FIGO Cancer Staging Systems

Very often students appearing for exams are asked about FIGO cancer staging of various gynecological malignancies. In this blog I want to put to pen my views on the same. What students need to know and are not always taught is why do we need to have a staging system in the first place? The primary objectives of any good staging system are:

• To help the clinician in planning treatment
• To provide indication of prognosis
• To assist the physician in evaluating the results of treatment
•  To facilitate the exchange of information between treatment centers (to correctly compare their success/failure rates)
• To provide an evidence-based approach to cancer

A good staging system must have 3 basic characteristics:

• It must be valid,
• It should be reliable, and
• Most importantly it should be practical

Historically the first staging system for gynecological cancers appeared around the turn of the 20^th century; it was applied to the carcinoma of the cervix- the most common cancer affecting women at that time. Professor J. Heyman (the Radiumhemmet, Stockholm, Sweden), Dr A. Lacassagne (Radium Institute of the University of Paris, France) and Professor F. Voltz (Munich, Germany), appointed by the Radiological Sub-Commission of the Cancer Commission of the Health Organization of the League of Nations, recommended a  staging classification designed to mimic the natural history of the disease, i.e., the different stages representing the progressive growth of the tumor. These recommendations – adopted by the Sub-Commission with minor modifications – were published in 1929 and became known as the League of Nations Classification for Cervical Cancer. To cut the long history short, this classification underwent many changes and ultimately after FIGO and the FIGO Committee on Gynecologic Oncology were officially formed, it became known as FIGO staging system.

I want to draw the students’ attention to the following facts about FIGO cancer staging system

• Although FIGO is an acronym for International Federation of Gynecology and Obstetrics it is written as FIGO based on the same phrase in French language: students get confused because they are unaware of this. Currently it has member societies in 125 countries or territories. The current president for the period 2012-2015 is Professor Sir Sabaratnam Arulkumaran from United Kingdom.
• Over the years, all staging systems for gynecological malignancies with the exception of cervical cancer and gestational trophoblastic neoplasia – have shifted from a clinical to a surgical–pathological basis.
• When asked students always mention the FIGO nomenclature Montreal, 1994 for carcinoma cervix and FIGO nomenclature, Rio de Janeiro, 1988 for carcinoma of endometrium. But they should be aware that things have changed: FIGO staging systems for cervix, endometrium, sarcomas, ovary and vulva have been revised for the first time in over a decade. Remember “change is the most constant thing in life” and FIGO staging is no exception.
• As regards carcinoma of endometrium, the FIGO staging system was revised in 2009; changes include the classification for disease stages I through III. In the revised staging system, pelvic cytology results are excluded from changing the disease stage and should be reported separately. In the 2009 FIGO staging system, stage I is divided into 2 categories, with stage IA denoting less than 50% myometrial invasion, and stage IB denoting greater than or equal to 50% myometrial invasion. Uterine serosal disease, which was formerly categorized as stage IC in previous FIGO staging systems, is now categorized as stage IIIA. Cases of endocervical glandular involvement are considered stage I. In addition, stage IIIC is further subdivided into stage IIIC1 (metastases to pelvic lymph nodes only); and stage IIIC2 (metastases to para-aortic lymph nodes). See table I.
• The new FIGO nomenclatures are shown in tables below.

Table I: FIGO staging of Carcinoma of the Cervix
IA1	Confined to the cervix, diagnosed only by microscopy with invasion of < 3 mm in depth and lateral spread < 7 mm
IA2	Confined to the cervix, diagnosed with microscopy with invasion of > 3 mm and < 5 mm with lateral spread < 7mm
IB1	Clinically visible lesion or greater than A2, < 4 cm in greatest dimension
IB2	Clinically visible lesion, > 4 cm in greatest dimension
IIA1	Involvement of the upper two-thirds of the vagina, without parametrial invasion, < 4 cm in greatest dimension
IIA2	> 4 cm in greatest dimension
IIB	With parametrial involvement
IIIA/B	Unchanged
IVA/B	Unchanged

Table II: FIGO staging of Carcinoma of the Endometrium
IA	Tumor confined to the uterus, no or < ½ myometrial invasion
IB	Tumor confined to the uterus, > ½ myometrial invasion
II	Cervical stromal invasion, but not beyond uterus
IIIA	Tumor invades serosa or adnexa
IIIB	Vaginal and/or parametrial involvement
IIIC1	Pelvic node involvement
IIIC2	Para-aortic involvement
IVA	Tumor invasion bladder and/or bowel mucosa
IVB	Distant metastases including abdominal metastases and/or inguinal lymph nodes

Table III: FIGO staging of Carcinoma of the Vulva
IA	Tumor confined to the vulva or perineum, ≤ 2cm in size with stromal invasion ≤ 1mm, negative nodes
IB	Tumor confined to the vulva or perineum, > 2cm in size or with stromal invasion > 1mm, negative nodes
II	Tumor of any size with adjacent spread (1/3 lower urethra, 1/3 lower vagina, anus), negative nodes
IIIA	Tumor of any size with positive inguino-femoral lymph nodes (i) 1 lymph node metastasis greater than or equal to 5 mm (ii) 1-2 lymph node metastasis(es) of less than 5 mm
IIIB	(i) 2 or more lymph nodes metastases greater than or equal to 5 mm (ii) 3 or more lymph nodes metastases less than 5 mm
IIIC	Positive node(s) with extracapsular spread
IVA	(i) Tumor invades other regional structures (2/3 upper urethra, 2/3 upper vagina), bladder mucosa, rectal mucosa, or fixed to pelvic bone (ii) Fixed or ulcerated inguino-femoral lymph nodes
IVB	Any distant metastasis including pelvic lymph nodes

I have not come across changes in FIGO nomenclature for cancer of ovary as yet; as soon as I do, I will post it.
Reference: Mutch DG: The New FIGO staging system for cancers of the vulva, cervix, endometrium, and sarcomas. Gynecol Oncol 115:325-328, 2009
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