Symptom palliation with QUAD Shot radiation therapy to penile metastasis derived from descending colon cancer: a case report

A 54-year-old man was diagnosed with descending colon cancer with metastases in the liver, para-aortic lymph nodes, and penis, and chemotherapy was introduced after construction of a colostomy. The patient reported only mild penile pain at the time of diagnosis; however, the pain gradually worsened and interfered with his daily life. Opioids did not provide sufficient analgesia, and the patient developed dysuria and priapism. Through construction of a cystostomy, palliative radiotherapy with QUAD Shot regimen (14 Gy in 4 fractions twice-daily on 2 days repeated every 4 weeks) to the penile metastasis was started for pain relief and tumor shrinkage. The radiation rapidly improved the penile symptoms, enabling opioid reduction and cystostomy removal. The patient remained pain-free and able to urinate on his own until his death. Metastatic penile tumors are rare, especially those derived from colon cancer. Penile metastases occur mainly in the late stages of cancer and may impair the patient's quality of life. In such cases, palliative radiotherapy, especially with QUAD Shot regimen, is useful with short treatment time, durable symptom control, and little adverse effect, maintaining quality of life.

Prognostic significance of CD8+ tumor‑infiltrating lymphocytes and CD66b+ tumor‑associated neutrophils in the invasive margins of stages I‑III colorectal cancer

Tumor-infiltrating immune cells play an essential role in cancer progression and may help supplement the Tumor, Node, Metastasis (TNM) classification for cancer prognosis. Currently, there are numerous conflicting reports discussing the significance of tumor-associated neutrophils (TANs) in colorectal cancer (CRC). In particular, the role of TANs in the invasive margin is unclear. The present study investigated the prognostic significance of CD66⁺ TANs and CD8⁺ tumor-infiltrating lymphocytes (TILs) in the invasive margin of 103 patients with CRC. By using immunohistochemistry, survival analysis was performed on CD8⁺ TILs and CD66⁺ TANs individually, as well as models including TILs and TANs simultaneously. The findings indicated that the densities of CD8⁺ TILs and CD66b⁺ TANs in the invasive margin may provide significant prognostic value for predicting survival. Moreover, the combined evaluation of CD8⁺ TILs and CD66b⁺ TANs in the invasive margin could further improve the validity for the prediction of oncological outcomes. In addition, multivariate analysis revealed that simultaneous low tumor infiltration by CD8⁺ TILs and CD66b⁺ was an independent predictive factor for overall survival (HR=4.17, 95% CI, 1.55-12.5; P=0.004) and disease-free survival (HR=2.75, 95% CI, 1.27-6.12; P=0.01). Given the importance of CD8⁺ TILs and CD66b⁺ TANs in the tumor microenvironment, the assessment of their densities in the invasive margin may serve as a valuable prognostic marker for CRC.

[Preoperative Esophageal Decompression and Enteral Nutrition Using a W-ED Tube in Patients with Esophagogastric Junction Cancer-A Case Report]

The patient was a 67-year-old male diagnosed with adenocarcinoma of the esophagogastric junction. The esophagus was markedly dilated due to severe stenosis, and aspiration pneumonia was observed. Therefore, he was treated with a W- ED tube for simultaneous esophageal decompression and enteral nutrition. Two weeks of W-ED tube placement improved esophageal dilatation and pneumonia while maintaining nutritional status; thus, he underwent proximal gastrectomy, lower esophagectomy and combined resection of distal pancreas, spleen and left crus of diaphragm with jejunal interposition reconstruction. His postoperative course was uneventful, and he was discharged 16 days after surgery without any postoperative infectious complications such as pneumonia, anastomotic leakage, pancreatic fistula and enterocolitis. In the preoperative management for patients with esophagogastric junction cancer with severe stenosis, simultaneous esophageal decompression and enteral nutrition using a W-ED tube is very useful because it can improve aspiration pneumonia, reduce the risk of anastomotic leakage by improving esophageal edema, and prevent disuse atrophy of small intestinal villi.

