Cervical cancer

Epidemiology
11,000 cases per year in US; 3500 deaths
60,000 cases of cervical carcinoma in situ

Risk factors
HPV16 - squamous cell
HPV18 - adenocarcinoma
HIV
DES exposure - clear cell cancers of cervix and vagina
Smoking
Higher rates in black women
More common in younger women

Pathology
80% squamous, 10% adeno, 5% mixed adeno/squamous
Rare histologies include small cell (high rate of node mets; associated with HPV18)
Pap smear abnormalities
1) ASCUS: test for HPV; if + go to colposcopy; if negative repeat pap in 6 to 12 months
2) LGSIL: colposcopy
3) HGSIL: LEEP/conization

Prognostic factors
Age
Race
Socioeconomic status
Anemia
Tumor size
Cell type does not matter

Therapy
Microscopic disease
IA1: local excision only or simple hysterecomy (no PLND)
IA2: radical hysterectomy (removes uterus, cervix, parametria, upper vagina and do PLND)
Medically inoperable: brachy alone to 70Gy for IA1; brachy + WPRT for IA2

Localized, non-bulky disease
Single modality treatment is OK
Radical hysterectomy, or,
WPRT + brachy (total tumor dose 80-85Gy)

Risk factors which buy you radiation after hysterectomy
Deep stromal invasion (deeper than 1/3), LVSI, tumor larger than 4cm
Rotman: randomized patients with any of these risk factors to postop RT (WPRT 46 - 50.4Gy) vs. observation.  RT had a significant PFS benefit (HR for progression 0.6) with a strong trend to improved OS (HR for death 0.7).

Risk factors which buy you chemo-radiation after hysterectomy
3 P's: positive margins, positive nodes, parametrial invasion
Peters: randomized women with any of these risk factors to postop RT (WPRT to 45Gy) vs. RT + concurrent cis/5-FU.
Chemotherapy had a significant OS benefit (81 vs 71% at 5 years) and PFS benefit (80 vs. 63% at 5 years) with increased acute toxicity (hematologic, GI)

Locally advanced/bulky disease
Therapy includes concurrent chemo/RT/brachy

Study		OS	PFS
RTOG 7920	WPRT	55%
	WPRT + PA RT	65%
RTOG 9001	WPRT+PA RT	43%	43%
	WPRT + Cis-5FU	73%	68%
GOG 123	RT then surgery	75%	68%
	CRT then surgery	85%	82%

Brachytherapy technique
Point A = 2cm superior and 2cm lateral to flange on tandem; represents uterine vessels
Point B = 2cm superior and 5cm lateral to flange on tandem; represents parametrium/pelvic sidewall
Bladder point = center of Foley balloon
Rectal point = 5mm posterior to the posterior edge of vaginal packing
Both bladder and rectal points should receive < 75Gy
You should be able to ID the sigmoid colon on a CT scan
A good implant:
 -Tandem bisects colpostats on lateral view (at midline on the AP)
 -Colpostats sit above the flange
 -Sufficient anterior and posterior packing to separate the bladder/rectum from the high dose areas
LDR to HDR conversion ratio: 1:0.54
Most common HDR fractionation is 6Gy x 5