You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is Carcinoma cervix involving upper 2/3 of vagina without parametrial involvement are classed as: and explain in detail?
Involvement of the upper two thirds of the vagina, without parametrial involvement is stage IIA. With parametrial involvement is stage IIB. For some IIA radical hysterectomy may be considered and for IIB, chemoradiation is preferred. International Federation of Gynecology and Obstetrics Cervical Cancer Staging: Stage 0 Carcinoma-in-situ Stage I Confined to the cervix Stage IA1: Minimal invasion Stage IA2: Stage IB1: More than A2 and Stage IB2: >4 cm total diameter Stage II Involvement of the upper two thirds of the vagina, without parametrial involvement (A) or with parametrial involvement (B) Stage III A. Involvement of the lower third of the vagina B. Involvement of a parametria to the sidewall or obstruction of one or both ureters on imaging Stage IV A. Local involvement of the bladder or rectum B. Distant metastases Ref: Cain J., ElMasri W.M., Gregory T., Kohn E.C. (2010). Chapter 41. Gynecology. In F.C. Brunicardi, D.K. Andersen, T.R. Billiar, D.L. Dunn, J.G. Hunter, J.B. Matthews, R.E. Pollock (Eds), Schwaz's Principles of Surgery, 9e.