Construction and validation of a prognostic nomogram for anal squamous cell carcinoma

Cancer Med. 2022 Jan;11(2):392-405. doi: 10.1002/cam4.4458. Epub 2021 Dec 1.

Abstract

Background: Anal squamous cell carcinoma (ASCC) is the main subtype of anal cancer and has great heterogeneity in prognosis. We aimed to construct a nomogram for predicting their 1-, 3-, and 5-year overall survival (OS) rates.

Methods: Patients with ASCC, enrolled between January 1, 2010 and December 31, 2017, were identified from the SEER database. They were divided into a training group and a validation group in a ratio of 7:3. Univariate and multivariate Cox analyses were used to identify the prognostic factors for OS. Then a prognostic nomogram was established and validated by Harrell consistency index (C-index), area under the curve (AUC) of the receiver operating characteristic (ROC) curves, calibration plots, and decision curve analysis (DCA).

Results: We identified 761 patients in training group and 326 patients in validation group. Four prognostic factors including age, sex, AJCC stage, and radiotherapy were identified and integrated to construct a prognostic nomogram. The C-index and AUC values proved the model's effectiveness and calibration plots manifested its excellent discrimination. Furthermore, in comparison to the AJCC stage, the C-index, AUC, and DCA proved the nomogram to be of good predictive value. Finally, we constructed a risk stratification model for dividing patients into low-risk, medium-risk, and high-risk groups, and there were obvious differences in OS.

Conclusions: A prognostic nomogram was firstly established for predicting the survival probability of ASCC patients and helping clinicians improve their risk management.

Keywords: SEER; anus squamous cell carcinoma; nomogram; prognosis; risk stratification.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Anus Neoplasms / mortality*
  • Anus Neoplasms / pathology
  • Anus Neoplasms / therapy
  • Area Under Curve
  • Carcinoma, Squamous Cell / mortality*
  • Carcinoma, Squamous Cell / pathology
  • Carcinoma, Squamous Cell / therapy
  • Female
  • Humans
  • Male
  • Middle Aged
  • Neoplasm Staging
  • Nomograms*
  • Proportional Hazards Models
  • ROC Curve
  • SEER Program
  • Survival Rate