The 44-year-old woman had been employed by Deutsche Post for 23 years. Last summer she was having cancer treatment and came back to work while she was still undergoing chemotherapy.
Unpleasant side-effects caused her to take small breaks. These included going into a pharmacy to use the toilet, going home to drain lymphatic fluid and a chemotherapy appointment that ran over time, the Westdeutsche Allgemeine Newspaper reported on Thursday.
Deutsche Post said that this was classed as missing work unjustifiably and allegedly strong-armed her into signing a termination contract.
They had her followed on her delivery rounds in the summer of 2013 – thought not to be uncommon practice in the company, colleagues told the woman.
She said that she signed the termination contract because she was under so much pressure from management to do so, the paper reported.
Afterwards, she took her dismissal to a North Rhine Westphalian labour court and filed an unfair dismissal claim.
Bosses believed they thought they had enough evidence to sack her and presented the court with photos of her at home, or entering the pharmacy, during work hours, the newspaper reported.
Yet judges have now said that the termination contract was invalid, and said that she can have her job back. She will also receive full pay from when she was sacked.
The woman, who has not been named, told the court that she believes Deutsche Post had an ulterior motive for being so inflexible about her illness.
She was hired 23 years ago and remains on a contract which sees her earning a lot more than other post couriers.