In a post hoc analysis of the phase III IDEA France trial reported in the Journal of Clinical Oncology, Delattre et al found that the presence of tumor deposits was associated with poorer prognosis in patients with stage III colon cancer receiving 3 or 6 months of adjuvant FOLFOX (fluorouracil, leucovorin, and oxaliplatin) or CAPOX (capecitabine and oxaliplatin).

Study Details

The analysis included 1,942 patients classified according to the 7th edition of the American Joint Committee on Cancer (AJCC) TNM staging system. In the 7th edition staging system, tumor deposits are considered a separate entity (new pN1c category) from lymph node metastases, with the presence or number of deposits not considered in pN staging in cases of concomitant lymph node metastases. Some data have suggested that the addition of tumor deposits to the lymph node metastasis count may improve the assessment of prognosis and aid in treatment decisions.

The primary outcome measure was disease-free survival among patients with vs without tumor deposits.

Tumor Deposits and Prognosis

Among the 1,942 patients included in the analysis, 184 (9.5%) had tumor deposits. A total of 1,454 patients (74.9%) were staged as pN1. Patients in the pN1a/b and pN1c subgroups had similar disease-free survival (P = .7672). The 3-year disease-free survival rates in patents staged as pN1a/b, pN1c, and pN2 were 78.8%, 80.7%, and 58.9%, respectively.

The 3-year disease-free survival rates were 65.6% among tumor deposit–positive patients vs 74.7% among tumor deposit–negative patients (P = .0079). The presence of tumor deposits was associated with poorer prognosis across all pN stages; 3-year disease-free survival was 66.2% vs 79.5% among pN1a/b patients with vs without tumor deposits (P = .0067) and 50.2% vs 60.0% among pN2 patients with vs without tumor deposits (P = .1642).

On multivariate analysis, the presence of tumor deposits was associated with higher risk of recurrence or death (hazard ratio [HR] = 1.36, P = .0201). Other factors associated with poor prognosis were pT4 or pN2 disease (HR = 2.21, P < .001), a 3-month course vs 6-month course of adjuvant treatment (HR = 1.29, P = .0029), tumor obstruction (HR = 1.28, P = .0233), and male sex (HR = 1.24, P = .0151).

The investigators concluded, “The presence of [tumor deposits] is an independent prognostic factor for [disease-free survival] in patients with stage III [colon cancer]. The addition of [tumor deposits] to lymph node metastases may help to better define the duration of adjuvant therapy.”

Magali Svrcek, MD, PhD, of Hospital Saint-Antoine, is the corresponding author for the Journal of Clinical Oncology article.

Disclosure: The study was supported by the French National Institute of Cancer, French Ministry of Health by Program Hospitalier de Recherche Clinique 2009, and Groupe Coopérateur Multidisciplinaire en Oncologie. For full disclosures of the study authors, visit ascopubs.org.