Management of Stage I Squamous Cell Carcinoma of the Anal Canal

Abstract

IMPORTANCE The incidence of squamous cell carcinoma of the anal canal (SCCAC) is increasing. Although standard management of SCCAC includes the use of concurrent chemotherapy and radiotherapy (chemoradiotherapy), data are lacking on potentially less morbid, alternative management strategies, such as local excision, among patients with node-negative T1 disease. OBJECTIVES To examine the use of local excision among patients with T1 SCCAC and to compare overall survival relative to those who received standard treatment with chemoradiotherapy. DESIGN, SETTING, AND PARTICIPANTS This retrospective cohort study assessed 2243 patients in the National Cancer Database (2004-2012) between 18 and 80 years of age with T1N0M0 SCCAC. The association between the type of treatment received and overall risk of death was evaluated using multivariable Cox proportional hazards regression models. Data analysis was performed from June 29, 2016, to April 17, 2017. MAIN OUTCOMES AND MEASURES Overall survival. RESULTS Among 2243 patients with T1N0 SCCAC, 503 (22.4%) were treated with local excision alone (mean [SD] age, 54.5 [12.1] years; 240 [47.7%] male; 419 [83.3%] white) and 1740 with chemoradiotherapy (mean [SD] age, 57.0 [10.6] years; 562 [32.3%] male; 1547 [88.9%] white). Among those treated with chemoradiotherapy, 12 patients underwent a subsequent abdominoperineal resection. There was a statistically significant increase in the use of local excision during the study period (34 [17.3%] in 2004 to 68 [30.8%] in 2012; trend test, P < .001). This increase in use was observed among patients with primary tumors that measured 1 cm or smaller and greater than 1 cm to 2 cm or smaller (trend test, P < .001 for both). Overall survival at 5 years was not significantly different for the 2 management strategies (85.3% in the local excision cohort and 86.8% in the chemoradiotherapy cohort; log-rank test, P = .93). Overall risk of death was not significantly different for local excision alone relative to that for treatment with chemoradiotherapy (hazard ratio, 1.06; 95% CI, 0.78-1.44). These findings were robust when stratified by tumor size and when patients who underwent abdominoperineal resection after chemoradiotherapy were excluded. CONCLUSIONS AND RELEVANCE The use of local excision alone for the management of T1N0 SCCAC has significantly increased over time, with no clear decrement in overall survival. Because local excision may represent a lower-cost, less morbid treatment option for select patients with SCCAC, future studies are needed to better delineate its role and efficacy relative to the current standard of chemoradiotherapy.

Primary surgery with or without postoperative radiotherapy in early stage squamous cell carcinoma in the anal canal and anal margin

“…High locoregional failure rates were also reported by Goldman et al [10], in four out of seven (57%) patients treated with APR alone and in seven of nine (78%) patients treated with local excision alone for a stage T1-2N0 cancer in the anal canal. In a more recent study [14] based on the National Cancer Database, 2243 patients with stage T1N0 SCCA localized in the anal canal were analyzed. Five hundred and thirteen patients were treated with local excision alone and the remaining 1740 patients received CRT.…”

Evolving Concepts toward Individualized Treatment of Squamous Cell Carcinoma of the Anus

“…If located in the anal canal, LE carries a risk of sphincter damage and is therefore relatively contraindicated. Nevertheless, a recent retrospective cohort study of the US National Cancer Database on 2243 cases with T1 N0 SCCA has shown that over the period 2004-2012 LE was increasingly used in the more recent years, also for tumors of the anal canal [73]. Although criticized for its lack of information on the exact tumor location, LRC and DFS [74,75], this study and the Australian survey [71] illustrate that clinicians are reluctant to treat these small tumors with standard CRT.…”

High-Resolution Anoscopy Surveillance After Anal Squamous Cell Carcinoma: High-Grade Squamous Intraepithelial Lesion Detection and Treatment May Influence Local Recurrence

“…Excision alone of small anal/perianal cancers has had variable success, 19 , 20 , 22 , 23 but the use of EO is rising. 5 A population study of EO vs CRT showed reduced survival for EO after 80 months, despite the early stage; however, LR was not measured. 22 …”

“… 1 Serendipitous excision of anal canal (AC) T1 ASCC can occur with some evidence of noninferior outcomes to CRT. 5 Nonetheless, EO remains controversial 6 and a prospective UK study is underway. 7 Patients with inadequate excision margins and those with greater than stage T1N0 disease are treated with adjuvant CRT.…”