant of papillary thyroid carcinoma
was rename as noninvasive follicular thyroid neoplasm with
papillary-like nuclear features, or Niftp, which pronounced as
“Nift-P”
Background
 On March 8–9, 2012, the National Cancer
Institute convened a conference
 Problem of cancer overdiagnosis
 When tumors that would otherwise not
become symptomatic are identified and
treated.
 When this overdiagnosis is not recognized,
it can lead to overtreatment.
Esserman, L. J. (2014). Lancet Oncol.. Addressing overdiagnosis and overtreatment in cancer: a prescription for change, 15 .
Ca thyroid
 Yearly incidence has nearly tripled from 1975 to 2009
 Yet death rate remained constant
 25%of the new thyroid cancers diagnosed in 1988–
1989 were <=1cm compared with 39% of the new
thyroid cancer diagnoses in 2008–2009
 Prevalence of palpable thyroid nodule 1-5% vs. USG
19-68%
 Increase in incidence attributed to the rapid growth
of ultrasound and fine-needle aspiration use
Haugen, B. R. (2015). THYROID. 2015 American Thyroid Association Management Guidelines for Adult Patients with
Thyroid Nodules and Differentiated Thyroid Cancer, 26 (1).
Differentiated Ca Thyroid
 Papillary thyroid tumor (75-85%)

- arise from follicular cells with
papillary architecture
- more than 10 microscopic
variants
 Follicular thyroid tumor (10-20%)
Follicular variant of papillary Ca thyroid
 2nd most common
subtype variant
 ~4.9-41.2% of PTC
 Encapsulated or non
encapsulated;
invasive or non
invasive
 Diagnosis could have
interobserver
difference
Jug, R. (2016). Papillary carcinoma Non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP). Retrieved October 1, 2016
from http://www.pathologyoutlines.com/topic/thyroidglandNIFTP.html
36 studies published from 2003-2014 was reviewed
Comparing FVPTC and classical PTC
FVPTC was associated with statistically significant less
- extrathyroid extension
- lymph node metastasis
FVPTC had more indolent behavior and
likely a genetically distinct entity from
- recurrence
classical papillary Ca thyroid
- BRAF mutation
A study published in 2006
69 patient with FVPTC
Median follow up: 10.8 years
recurrence:1
distant metastasis: 0
In a subgroup of patient
(n=31) with non invasive
encapsulated FVPTC treated
with lobectomy only without
RAI
recurrence/ lymph node
metastasis: 0
Liu, J. (2006). Follicular Variant of Papillary Thyroid
Carcinoma A Clinicopathologic Study of a Problematic Entity.
CANCER, 107(6).
- Published in 4/2016
-Retrospective study by The Endocrine Pathology Society working group including
28 pathologists/ endocrinologists/ surgeons from 7 countries and 4 continents
-Total 268 encapsulated follicular variant of papillary thyroid carcinoma (EFVPTC)
from 13 institutions
- Divided into 2 groups:
group 1: non invasive EFVPTC treated with surgery only without RAI
group 2: EFVPTC with vascular invasion +- tumor capsule invasion
-109 patient with
non invasive
EFVPTC treated
without RAI
-median 13.0 (1026) years of follow
up
-Adverse events: 0
Scanned slides were
reviewed and new
diagnostic criteria was
published
Revision of nomenclature
Encapsulated follicular variant of papillary thyroid carcinoma
 Noninvasive Follicular Thyroid Neoplasm with Papillary-like
Nuclear Features (NIFTP)
What are the clinical
implications?
Due to a great degree of cytological difficulty in interpretation, >90% of
EFVPTC was put into Bethesda Categories III/ IV/ V during initial FNAC
cytology report
In the Past…
By BTA guidelines:
NIFTP with size >=4cm
or size 1-4cm
By ATA guidelines
NIFTP with size >=4cm
 RAI +- Completion
thyroidectomy
X RAI No longer indicated
In the Present…
-Decrease the use of RAI +- completion thyroidectomy and
related complications
-Decrease psychological impact to patient with diagnosis of
cancer
-Decrease need for long term surveillance
-Decrease overall cost of health care surveillance
(Based on US cost, no RAI alone would save ~$5000-$8500/ patient)
-~45000 patient per year worldwide
Nikiforov, Y. E. (2016). Nomenclature Revision for
Encapsulated Follicular Variant of Papillary Thyroid
Carcinoma A Paradigm Shift to Reduce Overtreatment of
Indolent Tumors. JAMA Oncology, 2 (8).
Perros, P. (2014). British Thyroid Association Guidelines for the Management of Thyroid
Cancer. CLINICAL ENDOCRINOLOGY, 81 .
In the future…
-Training and update of pathologists
-More updated guidelines will be needed for
clinicians
- Increase global awareness of cancer overdiagnosis
and efforts in reviewing current clinicopathology
diagnosis in lesions with indolent behaviors
Take Home Message
- Encapsulated follicular variant of papillary thyroid
carcinoma no longer considered as malignant lesions
Renamed as noninvasive follicular thyroid neoplasm with
papillary-like nuclear features
-Problem of nowadays worldwide
medical care: overdiagnosis of cancer
and over treatment
“First - do - harm”
Questions are welcome
Reference
1. Esserman, L. J. (2014). Lancet Oncol.. Addressing overdiagnosis and
overtreatment in cancer: a prescription for change, 15 .
2. Haugen, B. R. (2015). THYROID. 2015 American Thyroid Association
Management Guidelines for Adult Patients with Thyroid Nodules and
Differentiated Thyroid Cancer, 26 (1).
3. Jug, R. (2016). Papillary carcinoma Non-invasive follicular thyroid neoplasm
with papillary-like nuclear features (NIFTP). Retrieved October 1, 2016 from
http://www.pathologyoutlines.com/topic/thyroidglandNIFTP.html
4. Yang, J. (2015). Comparison of the clinicopathological behavior of the
follicular variant of papillary thyroid carcinoma and classical papillary thyroid
carcinoma: A systematic review and meta-analysis. MOLECULAR AND
CLINICAL ONCOLOGY, 3
5. Liu, J. (2006). Follicular Variant of Papillary Thyroid Carcinoma A
Clinicopathologic Study of a Problematic Entity. CANCER, 107(6).
6. Nikiforov, Y. E. (2016). Nomenclature Revision for Encapsulated Follicular
Variant of Papillary Thyroid Carcinoma A Paradigm Shift to Reduce
Overtreatment of Indolent Tumors. JAMA Oncology, 2 (8).
7. Perros, P. (2014). British Thyroid Association Guidelines for the Management
of Thyroid Cancer. CLINICAL ENDOCRINOLOGY, 81 .
8. Kolata, G. (2016, April 14). It’s Not Cancer: Doctors Reclassify a Thyroid
Tumor. The New York Times
European consensus for the management of patients with
differentiated thyroid carcinoma of the follicular epithelium 2006