% IMPORTANT: The following is UTF-8 encoded. This means that in the presence % of non-ASCII characters, it will not work with BibTeX 0.99 or older. % Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or % “biber”. @ARTICLE{Ballhausen:304245, author = {A. Ballhausen and F. Morano and A. Stahler and S. Lonardi and A. J. Kind and C. Cremolini and S. Swoboda and G. Randon and D. Horst and M. Prisciandaro and A. H. S. Alig and C. C. Pircher and A. Jarosch and P. Andena and A. Kurreck and A. A. Chiaramonte and S. Stintzing$^*$ and F. Pietrantonio and D. P. Modest$^*$ and A. Raimondi}, title = {{P}rimary tumor sidedness and negative hyperselection to modulate anti-{EGFR}-based maintenance strategies in patients with {RAS} wild-type metastatic colorectal cancer: individual patient data pooled analysis of two randomized clinical trials.}, journal = {British journal of cancer}, volume = {nn}, issn = {0007-0920}, address = {Edinburgh}, publisher = {Nature Publ. Group}, reportid = {DKFZ-2025-01799}, pages = {nn}, year = {2025}, note = {epub}, abstract = {Patients with RAS wild-type (WT), left-sided metastatic colorectal cancer (mCRC), negatively hyperselected for anti-EGFR resistance alterations, benefit most from anti-EGFR-based first-line treatment. The predictive impact of these stratification parameters on maintenance strategy efficacy is unclear.This pooled analysis included individual patient data from the PanaMa (NCT01991873) and Valentino (NCT02476045) phase 2 trials. Patients with RAS WT mCRC received FOLFOX plus Panitumumab induction therapy followed by maintenance with 5-fluorouracil/leucovorin (5-FU/LV) plus Panitumumab vs. 5-FU/LV monotherapy (PanaMa) or Panitumumab monotherapy (Valentino). Outcomes included progression-free survival (PFS) and overall survival (OS). Subgroup analyses examined primary tumor sidedness (left vs. right) and hyperselection status (negative vs. altered).Among 607 patients receiving induction, sidedness and hyperselection status were available for 589 and 511 patients, respectively. Left-sided and negative hyperselected tumors were observed in $80.2\%$ and $63.9\%$ of patients, respectively. Panitumumab-based maintenance improved PFS in left-sided, negative hyperselected patients compared to 5-FU/LV alone, with no OS differences. PFS and OS were comparable for Panitumumab alone vs. Panitumumab plus 5-FU/LV.Tumor sidedness and hyperselection status significantly influence maintenance strategy efficacy in mCRC. For left-sided, negative hyperselected patients, Panitumumab monotherapy may optimize efficacy while minimizing toxicity. Further investigation into the relative contribution of individual hyperselection parameters in this setting is warranted.}, cin = {BE01}, ddc = {610}, cid = {I:(DE-He78)BE01-20160331}, pnm = {899 - ohne Topic (POF4-899)}, pid = {G:(DE-HGF)POF4-899}, typ = {PUB:(DE-HGF)16}, pubmed = {pmid:40877636}, doi = {10.1038/s41416-025-03164-5}, url = {https://inrepo02.dkfz.de/record/304245}, }