Prosigna Messy Journey

 You could not find 81520 in the 2017 PAMA data because it was not yet the Prosigna code. The test was reported under 0008M during the PAMA data-collection period. CPT 81520 replaced 0008M effective January 1, 2018.

Prosigna pricing chronology

Year	Code	Medicare CLFS rate	What happened
2016	0008M	$3,419.42	New Prosigna MAAA code; priced identically to 81519, confirming the Oncotype DX crosswalk
2017	0008M	$3,443.36	Inflation-adjusted pre-PAMA national limitation amount
2018	81520	$3,099.02	0008M replaced by 81520; first PAMA reduction, capped at 10%
2019	81520	$2,789.12	Second 10% reduction
2020	81520	$2,510.21	Third 10% reduction
2021–2023	81520	$2,510.21	Further reductions postponed by Congress

The arithmetic is exact:

• $3,443.36 × 90% = $3,099.02

• $3,099.02 × 90% = $2,789.12

• $2,789.12 × 90% = $2,510.21

The remarkable answer: its PAMA target was $900

CMS’s original 2018 PAMA calculation table, under 0008M, reports:

• 2017 CLFS rate: $3,443.36

• Private-payor weighted median: $900.00

• Nominal reduction: 73.86%

• 2018 phase-in rate: $3,099.02

• 2019 phase-in rate: $2,789.12

• 2020 phase-in rate: $2,510.21

Thus, $3,099 and $2,510 were not the PAMA target prices. They were transitional prices descending toward an underlying PAMA weighted median of only $900. Congressional freezes interrupted the descent after 2020.

Bottom line

Your recollection of the structure was right but the code changed in the middle:

Prosigna was originally priced as 0008M, crosswalked to Oncotype DX code 81519. Its 2017 rate was $3,443.36. PAMA produced a startling weighted-median target of only $900, but statutory phase-in protection limited the reductions to 10% annually. When 0008M became 81520 in 2018, the price history transferred with it.

The roughly $3,800 figure does not appear as a national CLFS amount in the CMS files I checked; it may have been an earlier MolDX/local allowed amount, list price, or commercial reimbursement figure. The documented national sequence begins at $3,419.42 in 2016, rising to $3,443.36 in 2017.

Official CMS materials: 2016 CLFS file, 2017 CLFS file, 2018 CLFS file, and 2018 PAMA payment-rate files.

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