Study Objective To revisit thoracic endometriosis cases in literature and compare symptoms, diagnosis, pathology, treatment and follow-up based on the catamenial or non-catamenial nature of the disease. Design A PubMed/MEDLINE search was conducted using the key words: diaphragm endometriosis, thoracic endometriosis, thoracic endometriosis syndrome, catamenial pneumothorax. Setting n/a Patients or Participants 480 cases of thoracic endometriosis were included in this review. 61 presented with non-catamenial symptoms and 419 had catamenial symptoms. Patients were compared based on the presence of chest pain, dyspnea, hemoptysis, pneumothorax history, pneumothorax type, use and types of imaging techniques, pre- and postoperative medication, type of surgery, presence of endometriosis in pathological evaluation, location of thoracic endometriosis, follow-up period and recurrence. Interventions Types of surgeries evaluated in this review were laparoscopy (LS), laparotomy (LT), video-assisted thoracoscopic surgery (VATS), thoracotomy. Measurements and Main Results A significantly higher number of patients presented with preoperative chest pain (79.7%), dyspnea (52.2%) and pneumothorax (78.9%) in the catamenial group (p <0.001). Pneumothorax occurred more frequently on the right side in both groups. 285 patients (68%) in the catamenial group received a positive imaging finding whereas this number was significantly less in the non-catamenial group (59%, p = 0.003). Majority of patients in both groups didn't receive any pre-/post-operative medication. VATS was the most common surgery in the catamenial group (56.6%). Whereas LT/LS was more frequently performed in the non-catamenial group (70.5%). Majority of the patients in both groups received a pathological finding of endometriosis Conclusion Catamenial and non-catamenial nature of the disease caused a significant difference in presenting symptoms, preoperative evaluation, surgical and medical treatment and recurrence. Although most of patients presented with catamenial disease, majority of the non-catamenial patients also received a positive pathological finding. Therefore, it is important to keep thoracic endometriosis in mind when dealing with patients with non-catamenial symptoms. To revisit thoracic endometriosis cases in literature and compare symptoms, diagnosis, pathology, treatment and follow-up based on the catamenial or non-catamenial nature of the disease. A PubMed/MEDLINE search was conducted using the key words: diaphragm endometriosis, thoracic endometriosis, thoracic endometriosis syndrome, catamenial pneumothorax. n/a 480 cases of thoracic endometriosis were included in this review. 61 presented with non-catamenial symptoms and 419 had catamenial symptoms. Patients were compared based on the presence of chest pain, dyspnea, hemoptysis, pneumothorax history, pneumothorax type, use and types of imaging techniques, pre- and postoperative medication, type of surgery, presence of endometriosis in pathological evaluation, location of thoracic endometriosis, follow-up period and recurrence. Types of surgeries evaluated in this review were laparoscopy (LS), laparotomy (LT), video-assisted thoracoscopic surgery (VATS), thoracotomy. A significantly higher number of patients presented with preoperative chest pain (79.7%), dyspnea (52.2%) and pneumothorax (78.9%) in the catamenial group (p <0.001). Pneumothorax occurred more frequently on the right side in both groups. 285 patients (68%) in the catamenial group received a positive imaging finding whereas this number was significantly less in the non-catamenial group (59%, p = 0.003). Majority of patients in both groups didn't receive any pre-/post-operative medication. VATS was the most common surgery in the catamenial group (56.6%). Whereas LT/LS was more frequently performed in the non-catamenial group (70.5%). Majority of the patients in both groups received a pathological finding of endometriosis Catamenial and non-catamenial nature of the disease caused a significant difference in presenting symptoms, preoperative evaluation, surgical and medical treatment and recurrence. Although most of patients presented with catamenial disease, majority of the non-catamenial patients also received a positive pathological finding. Therefore, it is important to keep thoracic endometriosis in mind when dealing with patients with non-catamenial symptoms.