Chest Computed Tomography Screening in Colorectal Cancer Patients

Pulmonary metastasis in rectal cancer: a retrospective study of clinicopathological characteristics of 404 patients in Chinese cohort

OBJECTIVES

This study aim to investigate the incidence, timing and risk factors of metachronous pulmonary recurrence after curative resection in patients with rectal cancer.

DESIGN

A retrospective cohort study.

SETTING

This study was conducted at a tertiary referral cancer hospital.

PARTICIPANTS

A total of 404 patients with rectal cancer who underwent curative resection from 2007 to 2012 at Beijing Hospital were enrolled in this study.

INTERVENTIONS

The pattern of recurrence was observed and evaluated.

PRIMARY AND SECONDARY OUTCOME MEASURES

The incidence and timing of recurrences by site were calculated, and the risk factors of pulmonary recurrence were analysed.

RESULTS

The 5-year disease-free survival for the entire cohort was 77.0%. The most common site of recurrence was the lungs, with an incidence of 11.4%, followed by liver. Median interval from rectal surgery to diagnosis of pulmonary recurrence was much longer than that of hepatic recurrence (20 months vs 10 months, P=0.022). Tumour location, pathological tumor-node-metastasis (TNM) stage and positive circumferential resection margin were identified as independent risk factors for pulmonary recurrence. A predictive model based on the number of risk factors identified on multivariate analysis was developed, 5-year pulmonary recurrence-free survival for patients with 0, 1, 2 and 3 risk factors was 100%, 90.4%, 77.3% and 70.0%, respectively (P<0.001).

CONCLUSIONS

This study emphasised that the lung was the most common site of metachronous metastasis in patients with rectal cancer who underwent curative surgery. For patients with unfavourable risk profiles, a more intensive surveillance programme that could lead to the early detection of recurrence is strongly needed.

Pulmonary recurrence predominates after combined modality therapy for rectal cancer: an original retrospective study

OBJECTIVE

To characterize patterns of recurrence in locally advanced rectal cancer treated with combined modality therapy (CMT): neoadjuvant chemoradiation + total mesorectal excision + adjuvant chemotherapy.

METHODS

A total of 593 consecutive rectal cancer patients (1998 to 2007) with locally advanced (stage II/III) disease (noted on endorectal ultrasound or magnetic resonance imaging) who received CMT were analyzed for patterns of recurrence.

RESULTS

After median 44-month follow-up (interquartile range, 25 to 64 months), 119 patients (20%) recurred: 105 distant, 7 local, 7 local and distant, and 112 distant-only recurrence. Ninety-three (78%) had single-organ recurrence, and 26 (22%) had multiple-organ recurrence. The most common site of distant recurrence was lung (69% of all patients with distant relapse); 20% had liver recurrence. Fourteen patients (2.4%) recurred locally. Pulmonary metastases were most commonly identified by computed tomographic scan versus abnormal positron emission tomographic (PET) scan or carcinoembryonic antigen (CEA). Risk factors associated with pulmonary recurrence were the following: pathologic stage, tumor distance from anal verge, lymphovascular or perineural invasion. Five-year freedom from pulmonary recurrence for patients with 0, 1, 2, or 3 risk factors was 99%, 90%, 61%, and 42%, respectively. Thirty of 59 patents with pulmonary recurrence underwent lung metastasectomy; 3-year freedom from recurrence was 37%.

CONCLUSIONS

Unlike colon cancer, which most frequently recurs in the liver, locally advanced rectal cancer treated with CMT relapses most frequently in the lung. Pulmonary metastasis was associated with advanced pathologic stage, low-lying tumor, lymphovascular invasion, or perineural invasion. Confirmation of pulmonary metastasis usually requires serial imaging because metastases are often small when initially detected, well below the resolution of PET, and not necessarily associated with elevated CEA. Individualized risk-based surveillance strategies are recommended in this patient population.