title: Clinicopathological value of immunohistochemical detection of occult involvement in pT3N0 gastric cancer.
abstract: BACKGROUND: In cases of pT3 gastric cancer, even when standard histological staining reveals no evidence of metastases in the regional lymph nodes, patients still may die of postoperative recurrence of the tumor. An attempt was made in the present study to explain the unfavorable outcome of such patients by investigating the presence of occult cancer cells in lymph nodes by immunostaining of cytokeratin.METHODS: We examined 2310 lymph nodes that had been removed from 83 patients with stage II gastric cancer (pT3, N0, M0). Two consecutive sections of 4 &mgr;m thick were prepared for simultaneous staining with hematoxylin and eosin and immunostaining with the CAM 5.2 monoclonal antibody against cytokeratin, respectively.RESULTS: Evidence of occult involvement was found in 299 of 2310 (13%) lymph nodes and in 54 of 83 (65%) patients with pT3 gastric cancer. An analysis of survival demonstrated the limited 5-year survival of patients with occult involvement in their resected lymph nodes, as compared with that of patients without involvement ( P < 0.01). Moreover, the patients in whom group 2 lymph nodes had occult cancer cells had a significantly poorer prognosis than those in whom occult involvement was limited to group 1 lymph nodes ( P < 0.05).CONCLUSIONS: The accuracy of predictions of prognosis of patients with pT3 gastric cancer should be greatly enhanced if cytokeratin-specific immunostaining is performed in conjunction with routine histopathological examination of lymph nodes.
authors.affiliation: First Department of Surgery and First Department of.
authors.forename: Jianhui
authors.initials: J
authors.lastname: Cai
authors.forename: Masahide
authors.initials: M
authors.lastname: Ikeguchi
authors.forename: Michio
authors.initials: M
authors.lastname: Maeta
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Kaibara
authors.forename: Takashi
authors.initials: T
authors.lastname: Sakatani