How the On­co­type DX® test’s pre­dic­tive util­i­ty pro­pelled pre­ci­sion on­col­o­gy 

In 2003, Kather­ine Y., a 53-year-old po­di­a­trist, found a lump in her breast dur­ing a self-ex­am. The fog of a can­cer di­ag­no­sis fol­lowed: back-to-back ap­point­ments, scans and pathol­o­gy re­ports, a new, can­cer-cen­tric vo­cab­u­lary to learn. Kather­ine un­der­went a dou­ble mas­tec­to­my to re­move the can­cer, then faced her hard­est de­ci­sion yet: Should she have chemother­a­py to re­duce the chance of can­cer re­turn­ing some­where else in her body?

Stan­dard tu­mor as­sess­ments sug­gest­ed chemother­a­py would be nec­es­sary, and Kather­ine heard the fa­mil­iar log­ic: treat broad­ly, treat ag­gres­sive­ly, re­duce risk. But she al­so un­der­stood how chemother­a­py could neg­a­tive­ly im­pact her qual­i­ty of life. What she need­ed was clar­i­ty.

In Jan­u­ary 2004, Kather­ine be­came the first com­mer­cial pa­tient to re­ceive the On­co­type DX Breast Re­cur­rence Score® test. She had a Re­cur­rence Score® re­sult of 18 — a low score in­di­cat­ing she like­ly would not ben­e­fit from chemother­a­py. That num­ber wasn’t just da­ta — it was a turn­ing point for Kather­ine and for the more than 2 mil­lion pa­tients that have used the On­co­type DX test since then.

The im­me­di­ate ben­e­fit was per­son­al and pro­found: Kather­ine avoid­ed months of tox­ic treat­ment and the long tail of pos­si­ble side ef­fects. Twen­ty-two years lat­er, Kather­ine re­mains can­cer-free*. To­day, she and her hus­band, Mel — both re­tired — spend their time ski­ing, bik­ing, and hik­ing in the Sier­ras with their dog, Crit­ter.

“I feel so blessed I had the op­por­tu­ni­ty to be the first to take this test, forego chemother­a­py, and learn my po­ten­tial for dis­tant re­cur­rence. Very im­por­tant­ly, I want­ed to help oth­er women learn about this test so they could have a say in their own, tai­lored can­cer treat­ment,” Kather­ine, who is now an On­co­type DX Pa­tient Am­bas­sador, re­cent­ly shared.

Kather­ine’s sto­ry il­lus­trates the hu­man side of pre­ci­sion on­col­o­gy: per­son­al­ized treat­ment plans, few­er side ef­fects, pre­served qual­i­ty of life, and — most im­por­tant­ly — peace of mind. When you mul­ti­ply the ef­fect of a bet­ter de­ci­sion across mil­lions of pa­tients, the sto­ry be­comes more than clin­i­cal — it high­lights the eco­nom­ic val­ue of the test.

Af­ter more than two decades of clin­i­cal ev­i­dence and re­al-world use in more than 100 coun­tries, more than two mil­lion breast can­cer pa­tients¹ and their care teams have used the On­co­type DX test to help guide their de­ci­sion-mak­ing. The On­co­type DX Breast Re­cur­rence Score test de­liv­ers per­son­al­ized ge­nom­ic re­sults to help guide treat­ment de­ci­sions for pa­tients with ear­ly-stage HR+, HER2- breast can­cer. Twen­ty-two years af­ter launch, the On­co­type DX Breast Re­cur­rence Score test is the on­ly ge­nom­ic test proven to pre­dict chemother­a­py ben­e­fit from ran­dom­ized con­trolled stud­ies², guid­ing per­son­al­ized treat­ment de­ci­sions with the high­est lev­el of ev­i­dence.

Prog­nos­tic and pre­dic­tive tests serve very dif­fer­ent pur­pos­es; prog­nos­tic tests pro­vide in­sight in­to how can­cer may be­have over time — such as the like­li­hood of re­cur­rence — but they do not pro­vide in­for­ma­tion about treat­ment ben­e­fits. Pre­dic­tive bio­mark­ers, on the oth­er hand, help de­ter­mine whether a pa­tient is like­ly to ben­e­fit from a spe­cif­ic ther­a­py, in­for­ma­tion that can di­rect­ly guide treat­ment choice and sup­port more in­di­vid­u­al­ized care.³

When a test can pre­dict chemother­a­py ben­e­fit and safe­ly re­duce its use, there are both clin­i­cal and fi­nan­cial ben­e­fits. By iden­ti­fy­ing who is — and is not — like­ly to ben­e­fit, the test has en­abled clin­i­cians and pa­tients to de-es­ca­late treat­ment con­fi­dent­ly.  An es­ti­mat­ed 1.6 mil­lion⁴ of the 2 mil­lion pa­tients test­ed world­wide may have been spared from po­ten­tial­ly un­nec­es­sary chemother­a­py, avoid­ing the acute and long-term tox­i­c­i­ties of treat­ment.

