Twenty-seven cohort studies (n=1,232) were included in the review.
The authors noted variability between the studies in terms of reporting of signs and symptoms, definition of IBC, treatment regimens, and method of determining and reporting pCR. If an assessment of statistical heterogeneity was carried out as part of the meta-analysis, its results were not reported.
No anthracycline induction: the pCR was 4% (95% confidence interval, CI: 1, 18; 2 studies, n=42); 3- and 5-year DFS were 38% (95% CI: 15, 69; 3 studies, n=57) and 44% (95% CI: 29, 60; 2 studies, n=39), respectively; 3- and 5-year OS were 47% (95% CI: 9, 88; 2 studies, n=43) and 60% (95% CI: 39, 79; 1 study, n=25), respectively.
Low-dose anthracycline-based induction: the pCR was 11% (95% CI: 7, 17; 8 studies, n=317); 3- and 5-year DFS were 45% (95% CI: 40, 50; 14 studies, n=698) and 37% (95% CI: 31, 43; 11 studies, n=622), respectively; 3- and 5-year OS were 61% (95% CI: 52, 68; 12 studies, n=662) and 47% (95% CI: 38, 56; 11 studies, n=630), respectively.
Moderate-dose anthracycline-based induction: the pCR was 14% (95% CI: 8, 22; 3 studies, n=97); 3- and 5-year DFS were 45% (95% CI: 34, 56; 2 studies, n=76) and 38% (95% CI: 30, 50; 2 studies, n=76), respectively; 3- and 5-year OS were 69% (95% CI: 59, 78; 3 studies, n=91) and 52% (95% CI: 36, 68; 3 studies, n=91), respectively.
HDC before surgery: the pCR was 32% (95% CI: 24, 41; 3 studies, n=123); 3- and 5-year DFS were 58% (95% CI: 39, 75; 3 studies, n=133) and 38% (95% CI: 18, 62; 1 study, n=21), respectively; 3- and 5-year OS were 71% (95% CI: 62, 78; 3 studies, n=133) and 62% (95% CI: 38, 82; 1 study, n=21), respectively.
HDC after surgery: 3- and 5-year DFS were 62% (95% CI: 53, 70; 4 studies, n=116) and 56% (95% CI: 42, 69; 3 studies, n=86), respectively; 3- and 5-year OS were 72% (95% CI: 59, 82; 4 studies, n=116) and 53% (95% CI: 31, 73; 3 studies, n=86), respectively.
HDC, combined: 3- and 5-year DFS were 59% (95% CI: 50, 68; 7 studies, n=249) and 52% (95% CI: 39, 65; 4 studies, n=107), respectively; 3- and 5-year OS were 70% (95% CI: 64, 76; 7 studies, n=249) and 55% (95% CI: 38, 71; 4 studies, n=107), respectively.