Vulvar Flashcards
Appx how many pts are affected by vulvar cancer per yr in the United States? What is the incidence of vulvar cancer in the United States?
∼6,020 pts are estimated to be affected in 2017 by vulvar cancer in the United States. The incidence is 2.5/100,000 people.
Vulvar cancer accounts for what % of gyn malignancies? What % of all malignancies in women are vulvar malignancies?
Vulvar cancer represents 3%–5% of all gyn malignancies. This comprises 1%–2% of all cancers in women.
What are the risk factors for vulvar cancer?
Risk factors for vulvar cancer:
- Increasing age
- HPV
- Vulvar intraepithelial neoplasia (VIN)
- Bowen Dz (squamous cell CIS)
- Paget Dz (lesions arising from Bartholin gland, urethra, or rectum)
- Smoking
- Immune deficiency
- Lichen sclerosis
What HPV subtypes are associated with vulvar cancer?
HPV subtypes associated with vulvar cancer include 6, 16, 18, and 33.
What is the function of HPV-associated oncoproteins?
It is thought that HPV-associated oncoproteins bind and inactivate tumor suppressor proteins such as Rb, p53, and p21.
What are the subsites of the vulva?
- Ant and post fourchette
- Clitoris (clitoral hood and gland)
- Labia minora and majora
- Mons pubis
- Perineal body
- Urethral meatus
- Vaginal orifice
If a malignancy with the epicenter in the vagina involves the vulva, what is the primary?
Vulvar primary. Considering primary vaginal cancers are rare, any tumor within the vagina touching the vulva should be considered a vulvar primary.
What histology constitutes the vast majority of vulvar cancers? Name other histologies of tumors found on the vulva.
The most common vulvar histology is squamous cell carcinoma (80%– 90%). Verrucous is a less aggressive subtype of vulvar SCC with rare LN spread.
2. Other histologies include melanoma, basal cell, Merkel cell, sarcoma, and adenocarcinomas of the Bartholin glands.
What are the most common presenting Sx of pts with vulvar cancer?
Common presenting Sx of vulvar cancer: pruritus, vulvar discomfort or pain, dysuria, oozing, or bleeding.
In which subsites does vulvar cancer most commonly arise?
70% of vulvar cancers arise from the labia majora/minora.
How is “locally advanced” vulvar cancer defined?
Locally advanced vulvar cancer is defined as T2 tumors >4 cm or extension into anus and/or vagina, or T3. Also defined as any burden that cannot be resected without exenterative Sg.
What are the 1st-, 2nd-, and 3rd-echelon LN regions in vulvar cancer, and which subsite is associated with skip nodal mets?
LN regions in vulvar cancer:
1st echelon: superficial inguinofemoral
2nd echelon: deep inguinofemoral and femoral
3rd echelon: external iliac nodes
The clitoris can drain directly to the deep inguinofemoral or pelvic nodes. What is the strongest predictor of LN involvement in vulvar cancer?
The strongest predictor of LN involvement in vulvar cancer is DOI.
Estimate the risk of inguinal LN involvement based on the DOI of a vulvar tumor: <1 mm, 1–3 mm, 3–5 mm, and >5 mm
LN involvement by cervical tumor DOI: ≤1 mm: <5% 1–3 mm: 8% 3–5 mm: 27% 5 mm: 34%
What is the rate of pathologic inguinal positivity for cN0 pts?
25%-30%
Van Der Zee et al., GROINSS-V 2008
If someone is found to have a positive inguinal LN, what is the rate of positive pelvic LNs and contralat inguinal LNs?
Pelvic LN+: 30%
Contralat inguinal LN+: 25%–30%
(Homesley HD et al., Obstet Gynecol 1986)
What is the Bx approach for small (<1 cm) vulvar lesions?
For small (<1 cm) vulvar lesions, excisional Bx with a 1-cm margin, including the skin, dermis, and connective tissue.
What is the Bx approach for large (>1 cm) vulvar lesions?
For large (>1 cm) vulvar lesions, wedge Bx including surrounding skin. These should be taken from the edge of the lesion to include the interface b/t normal skin and the tumor to determine whether there is invasion of adjacent epithelium. (Baldwin P et al., Curr Obst Gyn 2005)
What is the basic workup of vulvar cancer?
