Сравнение несравнимого: методологические проблемы исследований хирургических стратегий лечения больных раком прямой кишки с синхронными метастазами в печени

ЦЕЛЬ: систематический анализ ключевых методологических проблем, возникающих при сравнении хирургических стратегий лечения больных раком прямой кишки (РПК) с изолированными синхронными резектабельными метастазами в печени.

ПАЦИЕНТЫ И МЕТОДЫ: проведен поиск в базах PubMed/MEDLINE, Cochrane Library, Scopus, Elibrary (2000– 2026 гг.). Включены исследования, сравнивавшие две и более хирургические стратегии при РПК с синхронными метастазами в печени; методологические работы; рандомизированные клинические исследования (РКИ); проспективные и ретроспективные когортные исследования; метаанализы.

РЕЗУЛЬТАТЫ: выявлены следующие основные методологические ограничения проанализированных исследований: систематическая ошибка отбора (пациенты с разной распространённостью опухоли направляются на разные стратегии); систематическая ошибка времени выживания (immortal time bias) при этапных подходах; асимметрия сравнения осложнений (одна операция против двух операций); гетерогенность схем системной и лучевой терапии; проблема незавершения лечения (до 35% при liver-first); смешение популяций рака ободочной и прямой кишки; ограничения псевдорандомизации; отсутствие крупных РКИ. Предложены пути решения: прагматические и регистровые РКИ, эмуляция целевого исследования (TTE), стратификация по объёму резекции печени, режиму неоадъювантной терапии и молекулярному профилю, стандартизация отчётности (STROBE, TARGET).

ЗАКЛЮЧЕНИЕ: существующие методологические проблемы существенно ограничивают интерпретацию данных. Окончательные выводы о превосходстве какой-либо хирургической стратегии преждевременны. Необходимы исследования с более строгим дизайном и коррекцией смещений.

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