ABSTRACT
After receiving radical resection of primary rectal cancer,about 4％ to 30％ patients would occur local recurrence.Diagnosis of local recurrence relies on postoperative follow-up,physical examination,tumor markers and imageological examination.For the local recurrent patients,conservative therapeutic regimen had been popular in the past days with poor prognosis and quality of life.Nowadays multimodality treatment with radical resurgery combined with chemoradiotherapy and IORT has been taking the main part in the management of local recurrence.The choice of surgery depends on the site of recurrence and invasion situation inside the pelvic cavity.The aim of the radical reoperation is R0 resection because it leads to an optimistic prognosis.Previously irradiated patients are relatively safe after receiving median-dose reirradiation.For the cases whose recurrence are unavailable for radical resection,palliative operation and chemoradiotherapy may be the wise choice to relieve their symptoms and improve the quality of life.
ABSTRACT
The PIK3CA gene codes p100α,the catalytic subunit of phosphatidylinositol 3-kinase (PI3K) and is involved in the initiating the PI3K/AKT pathway.PIK3CA plays its biological roles through.downstream PI3K pathway. PIK3CA gene mutants can be detected in many kinds of tumors. The mutant PIK3CA gene can abnormally activate PI3K pathway,leading to the abnormal cell cycle,decreased cell adhesion,down regulated apoptosis and neovascularization,and then promotes tumor genesis and development.Recent researches have found that mutant PIK3CA gene is closely correlated with the genesis,development,differentiation,metastasis and drug resistance of colorectal cancer.Research of PIK3CA in colorectal cancer may provide significant evidence for the early diagnosis,gene screen,therapeutic regimen making,recurrence and follow up.