Background Brain derived neurotrophic factor (BDNF) is a neurotrophin involved in neural and metabolic diseases, but it is also one of the crucial factors in cancer development and metastases. In the current study, we investigated serum BDNF concentrations in patients that underwent surgical treatment for colorectal cancer or pancreatic cancer. Methods Serum BDNF concentrations were measured with standard enzyme-linked immunosorbent assays, before and on the third day after the operation, in 50 consecutive patients with colorectal cancer and 25 patients with pancreatic cancer (tumours in the head of pancreas). We compared pre- and postoperative BDNF levels, according to the subsequent TNM stage, histologic stage, lymph node involvement, neuro- or angio-invasion, and resection range. Results In the pancreatic cancer group, BDNF concentrations fell significantly postoperatively (p = 0.011). In patients that underwent resections, BDNF concentrations fell (p = 0.0098), but not in patients that did not undergo resections (i.e., laparotomy alone). There were significant pre- and postoperative differences in BDNF levels among patients with (p = 0.021) and without (p = 0.034) distant metastases. Significant reductions in BDNF were observed postoperatively in patients with small tumours (i.e., below the median size; p = 0.023), in patients with negative angio- or lymphatic invasion (p = 0.028, p = 0.011, respectively), and in patients with lymph node ratios above 0.17 (p = 0.043). In the colon cancer group, the serum BDNF concentrations significantly fell postoperatively in the entire group (p = 0.0076) and in subgroups of patients with or without resections (p = 0.034, p = 0.0179, respectively). Significant before-after differences were found in subgroups with angioinvasions (p = 0.050) and in those without neuroinvasions (p = 0.049). Considering the TNM stages, the postoperative BDNF concentration fell in groups with (p = 0.0218) and without (p = 0.034) distant metastases and in patients with tumours below the median size (p = 0.018). Conclusion Our results suggested that BDNF might play an important role in gastrointestinal cancer development. BDNF levels were correlated with tumour volume, and with neuro-, angio- and lymphatic invasions. In pancreatic cancer, BDNF concentrations varied according to the surgical procedure and they fell significantly after tumour resections. Thus, BDNF may serve as a potential marker of complete resections in underdiagnosed patients. However, this hypothesis requires further investigation. In contrast, no differences according to the procedure was made in patients with colon cancer.

中文翻译：

---

胃肠癌完全根治性切除后脑源性神经营养因子下降

背景脑源性神经营养因子（BDNF）是一种参与神经和代谢疾病的神经营养因子，但它也是癌症发展和转移的关键因素之一。在目前的研究中，我们调查了接受结直肠癌或胰腺癌手术治疗的患者的血清 BDNF 浓度。方法 采用标准酶联免疫吸附试验，在连续 50 例结直肠癌患者和 25 例胰腺癌（胰头肿瘤）患者术前和术后第 3 天测定血清 BDNF 浓度。我们根据随后的 TNM 分期、组织学分期、淋巴结受累、神经或血管浸润以及切除范围比较了术前和术后 BDNF 水平。结果 在胰腺癌组中，BDNF 浓度在术后显着下降（p = 0.011）。在接受切除术的患者中，BDNF 浓度下降（p = 0.0098），但在未接受切除术（即仅剖腹手术）的患者中没有。有 (p = 0.021) 和没有 (p = 0.034) 远处转移的患者的 BDNF 水平在术前和术后存在显着差异。在小肿瘤患者（即低于中位大小；p = 0.023）、血管或淋巴浸润阴性的患者（分别为 p = 0.028、p = 0.011）和淋巴结比率高于 0.17 (p = 0.043)。在结肠癌组中，整个组（p = 0.0076）和有或没有切除的患者亚组（p = 0.034，p = 0.0179，分别）。在有血管浸润的亚组（p = 0.050）和没有神经浸润的亚组（p = 0.049）中发现了显着的前后差异。考虑到 TNM 分期，术后 BDNF 浓度在有 (p = 0.0218) 和没有 (p = 0.034) 远处转移的组以及肿瘤大小低于中位数的患者 (p = 0.018) 中下降。结论 我们的研究结果表明，BDNF 可能在胃肠道癌症的发展中起重要作用。BDNF 水平与肿瘤体积、神经、血管和淋巴侵袭相关。在胰腺癌中，BDNF 浓度因手术程序而异，并且在肿瘤切除后显着下降。因此，BDNF 可作为诊断不足患者完全切除的潜在标志物。然而，这一假设需要进一步研究。相比之下，结肠癌患者的手术过程没有差异。