Multiple Beau's Lines

A 69-year-old man was referred for the evaluation of changes to his fingernails that developed after the initiation of chemotherapy with docetaxel–cisplatin–fluorouracil for gastric cancer. Physical examination revealed multiple white lines on the fingernails, known as Beau's lines.
The lines corresponded to the start of each chemotherapy cycle, with the distance between the lines proportional to the interval between the cycles.
One white line showed less severe dystrophia than the others (arrow); on reviewing the medical records, it was noted that the corresponding chemotherapy cycle consisted of docetaxel–fluorouracil only, owing to the patient's compromised renal function at the time, whereas all the other cycles consisted of the complete docetaxel–cisplatin–fluorouracil regimen.

Cytotoxic chemotherapeutic agents can induce the temporary arrest of proliferative function of the nail matrix, which may be manifested as multiple Beau's lines in the nail plate. This nail pattern can provide insight into the interval between and intensity of chemotherapy cycles.