[A Case of Gastric Carcinoma with Lymphoid Stroma That Was Difficult to Diagnose Preoperatively]

A 71-year-old man was referred to our hospital because of a gastric submucosal tumor. Gastrointestinal stromal tumor (GIST)was diagnosed in the antrum of the stomach and local resection was undergone. At this time, upper gastrointestinal endoscopy found the gastric submucosal tumor with a size of about 5 mm on the posterior wall of the fundus, but it was followed up. The lesion had grown to a size of about 10 mm by endoscopy 2 years later, and a biopsy was performed. Gastric mucosa associated lymphoid tissue(MALT)lymphoma was diagnosed by pathological examination, and Helicobacter pylori eradication therapy was performed. Endoscopy after treatment further increased the size of the lesion to about 20 mm, and ulceration was also observed. A biopsy was performed again, and a diagnosis of poorly differentiated adenocarcinoma was made, and laparoscopic proximal gastrectomy was undergone. It was the diagnosis of gastric carcinoma with lymphoid stroma(GCLS), pT3N0M0, pStage ⅡA in the postoperative pathological examination. GCLS is a rare disease with a frequency of about 1 to 4% of all gastric cancers, and preoperative diagnosis is difficult. From the morphology and histology, the differential diagnosis from submucosal tumors and lymphomas becomes problems.

Current status of function-preserving gastrectomy for gastric cancer

Early gastric cancer (EGC) has excellent postoperative survival outcomes; thus, one of the recent keywords in the treatment of EGC is "function-preserving gastrectomy (FPG)." FPG reduces the extent of lymphadenectomy and gastric resection without compromising the long-term prognosis. Proximal gastrectomy (PG) is an alternative to total gastrectomy (TG) for EGC in the upper-third of the stomach, in which the gastric reservoir, gastric acid secretion, and intrinsic factors are maintained. Distal gastrectomy (DG) with a small remnant stomach, namely subtotal gastrectomy (STG), is another option for upper EGC, where the function of the cardia and fundus is preserved. Pylorus-preserving gastrectomy (PPG) is a good alternative to DG for EGC in the middle-third of the stomach, where pyloric function is preserved. Following elucidation of the markedly low incidences of possible metastasis to lymph node stations where dissection is omitted, the oncological safety of these FPG procedures was clarified. Nutritional advantages of PG or STG over TG have been reported; however, the standardized reconstruction methods after PG are yet to be established, and it is important to devise methods to prevent postoperative gastroesophageal reflux and anastomotic complications regardless of the reconstruction method. Nutritional benefits of PPG compared with DG have also been clarified, in which reducing postoperative gastric stasis is important. For the further spread of these FPG procedures, several issues, such as precise evaluation of preserved function, confirmation of oncological safety, and standardization of the technique, should be addressed in future prospective randomized controlled trials.

[A Case of Gastric Cancer with Extensive Lymph Node Metastasis Causing Stenosis Symptoms in the Primary pCR after Preoperative Chemotherapy]

A 65‒year‒old man was found with a circumferential type 2 tumor in the gastric antrum by upper gastrointestinal endoscopy, and biopsy revealed poorly a differentiated adenocarcinoma and HER2‒negative results. According to imaging examinations and laparoscopy, he was diagnosed with an advanced gastric cancer, classified as cT4a(SE)N3M0 and cStage Ⅲ. He underwent neoadjuvant chemotherapy(SOX regimen)because of the bulky N finding. After 2 courses of the treatment, marked reductions in the primary gastric lesion and metastatic lymph nodes were observed, although stenosis appeared at the gastric tumor site. The W‒ED tube was used to depressurize the stomach and to manage his nutrition, and the patient's surgery was conducted under good general conditions. We performed a distal gastrectomy(D2 dissection)and cholecystectomy. Histopathological examination showed no viable tumor cells in the primary gastric lesion(Grade 3). Two metastases were found in the dissected lymph nodes, although only a few cancer cells persisted. We report a case of gastric cancer in which pCR was obtained in the primary lesion, although stenosis appeared after the neoadjuvant chemotherapy.

