(P099) A Multidisciplinary Approach to the Management of Patients Diagnosed With Stage IV Anal Canal Cancer: A Multi-institutional Retrospective Study

Lorraine Portelance, MD, Neil Kopek, MD, Peter Hosein, MD, Maria Restrepo, MD, Caio Rocha-Lima, MD, Joe Levi, MD, Omar Mahmoud, MD, Adrian Ishkanian, MD, Govindarajan Narayanan, MD, Ike Akuniyli, MD; Sylvester Comprehensive Cancer Center, University of Miami; McGill University Health Center

Background: While there is a large amount of literature published on the management of patients with stage IV colorectal cancer presenting with liver-predominant metastatic disease, there is a paucity of data on the management of patients with stage IV squamous cell carcinoma (SCC) of the anal canal who have the same pattern of presentation. This retrospective study presents the results of a multidisciplinary approach adopted in two cancer centers where patients diagnosed with stage IV SCC of the anal canal (liver-predominant disease) and a good performance status (Eastern Cooperative Oncology Group [ECOG] 0–2) were offered a full course of concomitant chemoradiation followed by cisplatin-based palliative chemotherapy. In addition, for the patients who achieved a complete local response in the pelvis, consideration was given to proceed with local treatment of the liver metastasis (either by surgery or radioablation).

Methods: An institutional review board (IRB)-approved anal cancer databank including two institutions was queried to identify patients who presented with liver-predominant metastasis at diagnosis. A detailed retrospective review of the medical records was performed to capture demographic and clinical characteristics, as well as treatment delivery, response, toxicity, and survival.

Results: Between May 2009 and September 2013, a total of 11 patients were diagnosed with SCC of the anal canal and had liver-predominant metastatic disease at presentation. The median age was 53 years, and three patients were HIV-positive. The median follow-up was 23.6 months (range: 2–53 mo). Ten patients completed the full course of chemoradiation therapy with the Nigro protocol (mitomycin/fluorouracil and 54 Gy of external beam radiotherapy). Patients went on to receive systemic chemotherapy with cisplatin/fluorouracil. This was then followed by resection of residual liver metastases in seven patients and transarterial radioembolization with yttrium-90 microspheres in one patient. The 2-year overall survival (OS) and disease-free survival (DFS) rates were 87% and 27%, respectively. Complete response of the primary pelvic disease was documented during follow-up in 70% of the patients. These results were achieved with acceptable treatment-related toxicity. The most frequent acute toxicity encountered was reversible myelosuppression and radiation enteritis. No deaths were directly related to therapy.

Conclusion: Patients with anal canal SCC usually have significant pelvic symptoms at diagnosis from their primary disease. In our series, patients with liver-predominant stage IV disease had a high 2-year survival rate. Our experience suggests that upfront concomitant chemoradiation plays a significant role in controlling the pelvic symptoms in this population. Moreover, when an aggressive treatment approach was used, 27% was disease-free at 2 years, suggesting that the approach to patients with oligometastatic disease used in colorectal cancer may also be of benefit in patients with anal canal SCC.