Hertha Berlin winger Jean-Paul Boetius has been diagnosed with a testicular tumour.
The 28-year-old from the Netherlands will take an indefinite break from football to undergo further tests and treatment after a urological examination on Wednesday discovered the tumour.
Hertha coach Fredi Bobic said: 'As bitter as this news is at first, we are full of hope and confidence that Jean-Paul will recover and return to our circle as soon as possible.
'Until his return, he will receive every conceivable support from us. We will be close together as the Hertha family and wish him only the best.'
The former Feyenoord, Basel and Mainz player joined Hertha on a free transfer at the beginning of August, signing a three-year contract.
He has featured in all six Bundesliga fixtures since arriving, making the starting line-up for two and coming off the bench in the other four, playing largely as a central attacking midfielder.
The Berlin club are currently 13th in the table, having won one, drawn three and lost three of their seven matches to date.
Boetius is the fourth Bundesliga player to be diagnosed with a testicular tumour this year.
His Hertha team-mate Marco Richter was diagnosed with a malignant growth earlier in the year but it was identified early enough to be removed through surgery without the need for chemotherapy.
Richter returned to action in the Bundesliga at the end of August.
Union Berlin defender Timo Baumgartl returned to action in Sunday's 2-0 win over Wolfsburg after being diagnosed back in April. Surgery removed the tumour and he received a course of chemotherapy.
And Borussia Dortmund striker Sebastien Haller was found to have the same issue during a pre-season training camp in Switzerland after the new signing from Ajax complained of feeling ill.
Haller said in an interview late last month he was feeling 'really good' after starting chemotherapy but is expected to be sidelined for 'several months.'