The therapeutic strategy for advanced gastric cancer with pyloric stenosis and liver metastasis; successfully treated by gastro-jejunal bypass and chemotherapy first, followed by curative R0 resection

Background

The indication of surgical resection for liver metastasis from gastric cancer (GC) is still limited and controversial because of its more aggressive oncological characteristics than liver metastasis from colorectal cancer. Pyloric stenosis causes an inadequate oral intake and malnutrition in GC patients. We herein report a case of GC with these two factors that was successfully treated by the combination of gastro-jejunal bypass and chemotherapy, followed by curative R0 resection.

Case presentation

A 60-year-old man was diagnosed with type 2 GC with liver metastasis and pyloric stenosis, which was confirmed as the HER2-positive type. He underwent gastrojejunostomy and received capecitabine and cisplatin (XP) + trastuzumab chemotherapy. After three courses of the XP + trastuzumab regimen, shrinkage of the primary lesion and liver metastasis was confirmed and his nutritional parameters markedly improved with a stable oral intake after bypass surgery. He underwent curative R0 resection by distal gastrectomy with D2 lymphadenectomy and partial hepatectomy. Histologically, viable tumor cells were observed in less than one-third of the primary lesion, and only scar tissue without viable cancer cells was noted in the resected liver specimen. His postoperative course was uneventful, and recurrence has not been detected in the 30 months after surgery without adjuvant chemotherapy.

Conclusion

The present case report describes a successful strategy for advanced GC with pyloric stenosis and liver metastasis.

[A Surgical Case Report of Gastric Cancer Patient with Severe COPD Successfully Controlled by Preoperative Pulmonary Rehabilitation]

A 72-year-old man with a history of chronic obstructive pulmonary disease(COPD)was diagnosed with type 3 gastric cancer at the posterior wall of the gastric body. Although there was no distant metastasis in preoperative imaging tests, pulmonary function test revealed severe obstructive ventilatory impairment, suggesting that the patient had high risks of perioperative pulmonary complications. After treatment for COPD and preoperative pulmonary rehabilitation under hospitalization for 2 weeks, laparoscopic distal gastrectomy plus D2 lymphadenectomy plus Roux-en-Y reconstruction was performed. The patient showed stable respiratory condition postoperatively, and was discharged from hospital on postoperative day 12 without serious postoperative complications. It was suggested that preoperative pulmonary rehabilitation reduced postoperative pulmonary complications and allowed safe surgery in patients with severe COPD.

Functional and nutritional outcomes after gastric cancer surgery

Recent improvements in diagnostic techniques and national screening programs have resulted in increasing number of patients diagnosed with early gastric cancer (EGC). The low incidence rate of lymph node metastasis and excellent survival rates after surgical treatment for EGC enabled the reduction in the extent of lymphadenectomy and the range of gastric resection for function-preserving gastrectomy. Thus, the quality of life (QOL) of patients with gastric cancer (GC) in the curative stage can be maintained. Moreover, these function-preserving procedures have been widely performed by less invasive procedures, such as laparoscopic and robotic approaches. Pylorus-preserving gastrectomy (PPG) and proximal gastrectomy (PG) represent the two main function-preserving surgical procedures for GC. PPG is an alternative to distal gastrectomy (DG) for cT1 N0 EGC located in the middle part of the stomach. Preservation of the pyloric function is expected to prevent post-gastrectomy syndromes such as dumping syndrome. PG is an alternative to total gastrectomy (TG) and can thus be performed for cT1 N0 EGC located in the upper part of the stomach. Preservation of the residual stomach is expected to work as a reservoir for ingested food. The optimal reconstruction method after PG among the three most commonly performed procedures (esophagogastrostomy, jejunal interposition, and double-tract reconstruction) remains controversial. In addition to these three reconstruction methods, the novel double-flap technique (DFT) of esophagogastrostomy has gained attention recently because of its potential usefulness to prevent postoperative esophageal reflux. In this review article, we summarize the current evidence of PPG and PG with esophagogastrostomy by the DFT, focusing on postoperative nutrition and QOL.

Should pylorus-preserving gastrectomy be performed for overweight/obese patients with gastric cancer?

BACKGROUND

Pylorus-preserving gastrectomy is an alternative to distal gastrectomy for early gastric cancer, and is expected to have postoperative advantages including maintenance of body weight. Overweight/obesity is a risk factor for chronic disorders, including hypertension and diabetes mellitus; in these conditions, body weight control is frequently required as part of treatment. It remains unknown whether pylorus-preserving gastrectomy should be performed in overweight/obese patients because excess body weight may be maintained postoperatively.

