Workup/Staging

Question 1

What is the Bx approach for small (<1 cm) vulvar lesions?

Answer 1

For small (<1 cm) vulvar lesions, excisional Bx with a 1-cm margin, including the skin, dermis, and connective tissue.

Question 2

What is the Bx approach for large (>1 cm) vulvar lesions?

Answer 2

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)

Question 3

What is the basic workup of vulvar cancer?

Answer 3

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.

Question 4

Summarize the FIGO staging for vulvar cancer.

Answer 4

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 (lower-third 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

Question 5

Summarize the AJCC 2017 staging for vulvar cancer.

Answer 5

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

Question 6

Which pts with vulvar cancer require inguinal LND?

Answer 6

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.

Question 7

Which pts can have sentinal lymph node biopsy (SLNB) for nodal evaluation?

Answer 7

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

(Te Grootenhuis NC et al., Gynecol Oncol 2016)

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)

Question 8

In which pts with vulvar cancer is a unilat (instead of bilat) LND sufficient for workup?

Answer 8

Pts with a well-lateralized primary (>2 cm from midline) may undergo a unilat LND only.

Question 9

Is the staging system for vulvar cancer surgical or clinical?

Answer 9

FIGO surgical staging is used for vulvar cancer.

Question 10

Do imaging results affect the FIGO stage in vulvar cancer?

Answer 10

No. Imaging results are not included in FIGO staging.