{"id":"b407d62b-3e87-5e23-be56-e91da37ce497","stable_key":"cb568d28-484a-5c2e-9fcc-2d780358e514:c-oral-colorectal-survival-null","predicate":"did_not_improve_colorectal_cancer_survival","statement":"Vitamin C showed no survival advantage over placebo in the advanced colorectal cancer trial.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"10c5978e-d328-52bc-bbe5-826fed0d12a1","mechanism_event_label":"The historical randomized trial did not show longer survival for its regimen.","subject":{"id":"2047867f-9872-53b2-a553-71c911d0695b","slug":"ascorbic-acid","display_name":"L-Ascorbic acid","entity_type_key":"small_molecule"},"object":{"id":"b248f818-62c2-51f5-b29b-41b8fd5f782e","slug":"colorectal-cancer-overall-survival","display_name":"Overall survival in colorectal cancer","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"10c5978e-d328-52bc-bbe5-826fed0d12a1","stable_key":"cb568d28-484a-5c2e-9fcc-2d780358e514:c-oral-colorectal-survival-null-event","event_type":"observed_intervention","label":"The historical randomized trial did not show longer survival for its regimen.","description":"Vitamin C showed no survival advantage over placebo in the advanced colorectal cancer trial.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"2047867f-9872-53b2-a553-71c911d0695b","slug":"ascorbic-acid","display_name":"L-Ascorbic acid","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"b248f818-62c2-51f5-b29b-41b8fd5f782e","slug":"colorectal-cancer-overall-survival","display_name":"Overall survival in colorectal cancer","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"experimental_model","value_text":"Double-blind randomized trial: 100 advanced colorectal cancer patients without previous cytotoxic chemotherapy.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Oral vitamin C 10 g/day versus placebo. The 1985 abstract does not specify route; route is cross-checked in Chen2005 Introduction, which identifies the two oral randomized trials through references 5 and 6.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Different cancer, route and cointerventions from modern IV combination trials; not a direct test of their mechanism.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin C research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-c","display_name":"Vitamin C","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The historical randomized trial did not show longer survival for its regimen.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[c-moertel1985] High-dose vitamin C versus placebo in the treatment of patients with advanced cancer who have had no prior chemotherapy. A randomized double-blind comparison (1985). https://pubmed.ncbi.nlm.nih.gov/3880867/ DOI: 10.1056/nejm198501173120301","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"route_provenance","value_text":"Oral route cross-checked in Chen2005 Introduction and reference 6 (Moertel1985): https://pmc.ncbi.nlm.nih.gov/articles/PMC1224653/ . Clinical outcomes come from the Moertel abstract.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Human blood or whole-person endpoints","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"c77def4d-0877-5581-8d3d-558cebe7fbba","evidence_kind":"source_excerpt","locator":"Lines 1767-1778","start_line":1767,"end_line":1778,"excerpt":"### c-oral-colorectal-survival-null\nVitamin C showed no survival advantage over placebo in the advanced colorectal cancer trial.\nCondition category: normal\nnutrient_topic: Vitamin C research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The historical randomized trial did not show longer survival for its regimen.\norganism: Homo sapiens\ntissue_or_cell_type: Human blood or whole-person endpoints\nexperimental_model: Double-blind randomized trial: 100 advanced colorectal cancer patients without previous cytotoxic chemotherapy.\nlimitations: Different cancer, route and cointerventions from modern IV combination trials; not a direct test of their mechanism.\nexposure: Oral vitamin C 10 g/day versus placebo. The 1985 abstract does not specify route; route is cross-checked in Chen2005 Introduction, which identifies the two oral randomized trials through references 5 and 6.\nroute_provenance: Oral route cross-checked in Chen2005 Introduction and reference 6 (Moertel1985): https://pmc.ncbi.nlm.nih.gov/articles/PMC1224653/ . Clinical outcomes come from the Moertel abstract.\n[c-moertel1985] High-dose vitamin C versus placebo in the treatment of patients with advanced cancer who have had no prior chemotherapy. A randomized double-blind comparison (1985). https://pubmed.ncbi.nlm.nih.gov/3880867/ DOI: 10.1056/nejm198501173120301","model_system":"Double-blind randomized trial: 100 advanced colorectal cancer patients without previous cytotoxic chemotherapy.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [c-moertel1985] High-dose vitamin C versus placebo in the treatment of patients with advanced cancer who have had no prior chemotherapy. A randomized double-blind comparison (1985). https://pubmed.ncbi.nlm.nih.gov/3880867/ DOI: 10.1056/nejm198501173120301","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"fa811221-13bd-5c10-adc1-eaf097c7703c","stable_key":"import-cb568d28-484a-5c2e-9fcc-2d780358e514","title":"Vitamin C: mechanisms, deficiency and nutrient interactions (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"b7fd83f956abb81855f2ea23199ba14e465cd91f4a2ac560277ec21ddafd7bfc","revision_id":"6cde9bbb-d712-5746-82a6-85b144253efa","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}