Chemother­a­py is ex­pen­sive, but its true cost ex­tends be­yond treat­ment ac­qui­si­tion. There are in­fu­sion vis­its, sup­port­ive med­ica­tions, man­age­ment of side ef­fects, as well as emer­gency vis­its and ad­mis­sions for com­pli­ca­tions. There are al­so in­di­rect bur­dens: di­min­ished qual­i­ty of life, time away from work, care­giv­er strain, trav­el costs, and pro­duc­tiv­i­ty loss­es.

Us­ing a pub­lished eco­nom­ic mod­el, it is es­ti­mat­ed that use of the On­co­type DX test to in­form ad­ju­vant treat­ment de­ci­sions among HR+, HER2- pa­tients re­sult­ed in av­er­age life­time sav­ings of ap­prox­i­mate­ly $10,000 per pa­tient in the U.S. health­care sys­tem. Us­ing the pub­lished eco­nom­ic mod­el, based on cur­rent treat­ment pat­terns, it is es­ti­mat­ed that use of the On­co­type DX test to in­form ad­ju­vant treat­ment de­ci­sions among HR+, HER2- pa­tients (com­pared to clin­i­cal-patho­log­i­cal fac­tors alone) could have saved more than $14 bil­lion to the U.S. health­care sys­tem since the in­tro­duc­tion of the test.

A re­cent large, re­al-world analy­sis⁵ of pa­tients with ear­ly-stage HR+, HER2- breast can­cer demon­strat­ed that chemother­a­py uti­liza­tion in­creas­es ap­pro­pri­ate­ly with high­er Re­cur­rence Score re­sults in the U.S., con­sis­tent with guide­line-based care. The On­co­type DX test strength­ens de­ci­sion con­sis­ten­cy among providers, un­der­scor­ing its val­ue not on­ly in guid­ing in­di­vid­ual care but al­so in har­mo­niz­ing ex­pert judg­ment in rou­tine prac­tice, in­clud­ing across all racial and eth­nic groups. The On­co­type DX Breast Re­cur­rence Score test’s per­for­mance has been con­sis­tent­ly val­i­dat­ed across di­verse pop­u­la­tions, and this analy­sis found that chemother­a­py use was gen­er­al­ly con­sis­tent across racial and eth­nic groups⁶, sug­gest­ing eq­ui­table ap­pli­ca­tion of Re­cur­rence Score re­sult-guid­ed treat­ment rec­om­men­da­tions.

The On­co­type DX test has been avail­able in­ter­na­tion­al­ly since 2010, so the glob­al health eco­nom­ics im­pact of this test is im­mea­sur­able. But com­pelling da­ta points ex­ist; a re­cent study pre­sent­ed at the San An­to­nio Breast Can­cer Sym­po­sium (SABCS) in 2025 found that the On­co­type DX test sig­nif­i­cant­ly in­flu­enced ad­ju­vant treat­ment de­ci­sions, pri­mar­i­ly lead­ing to chemother­a­py de-es­ca­la­tion and strength­en­ing de­ci­sion con­sis­ten­cy among Swiss breast can­cer spe­cial­ists⁷. An­oth­er analy­sis pre­sent­ed at the same con­gress es­ti­mat­ed that On­co­type DX test­ing in node-pos­i­tive pa­tients across five on­col­o­gy cen­ters in Ire­land over an 11-year pe­ri­od led to sav­ings of more than €60 mil­lion to the Irish health­care sys­tem⁸. This was cal­cu­lat­ed by specif­i­cal­ly iden­ti­fy­ing pa­tients who did not un­der­go chemother­a­py, thus avoid­ing di­rect med­ical costs and broad­er so­ci­etal bur­dens.

For more than two decades, clin­i­cians and pa­tients have re­lied on the On­co­type DX test to move be­yond one-size-fits-all care and use pre­dic­tive in­sights to make more con­fi­dent, in­di­vid­u­al­ized de­ci­sions. With that con­fi­dence comes some­thing pa­tients and their physi­cians val­ue deeply: the abil­i­ty to pur­sue the right treat­ment plan for them. The en­dur­ing qual­i­ty of the On­co­type DX test has en­abled those de­ci­sions and brought clar­i­ty when it was need­ed the most.

The life sci­ences in­dus­try's largest-ever pri­vate in­vest­ment fund has ar­rived, and it comes from the world's biggest al­ter­na­tive as­set man­ag­er.

On Mon­day, Black­stone an­nounced it had raised $6.3 bil­lion for its lat­est life sci­ences in­vest­ment fund, Black­stone Life Sci­ences VI. The huge fundraise is equal to more than half the val­ue of new in­vest­ment funds raised in all of 2025, ac­cord­ing to a year-end re­port from bankers at William Blair.

Nick Galakatos, glob­al head of Black­stone Life Sci­ences, said the fundrais­ing ef­forts had ben­e­fit­ed from some of the un­cer­tain­ty in mar­kets, in Wash­ing­ton, and around the globe, de­scrib­ing it as a "com­pli­cat­ed mar­ket on many fronts."