TG and neoplasm: The current study found that ∼50% of TgAb+ DTC patients had no Tg detected by IMA or MS—a percentage comparable to a recent study (40) but higher than our previous study (33), lending support to the practice of following the TgAb trend as a surrogate tumor marker (3, 4, 42, 43) or remeasuring Tg by RIA methodology.