Workup/Staging

Question 1

What are 4 common presenting Sx in anal cancer?

Answer 1

Bleeding, pain/sensation of mass, rectal urgency, and pruritus

Question 2

What does the workup for anal cancer pts include?

Answer 2

Anal cancer workup: H&P (including gyn exam for women with Cx cancer screening), labs (HIV if risk factors), imaging, Bx of lesion, and FNA of suspicious LN

Question 3

What imaging studies are typically done for anal cancer pts?

Answer 3

Chest/abdominal CT + pelvic CT or MRI with IV contrast. Consider PET/CT in same position as simulation for staging & planning guidance. (NCCN Guidelines 2018)

Question 4

Is PET/CT more or less sensitive than diagnostic CT alone for detecting locoregional and met Dz?

Answer 4

Mistrangelo M et al. (IJROBP 2012) found PET/CT to be sup to CT in detecting the primary tumor (89% vs. 75%); Bhuva NJ et al. also found PET/CT diagnosed occult metastatic Dz following CT imaging in 5% of pts and changed staging in 42% of pts, with the majority being upstaged. (Ann Oncol 2012)

Question 5

What features of anal lesions need to be appreciated on physical exam? Why?

Answer 5

The degree of circumferential involvement and anal sphincter tone should be appreciated, b/c these may dictate Tx.

Question 6

What is the approach to suspicious inguinal LNs in anal cancer pts?

Answer 6

FNA Bx should be considered for suspicious inguinal LNs.

Question 7

On what is the T staging for anal cancer based? Define T1–T4.

Answer 7

T staging as per AJCC 8th edition for anal cancer is based on tumor size & invasion of adjacent organs.

TX: Primary tumor not assessed

T0: No evidence of primary tumor

Tis: High-grade squamous intraepithelial lesion

T1: ≤2 cm

T2: >2 but ≤5 cm

T3: >5 cm

T4: Invasion of adjacent organs (vagina, urethra, and bladder)

Question 8

Does tumor invasion of sphincter muscle by anal cancer constitute a T4 lesion?

Answer 8

No. Direct invasion of the rectal wall, perirectal skin, SQ tissue, or sphincter muscle are not classified as T4.

Question 9

Most pts with anal cancer present with what T stage?

Answer 9

Most anal cancer pts present at stage T2 or T3.

Question 10

What is the N staging for mets in inguinal, mesorectal, or internal iliac LNs?

Answer 10

Mets to inguinal, mesorectal, or internal iliac LNs is staged as N1a.

Question 11

What is the N staging for mets in external iliac LNs?

Answer 11

Mets to external iliac LNs is staged as N1b.

Question 12

What is the N staging for mets in external iliac LNs with concurrent mets in N1a nodes?

Answer 12

Mets to external iliac LNs with concurrent mets in N1a nodes is N1c.

Question 13

Is mets to common iliac nodes considered M1 Dz?

Answer 13

Yes. Mets to common iliac LNs is considered M1 Dz.

Question 14

What is the AJCC 8th edition (2017) stage grouping for anal cancer?

Answer 14

Stage I: T1N0

Stage IIA: T2N0

Stage IIB: T3N0

Stage IIIA: T1–2N1

Stage IIIB: T4N0

Stage IIIC: T3N1 or T4N1

Stage IV: Any T Any N M1

Question 15

What are the 5-yr OS and DFS rates after surgical resection alone for anal cancer?

Answer 15

The 5-yr OS rate after complete surgical resection (APR) is ∼70%, and the DFS rate is ∼40%. (Mayo review of 118 pts: Boman BM et al., Cancer 1984)

Question 16

What % of pts who relapse develop local recurrent Dz as part of the total failure pattern?

Answer 16

∼80% develop local recurrent Dz. (Boman BM et al., Cancer 1984. Note: This was also a surgical series.)

Question 17

What are the OS and sphincter preservation rates for all-comers with anal cancer at 8 yrs after definitive CRT?

Answer 17

OS is ∼70% (RTOG 9811 & 0529) and sphincter preservation rate is ∼65% after CRT alone.