fiona_VT said:

My prescriber wanted a baseline TSH and did not want a calcitonin, and I would like to understand the reasoning rather than just accepting it.

Thyroid cancer screening labs for thyroid monitoring — addressing the boxed warning concern with actual data:

Calcitonin level: 3.0 pg/mL (normal <10). Checked at baseline, month 6, and month 12. Rock stable, no upward trend.

Thyroid ultrasound: normal, no nodules at month 12.

The MTC risk from rodent studies has not been confirmed in human post-marketing data across millions of patient-years. The boxed warning is a regulatory precaution based on animal data. While monitoring is prudent, the clinical risk appears to be negligible.

TirzTom said:

Thyroid cancer screening labs for thyroid monitoring — addressing the boxed warning concern with actual data: Calcitonin level: 3.0 pg/mL (normal…

Agreed, and one caution: a single measurement is not a measurement. Anything that moves day to day needs a trend before it means anything at all.

fiona_VT said:

My prescriber wanted a baseline TSH and did not want a calcitonin, and I would like to understand the reasoning rather than just accepting it.

This is my experience too, for whatever a second data point is worth.

Clinical perspective, offered as context rather than as advice. It helps to say which part of this you are uncertain about. A precise question gets a precise answer; a general one gets everybody’s favourite anecdote.