Table 1.
Clinicopathological Characteristics of Rectal Neuroendocrine Tumors at Diagnosis
| Characteristics | Study population (n=41) | LN (–) (n=21) | LN (+) (n=20) | p-value* |
|---|---|---|---|---|
| Age, mean±SD, yr | 48.73±12.64 | 52.05±12.29 | 45.25±12.34 | 0.085† |
| Sex | 0.062‡ | |||
| Male | 27 (65.9) | 11 (52.4) | 16 (80.0) | |
| Female | 14 (34.1) | 10 (47.6) | 4 (20.0) | |
| Carcinoid symptoms | 0.488§ | |||
| Present | 2 (4.9) | 2 (9.5) | 0 | |
| Absent | 39 (95.1) | 19 (90.5) | 21 (100) | |
| Tumor size, mean±SD, mm | 8.26±2.98 | 7.19±2.64 | 9.60±2.78 | 0.007† |
| Tumor size, mm | 0.008§ | |||
| 0–5 | 6 (14.6) | 6 (28.6) | 0 | |
| 6–10 | 28 (68.3) | 14 (66.7) | 14 (70.0) | |
| 11–15 | 7 (17.1) | 1 (4.8) | 6 (30.0) | |
| Tumor location (distance from anal verge), mean±SD, mm | 6.46±2.15 | 6.24±2.14 | 6.70±2.18 | 0.498† |
| Depth of invasion | 0.107§ | |||
| Mucosa | 1 (2.4) | 0 | 1 (5.0) | |
| Submucosa | 38 (92.7) | 21 (100) | 17 (85.0) | |
| Muscularis propria | 2 (4.9) | 0 | 2 (10.0) | |
| Ki-67 index, % | 0.027§ | |||
| <3 | 22 (53.7) | 15 (71.4) | 7 (35.0) | |
| 3–20 | 16 (39.0) | 6 (28.6) | 10 (50.0) | |
| >20 | 3 (7.3) | 0 | 3 (15.0) | |
| Tumor grade (%) | 0.027§ | |||
| G1 (low) | 22 (53.7) | 15 (71.4) | 7 (35.0) | |
| G2 (intermediate) | 16 (39.0) | 6 (28.6) | 10 (50.0) | |
| G3 (high) | 3 (7.3) | 0 | 3 (15.0) | |
| No. of harvested LN, mean±SD (range) | 19.39±12.04 (5–55) | 18.38±11.67 (5–53) | 20.45±12.63 (6–60) | 0.589† |
| No. of metastatic LN, mean±SD (range) | 0.90±1.39 (0–6) | 0 | 1.85±1.50 (1–6) | NA |
| Resection margin status, %‖ | NA | |||
| R0 | 41 (100) | 21 (100) | 20 (100) | |
| R1/R2 | 0 | 0 | 0 |
Data are presented as number (%) unless otherwise indicated.
LN, lymph node; NA, not applicable.
*p-value is calculated for comparing two groups, LN metastasis (–) versus LN metastasis (+) group; †Unpaired t-test; ‡Pearson chi-square test; §Fisher exact test; ‖R0: complete resection grossly and microscopically; R1: microscopic residual lesions; R2: gross residual tumors.