Vulvar cancer workup:
- H&P (includes inguinal LN assessment, DRE)
- EUA if adequate assessment cannot be done due to pain while awake, routine PAP smear of cervix, and colposcopy of the vagina and rest of vulva. Other investigations such as cysto or proctoscopy only if clinically indicated (e.g., involvement of urethra or anus)
- Labs: CBC (to check for anemia); UA (to r/o infection), HIV testing (to r/o immunodeficiency when clinically indicated), BMP, LFTs
- Imaging: PET/CT C/A/P with IV contrast. Pelvic MRI to assist in delineating primary and Tx planning.
Summarize the FIGO staging for vulvar cancer.
FIGO IA: lesion ≤2 cm, confined to vulva and/or perineum with stromal invasion ≤1 mm, N0
FIGO IB: lesion >2 cm, confined to vulva and/or perineum with stromal invasion >1 mm, N0
FIGO II: lesion of any size with extension to adjacent structures (lowerthird of urethra, lower-third of vagina, or anus), N0
FIGO III: positive inguinofemoral LN
FIGO IIIA: 1–2 LNs each <5 mm
FIGO IIIB: ≥3 LNs each <5 mm or ≥2 LNs = 5 mm
FIGO IIIC: node(s) with extracapsular spread
FIGO IVA: extension into bladder or rectal mucosa (not muscle/wall), pelvic bone fixation, extension into upper 2/3 of urethra or vagina, or fixed or ulcerated regional LN mets
FIGO IVB: DMs, including pelvic LN
Summarize the AJCC 2017 staging for vulvar cancer.
T1a = FIGO IA T1b = FIGO IB T2 = FIGO II T3 = FIGO IVA N0 = No inguinofemoral LN(s) N0(i+) = ITC† in the inguinofemoral regions, ≤0.2 mm N1a* = 1–2 LNs <5 mm N1b = 1 LN ≥5 mm N2a* = ≥3 LNs each <5 mm N2b = ≥2 LNs ≥5 mm N2c = regional LN(s) with extracapsular spread N3 = fixed or ulcerated regional LN †Isolated tumor cells *Includes micromets *When recording LN results, include size, location, and laterality
Which pts with vulvar cancer require inguinal LND?
In vulvar cancer, all pts with clinically suspicious nodes require bilat inguinal LND unless there are bulky unresectable nodes. For pts with no clinically suspicious nodes, the need for nodal evaluation depends primarily on DOI. If the DOI is <1 mm, a nodal evaluation may not be needed unless there is LVSI or high grade.
Which pts can have sentinal lymph node biopsy (SLNB) for nodal evaluation?
Pt with low-risk Dz: cN0, unifocal T1–2 (<4 cm) with DOI >1 mm. The GROINSS-V (Groningen International Study on Sentinel Nodes in Vulvar Cancer) study evaluated safety of SLNB in early stage vulvar cancer. 403 pts
with T1/T2 (<4 cm) SCC with DOI >1 mm and cN0 underwent SLNB. If SLNB was negative→ observation. If SLNB positive→ inguinofemoral LND. RT was recommended if ECE or ≥2 LN+ (10% of the SLN+ received). Initial results showed SLN– pts (69%) had an isolated groin recurrence of 2.5%. Morbidity was low in the SLNB-only arm. (Van der Zee et al., JCO 2008)
Updated Results showed the following:
SLNB–: 5-yr LR = 25%; 10-yr LR = 36%; isolated groin recurrence = 2.5%
SLNB+: 5-yr LR = 33%; 10-yr LR = 46%; isolated groin recurrence = 8% 10-yr DSS: SLNB– 91% vs. SLNB+ 65%; if LR: 70% (all comers), SLNB– 81%, SLNB+ 45%
10-yr OS: SLNB– 69% vs. SLNB+ 44%
Size of SLNB from the GROINNS-V was important
DFS decreased with SLNB mets >2 mm (95% → 70%)
Rate of Non-SLNB LN positivity: ITC* = 4%, ≤2 mm = 11%, 2–5 mm = 13%, >5 mm = 48%
*ITC = individual tumor cells
The Gynecologic Oncology Group’s GOG 173 study assessed sensitivity of SLNB. 452 women with SCC limited to vulvar 2–6 cm and DOI ≥1 mm underwent lymphatic mapping, SLNB, and then LND. Only 11 pts with a +LN on dissection were negative on SLNB. Sensitivity of SLNB was 92%. In tumors <4 cm, the FN rate was 2%. (Levenback CF et al., JCO 2012)
In which pts with vulvar cancer is a unilat (instead of bilat) LND sufficient for workup?
Pts with a well-lateralized primary (>2 cm from midline) may undergo a unilat LND only.