Assessing the impact of FDG-PET in the management of anal cancer.
OBJECTIVE
To assess the utility of FDG-PET in anal cancer for staging and impact on radiotherapy planning (RTP), response and detection of recurrent disease.


METHODS
Fifty histopathological anal cancer patients were reviewed between 1996 and 2006. The median age was 58 years (range 36-85) with 19 males:31females. Clinical assessment with CT was compared to PET. Impact on management, disease response, recurrence and metastases was evaluated.


RESULTS
The non-PET staging was Stage I(8), Stage II(18), Stage III(22), and Stage IV(2)s. The primary was strongly FDG avid in 98% with non-excised tumors compared to CT (58%). PET upstaged 17% with unsuspected pelvic/inguinal nodal disease. Pre-treatment PET identified 11 additional by involved nodal groups in 48 patients causing RTP amendments in 19%. Post-treatment PETs at median 17 weeks (range 9-28) showed complete responses in 20 (80%) and 5 (20%) partial responses (PR). PRs were biopsy positive in 2 and negative in 3. Fifteen had follow-up scans of which all nine PETs detected recurrences were pathologically confirmed.


CONCLUSIONS
Anal cancer is FDG-PET avid. PET upstages 17% and changes the RTP in 19%. PET can aid in anal cancer staging and identification of residual disease, recurrent/metastatic disease but warrants further prospective studies.
Nguyen
Brandon T
BT
Radiation Oncology Centre, Austin Health, Vic., Australia.
Joon
Daryl Lim
DL
Khoo
Vincent
V
Quong
George
G
Chao
Michael
M
Wada
Morikatsu
M
Joon
Michael Lim
ML
See
Andrew
A
Feigen
Malcolm
M
Rykers
Kym
K
Kai
Cynleen
C
Zupan
Eddy
E
Scott
Andrew
A
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001005:Anus Neoplasms / Q000000981:diagnostic imaging* / Q000532:radiotherapy; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging* / Q000532:radiotherapy / Q000556:secondary; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18