Noriyoshi Sawabata

WT1 IgG antibody for early detection of nonsmall cell lung cancer and as its prognostic factor

There are urgent needs to develop methods for early detection of nonsmall cell lung cancer (NSCLC) because of its increasing incidence and poor prognosis. Here, we analyzed the production of IgG antibody (WT1 Ab) against WT1 (Wilms tumor gene) protein that was overexpressed in the majority of NSCLC. Enzyme‐linked immuno‐sorbent assay showed that WT1 Ab was produced in all of 91 NSCLC patients and 70 healthy individuals and that WT1 Ab titers were significantly higher in NSCLC patients compared with healthy individuals. When the cut‐off level of WT1 Ab titers were fixed at mean + 3SD of those in healthy individuals, 26.4% of NSCLC patients had WT1 Ab titers over the cut‐off level, and positive rates of WT1 Ab at each clinical stage were 25.0, 30.8 and 38.4% in stage I, II and III NSCLC, respectively. When WT1 Ab was combined with CEA or CYFRA for detection of NSCLC, positive detection rates increased from 25.0 to 34.1 and 31.8%, respectively, in stage I and from 38.4 to 69.2 and 46.1%, respectively, in stage III, but not changed in stage II. Western blot analysis showed that dominant subclass of WT1 Ab was Th1‐type IgG2. Interestingly, elevation of WT1 Ab titers was significantly associated with longer disease‐free survival in patients with stages I–III NSCLC. These results showed that WT1 Ab could be a useful marker for early detection of NSCLC and its prognostic prediction. These results also suggested that WT1‐specific immune responses played an important role in anti‐cancer immunity in NSCLC.

Cytologically malignant margin without continuous pulmonary tumor lesion: cases of wedge resection, segmentectomy and lobectomy

The surgical margin is usually investigated during the operation using a pathological method, though cytological methods are also used to identify remaining malignant cells. We reviewed cases of pulmonary resection for a malignant tumor. At our institution, an on-site surgical margin examination using a cytological method is mandated for cases of wedge resection and segmentectomy, and an option in lobectomy cases. We examined 21 wedge resection (3 primary lung cancer, 18 metastasis), 17 segmentectomy (13 primary lung cancer, 4 metastasis), and 4 lobectomy (all primarily lung cancer) cases. Six cases showed malignant cells in the surgical margin, of which one had a microscopic skip lesion pattern and five an occult pattern (positive cytology, negative pathology). Cytological malignancy occurred even in cases of wedge resection of a tiny (4 mm in diameter) lesion metastasized from colon cancer, as well as segmentectomy with a sufficient gross margin containing microscopic skip lesions and right middle lobectomy with an additional right upper lobectomy due to two previous cytological malignancies in a residual lobe. Surgical margin cytology revealed remaining malignancy in the residual lobe, which provided important information for deciding additional procedures during surgery.

Acid regurgitation associated with persistent cough after pulmonary resection: an observational study

BackgroundFollowing a pulmonary resection, some patients suffer from persistent coughing, which may have a relationship with acid regurgitation. Since few physiological studies have been reported regarding this issue, we conducted the present observational study.MethodsPersistent cough after pulmonary resection (CAP) was defined as non-productive coughing that occurred after a pulmonary resection in patients with stable chest X-ray results and no postnasal drip syndrome, asthma, or history of angiotensin converting enzyme inhibitor administration. A 24-hour esophageal pH monitor was used with patients with coughing (n = 13) and patients with no coughing (n = 4) after undergoing a lobectomy, and the relationship between acid regurgitation and CAP was assessed using symptom association probability.ResultsBased on the results of pH monitoring conducted within 4 weeks of the operation we divided the patients into 3 groups: Type A had frequent gastroesophageal refluxes (>50 occurrences in 24 hours) and frequent coughing (>30 occurrences in 24 hours), Type B had frequent gastroesophageal refluxes and infrequent coughing, and type C had infrequent gastroesophageal refluxes and infrequent coughing. Type A patients (n = 10) were exclusively those with CAP and the symptom association probability was greater than 95%. Five from that group underwent esophageal pH monitoring more than 1 year after surgery and none showed significant improvements in acid regurgitation.ConclusionThere was a relationship seen between acid regurgitation and CAP in some patients shortly after surgery, while acid regurgitation remained unimproved after improvement of coughing in most of those 1 year after surgery.