Modified systemic inflammation score for prediction of malignancy in indeterminate thyroid nodules- an effective tool in low-resource settings!

Shreyamsa Manjunath; Devarbhavi Praveen Kumar

doi:10.1530/endoabs.99.P566

Background: About 20% of thyroid-nodules have indeterminate-cytology (IDC), classified as Bethesda categories-III/ IV. They carry varying risks of malignancy (6-18%, 10-40% respectively). Ideal test to determine the risk of malignancy in IDC is unclear. Molecular-profiling has shown promise, but availability & affordability is an issue. We aim to evaluate diagnostic value of modified systemic inflammation score(mSIS) to determine malignancy in IDC.

Methodology: Retrospective study of 79 patients with IDC thyroid-nodules at Maax Superspecialty Hospitals (Shivamogga, India), from January/2022-October/2023. Patients with thyroiditis, active-infections, hematologic, immuno-rheumatological, recurrent thyroid cancer or other co-morbidities excluded. Pre-operative hematology records were exmanined. Albumin(Alb) & lymphocyte-monocyte ratio(LMR) calculated and variables that may affect the development of malignancy studied.

Patients were divided into 3 groups:

mSIS-0: Alb >/= 4.0 g/ dL, LMR </= 3.4

mSIS-1: Alb <4.0 g/ dL OR LMR <3.4

mSIS-2: Alb <4.0 g/ dL, LMR <3.4

Relationship between mSIS and postoperative pathology, and the diagnostic value of mSIS was investigated.

Results: F:M=70:9. Mean age of patients was 35.8 (+/-9.076). The mean nodule size was 3.15 (+/-1.08)cm. 45 (57%) were Bethesda-III and 34 (43%) nodules were Bethesda-IV. Overall, of the 79 patients, 39 had benign nodules (BN), while 40 had malignant nodules(MN). Among MN, 25 were PTC, 5 FTC, 8 FVPTC & 2 were papillary microcarcinoma. There was no significant difference in baseline parameters in either groups. Mean LMR in BN group was 5.023 (+/-1.45), while that in MN group was 3.11 (+/-0.66). With a p-value=0.001, difference was significant. Mean albumin in BN group was 4.61 (+/-0.49) and MN group was 3.63 (+/-0.48). The difference was significant (p-value:0.001). Twenty nodules each in Bethesda-III( 45%) and Bethesda-IV (59%) were malignant. 61% in mSIS-1, 92.8% in mSIS-2 were malignant. When risk-stratified for mSIS-1 and mSIS-2 groups, it showed a sensitivity-71.8%, specificity-97.5%, PPV-96.6%, NPV-79.6%.


		mSIS-0(n=30)	mSIS-1(n=21)	mSIS-2(n=28)	p-value
Bethesda-III	Benign	19	5	1	0.001
	Malignant	1(5.2%)	6(54.5%)	13(93%)
Bethesda-IV	Benign	10	3	1	0.012
	Malignant	0	7(70%)	13(93%)

Conclusions: mSIS-1 & mSIS-2 groups carry high risk of malignancy. Though not a substitute, mSIS is a cost-effective & easy to perform test when molecular-profiling is not possible. It can help in selecting appropriate patients for surgical management

Endocrine Abstracts

P566