Department of Gastroenterological Surgery, Aichi Cancer Center Hospital, Nagoya, Japan.
Dig Surg. 2011;28(5-6):352-9. doi: 10.1159/000332825. Epub 2011 Oct 28.
BACKGROUND/AIMS: The biological behavior of rectal cancers that invade the muscularis propria (pT2) has not been well studied. We retrospectively studied the pattern of lymph node metastases in patients with T2 rectal cancer.
We enrolled 88 patients who had undergone curative resection of T2 colorectal cancer through mesorectal excision and lateral pelvic lymph node dissection; we microscopically estimated the maximum depth of muscularis propria invasion and classified the results into 3 groups representing distinct growth patterns.
In cases of pT2 colorectal carcinomas, lateral pelvic lymph node metastases depended on the degree of muscularis propria invasion, and the frequency of metastasis increased with the depth of muscularis propria invasion. Lateral pelvic lymph node metastases were not observed when the depth of muscularis propria invasion was less than half of the thickness of the inner circular layer.
These findings suggest that lateral pelvic lymph node metastasis of pT2 colorectal cancer depends on the depth of vertical invasion, which is analogous to the findings in pT1 and pT3 cancers. This information will be useful in select cases in which resection of the lateral pelvic lymph node is required for the treatment of rectal cancer invading the muscularis propria (pT2).
背景/目的：侵犯固有肌层（pT2）的直肠肿瘤的生物学行为尚未得到很好的研究。我们回顾性研究了 T2 期直肠肿瘤患者的淋巴结转移模式。
我们纳入了 88 例通过直肠系膜切除术和侧盆淋巴结清扫术根治性切除 T2 结直肠癌的患者；我们显微镜下评估固有肌层侵犯的最大深度，并将结果分为 3 组，代表不同的生长模式。
在 pT2 结直肠癌中，侧盆淋巴结转移取决于固有肌层侵犯的程度，随着固有肌层侵犯深度的增加，转移的频率也增加。当固有肌层侵犯深度小于内环层厚度的一半时，未观察到侧盆淋巴结转移。
这些发现表明，pT2 结直肠癌的侧盆淋巴结转移取决于垂直侵犯的深度，这与 pT1 和 pT3 癌症的发现类似。这些信息对于需要切除侧盆淋巴结治疗侵犯固有肌层（pT2）的直肠癌的特定病例将非常有用。
