TABLE 1.
Demographic and clinicopathologic factors of the study population
| All patients n = 77 (%) |
RP/pelvic LN disappearance n = 33 (43) |
RP/Pelvic LN persistence n = 44 (57) |
p value | |
|---|---|---|---|---|
| Age at diagnosis (median, IQR) | 56 (49–63) | 57 (49–63) | 54 (47–63) | .40 |
| Sex | ||||
| Male | 35 (45) | 16 (48) | 19 (43) | .64 |
| Female | 42 (55) | 17 (52) | 25 (57) | |
| Race | ||||
| White | 63 (82) | 24 (72) | 39 (89) | .18 |
| Black | 12 (16) | 8 (24) | 4 (9) | |
| Other | 2 (2) | 1 (3) | 1 (2) | |
| Functional status | ||||
| Independent | 75 (98) | 32 (100) | 43 (98) | .35 |
| Partially dependent | 1 (2) | 0 (0) | 1 (2) | |
| Pretreatment stage (AJCC 8th ed) | ||||
| I | 2 (2) | 1 (5) | 0 (0) | .31 |
| II | 2 (2) | 1 (5) | 0 (0) | |
| III | 50 (96) | 20 (90) | 30 (100) | |
| Pretreatment tumor location | ||||
| Lower rectum | 34 (47) | 12 (41) | 22 (51) | .70 |
| Middle rectum | 34 (47) | 15 (52) | 19 (44) | |
| Upper rectum | 4 (6) | 2 (7) | 2 (5) | |
| Neoadjuvant chemotherapy | ||||
| No | 39 (95) | 11 (100) | 28 (93) | .95 |
| Yes | 2 (5) | 0 (0) | 2 (7) | |
| Neoadjuvant chemoradiation | ||||
| No | 0 (0) | 0 (0) | 2 (6) | .97 |
| Yes | 40 (52) | 11 (100) | 29 (94) | |
| Total neoadjuvant therapy | ||||
| No | 42 (55) | 11 (33) | 31 (71) | <.01 |
| Yes | 35 (46) | 22 (67) | 13 (29) | |
| Operation type | ||||
| LAR | 47 (61) | 22 (67) | 25 (57) | .52 |
| APR | 30 (39) | 11 (33) | 19 (43) | |
| Approach | ||||
| Open | 32 (42) | 14 (42) | 18 (41) | .89 |
| Minimally invasive | 45 (58) | 19 (58) | 26 (59) | |
| # Positive mesorectal LN, pretreatment (median, IQR) | 2 (1–5) | |||
| # Positive RP LN, pretreatment (median, IQR) | 0 (0–1) | |||
| # Positive pelvic LN, pretreatment (median, IQR) | 1 (1–2) | |||
| # Positive RP + pelvic LN, pretreatment (median, IQR) | 1 (1–2) | |||
| # Positive mesorectal LN, posttreatment (median, IQR) | 1 (0–2) | |||
| # Positive RP LN, posttreatment (median, IQR) | 0 (0) | |||
| # Positive pelvic LN, posttreatment (median, IQR) | 1 (0–2) | |||
| # Positive RP + pelvic LN, posttreatment (median, IQR) | 1 (1–2) | |||
| Adjuvant chemotherapy | ||||
| No | 9 (22) | 2 (20) | 7 (23) | .99 |
| Yes | 32 (78) | 8 (80) | 24 (77) | |
| Adjuvant chemoradiation | ||||
| No | 39 (95) | 10 (100) | 29 (94) | .99 |
| Yes | 2 (5) | 0 (0) | 2 (6) | |
| Tumor differentiation | ||||
| Well | 1 (2) | 1 (4) | 0 (0) | .35 |
| Moderate | 50 (85) | 21 (84) | 29 (85) | |
| Poor | 7 (12) | 2 (8) | 5 (15) | |
| Undifferentiated | 1 (2) | 1 (4) | 0 (0) | |
| Pathologic response after NAT | ||||
| No response | 11 (15) | 4 (13) | 7 (17) | .10 |
| Partial response | 50 (70) | 19 (61) | 31 (76) | |
| Complete response | 11 (15) | 8 (26) | 3 (7) | |
| Pathologic stage (AJCC 8th ed) | ||||
| 0 | 11 (14) | 9 (26) | 2 (5) | .10 |
| I | 14 (20) | 6 (19) | 8 (20) | |
| II | 17 (30) | 7 (23) | 10 (26) | |
| III | 29 (41) | 10 (32) | 19 (49) | |
| Final margin status | ||||
| R0 | 71 (92) | 32 (97) | 39 (88) | .35 |
| R1 | 6 (8) | 1 (3) | 5 (11) | |
| LVI | ||||
| No | 60 (85) | 25 (81) | 35 (88) | .67 |
| Yes | 11 (15) | 6 (19) | 5 (12) | |
| PNI | ||||
| No | 51 (81) | 21 (81) | 30 (81) | .85 |
| Yes | 12 (19) | 5 (19) | 7 (19) | |
| Follow-up in months (median, IQR) | 19 (12–45) | 16 (12–34) | 23 (15–55) | .50 |
Abbreviations: AJCC, American Joint Committee on Cancer; LAR, low anterior resection; APR, abdominoperineal resection; IQR, interquartile range; LN, lymph node; LVI, lymphovascular invasion; PNI, perineural invasion; RP, retroperitoneum.