M1A/M1B esophageal carcinoma: Clinical relevance

Objective: The 1997 staging system for esophageal carcinoma subdivides dist ant metastatic disease (M1) into M1a (nonregional lymph node metastases) an d M1b (other metastases). This study evaluates the relevance of this classi fication. Methods: One hundred forty patients were identified with M1 disea se, 36 (26%) M1a and 104 (74%) M1b, The histologic type was adenocarcinoma in 118 (84%), squamous cell in 18 (13%), and adenosquamous in 4 (3%), with a similar distribution for M1a and M1b (P = .3), Forty-five underwent surge ry 28 (78%) with M1a disease and 17 (16%) with with disease (P < .001). Che motherapy and/or radiation therapy was given to 33 (73%) surgical patients and 63 (66%) nonsurgical patients (P =,4), 28 (78%) with M1a disease and 68 (66%) with M1b disease (P =,17), Results: Mediad and 5-year survivals were 11 months and 6% in patients with M1a disease and 5 months and 2% in those with M1b disease (P = .001). Surgery provided no advantage in M1b (P = .6) or M1a disease (P = .2), Multivariable analysis demonstrated that patients with M1b disease had 1.8 times the mortality risk of those with M1a diseas e (CI 1.2-2.7, P = .004), and patients without chemotherapy and/or radiothe rapy had 2.2 times the mortality risk of those with chemotherapy and/or rad iotherapy (CI 1.5-3.2, P < .001). Despite the prevalence of surgery in pati ents with M1a disease, the analysis suggests that M1a and use of chemothera py and/or radiotherapy, rather than surgery, account for the small, clinica lly unimportant differences in survival, Conclusions:We conclude that (1) a lthough there are statistically significant survival differences between M1 a and M1b disease, these differences are not clinically important; (2) chem otherapy and/or radiotherapy is associated with a modest survival benefit; and (3) surgery offers no survival advantage.