Growth rate of chemotherapy-naïve lung metastasis from colorectal cancer could be a predictor of early relapse after lung resection.
OBJECTIVE
The aim of this study was to elucidate a potential risk factor for early relapse after pulmonary metastasectomy of colorectal cancer and to propose an optimal treatment strategy for lung metastasis with an aggressive nature.


METHODS
Seventy patients who underwent pulmonary metastasectomy for diachronically measurable pulmonary lesions were retrospectively analyzed. We calculated the tumor doubling time (TDT) as the growth rate of lung metastasis and divided the study population into two groups: Rapid (TDT ≤ 100 days) and Slow (TDT > 100 days).


RESULTS
The patients consisted of 47 males and 23 females, with a mean age of 63 years. Forty-two patients had a relapse after pulmonary metastasectomy with a median follow-up duration of 24 months. There was a significant difference in relapse-free survival between the Rapid and Slow groups (p = 0.047). Using a multivariate analysis, no preoperative chemotherapy and a high level of serum carcinoembryonic antigen were proven to be significant risk factors for relapse after metastasectomy. Meanwhile, multivariate analyses among 37 patients without preoperative chemotherapy indicated that TDT was the sole significant factor for relapse-free survival. In addition, eight of nine patients with relapse within 12 months were placed into the Rapid group.


CONCLUSIONS
Although this was a preliminary study with a small number of patients, it suggested that lung metastases demonstrating a TDT of 100 days or less have a high risk of early relapse after metastasectomy.
Department of Thoracic Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8550, Japan. gucci@med.nagoya-u.ac.jp.
Koji
http://orcid.org/0000-0002-5986-9419
K
Kawaguchi
Division of Surgical Oncology, Department of Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8550, Japan.
Keisuke
K
Uehara
Department of Gastroenterological Surgery (Surgery II), Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8550, Japan.
Goro
G
Nakayama
Department of Thoracic Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8550, Japan.
Takayuki
T
Fukui
Department of Thoracic Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8550, Japan.
Koichi
K
Fukumoto
Department of Thoracic Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8550, Japan.
Shota
S
Nakamura
Department of Thoracic Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8550, Japan.
Kohei
K
Yokoi
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use; D002272:Carcinoembryonic Antigen / Q000097:blood; D015179:Colorectal Neoplasms / Q000097:blood / Q000473:pathology*; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000097:blood / Q000473:pathology / Q000556:secondary* / Q000628:therapy*; D008297:Male; D059146:Metastasectomy; D008875:Middle Aged; D011013:Pneumonectomy; D011237:Predictive Value of Tests; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors
D000970:Antineoplastic Agents; D002272:Carcinoembryonic Antigen
Colorectal cancer; Growth rate; Lung resection; Metastasectomy; Tumor doubling time