Question: when using the tnm system for staging what does the m stand for
[{'answer': 'M describes distant metastasis', 'provenance': [{'wikipedia_id': '574223', 'title': 'TNM staging system', 'start_paragraph_id': 5, 'start_character': 12, 'end_paragraph_id': 5, 'end_character': 42, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '574223', 'title': 'TNM staging system', 'start_paragraph_id': 5, 'start_character': 0, 'end_paragraph_id': 5, 'end_character': 97, 'bleu_score': 0.8702397637697911, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9554627983819006481}, 'section': 'Section::::Abstract.'}]}]