MODIFIED SYSTEMIC INFLAMMATION SCORE FOR PREDICTION OF MALIGNANCY IN INDETERMINATE THYROID NODULES- AN EFFECTIVE TOOL IN LOW-RESOURCE SETTINGS!

AUTHORS:
S. Manjunath (Shivamogga, India) , P.K. Devarbhavi (Shivamogga, India)
Background:
About 20% of thyroid-nodules have indeterminate-cytology (IDC), classified as Bethesda categories-III/ IV. They carry varying risks of malignancy(ROM, 6-18%, 10-40% respectively). Ideal test to determine ROM 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.
Methods:
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, other co-morbidities excluded. Albumin(Alb) & lymphocyte-monocyte ratio(LMR) calculated and variables that may affect the development of malignancy studied. Patients divided into 3 groups: mSIS-0: Alb >/= 4.0 g/ dL, LMR
Results:
F:M=70:9. Mean age- 35.8(+/-9.076), mean nodule size- 3.15(+/-1.08)cm. 45(57%) were Bethesda-III, 34(43%) Bethesda-IV. 39 nodules were benign(BN), while 40 malignant(MN) (PTC-25, FTC-5, FVPTC-8, microPTC-2). No statistical-difference in baseline parameters between groups. Mean LMR: BN-5.023(+/-1.45), MN-3.11(+/-0.66) (p-value:0.001). Mean albumin: BN-4.61(+/-0.49), MN-3.63(+/-0.48) (p-value:0.001). Total nodules in mSIS-0=30,mSIS-1=21,mSIS-2=28. In Bethesda-III group- mSIS-0(19-benign,1-malignant),mSIS-1(5-benign,6-malignant),mSIS-2(1-benign,13-malignant),p-value=0.001. In Bethesda-IV group- mSIS-0(10-benign),mSIS-1(3-benign,7-malignant),mSIS-3(1-benign,13-malignant),p-value=0.012. 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%.
Conclusions:
mSIS-1,mSIS-2 groups carry high ROM. Though not a substitute, mSIS is a cost-effective, easy to perform test when molecular-profiling is not possible.