METHODS

We retrospectively investigated body weight changes and postoperative nutritional status of overweight/obese patients who underwent laparoscopic distal gastrectomy (LDG) or laparoscopic pylorus-preserving gastrectomy (LPPG) between 2006 and 2015. Among 349 overweight patients (BMI ≥ 25 kg/m²), 101 LDG and 101 LPPG cases were compared after propensity score matching to adjust for patient characteristics.

RESULTS

The mean relative body weight ratios (postoperative/preoperative ratios) were 87.5 ± 8.0% after LDG and 89.6 ± 6.7% after LPPG (difference not significant, p = 0.088). The prealbumin level at 2 years and hemoglobin levels at 6 months, 1 year and 2 years were significantly well maintained after LPPG than after LDG. Prealbumin and hemoglobin levels at 2 years had almost returned to baseline levels in the LPPG group. The superiority of LPPG in the hemoglobin level was confirmed regardless of reconstruction methods after LDG.

CONCLUSIONS

For overweight/obese patients, LDG and LPPG resulted in similar degrees of postoperative weight loss, with patients achieving near-ideal body weight. The postoperative nutritional advantages of LPPG were confirmed. LPPG seemed to be better even for overweight/obese patients who meet indication criteria.

Shorter Survival of Patients with Upper-Third Gastric Cancer Preoperatively Diagnosed as Stage IA Compared with Those with Middle to Lower Lesions

BACKGROUND

Although preoperatively diagnosed stage IA (cT1N0) gastric cancer includes pathologically advanced disease, patients with cT1N0 middle- to lower-third gastric cancer (MLTG) experience favorable outcomes even if they undergo gastrectomy with limited lymph node dissection; however, whether this is true for upper-third gastric cancer (UTG) patients is unknown. In this study, we examined the survival of patients with cT1N0 UTG compared with patients with MLTG.

METHODS

We retrospectively reviewed the data for 1707 consecutive patients with cT1N0 gastric cancer who underwent gastrectomy between 2006 and 2013. Patients were divided into the UTG or MLTG groups, and clinicopathological characteristics and survival were compared between the groups. Factors affecting survival were identified using multivariate analysis. Survival was calculated according to pathological findings.

RESULTS

The patient group included 334 UTG patients and 1373 MLTG patients. The 5-year overall survival (OS) of UTG patients was significantly shorter than that of MLTG patients, and UTG was identified as an independent prognostic factor of cT1N0 gastric cancer. Among UTG cases, the OS of pT2-4 or pN1-3 was significantly shorter than that of pT1 or pN0 disease. No significant differences were found between such diseases in MLTG. All relapses in UTG were distant metastases.

CONCLUSIONS

cT1N0 UTG with pT2-4 or pN1-3 are prognostic indicators of shorter OS, although MLTG of either disease is associated with favorable prognosis. Thus, UTG is an independent prognostic factor in cT1N0 gastric cancer; however, limited dissection is acceptable for cT1N0 UTG because relapses occur at distant sites.

[A Case of Laparoscopic Cholecystectomy(TANKO)for Gallbladder Cancer with Torsion]

Gallbladder torsion is comparatively rare. Gallbladder cancer is found in 1.5% of cases of acute cholecystitis. We report a case of laparoscopic cholecystectomy(TANKO)for gallbladder cancer with torsion.

CASE

A 54-year-old woman with epigastric pain underwent enhanced computed tomography. Gallbladder torsion and a tumor at the gallbladder neck were suspected, and ascites was observed. She was diagnosed with gallbladder torsion, and surgery was performed the same day. Intraoperative findings: The gallbladder was movable, minimally attached to the liver bed, rotated 360°around the cystic duct and cystic artery, and appeared necrotic. The torsion was relieved and laparoscopic cholecystectomy(TANKO)was performed. We accidentally perforated the gallbladder and bile leaked out.

COURSE

The patient did well postoperatively. Pathological diagnosis revealed gallbladder cancer.

DISCUSSION

Gallbladder cancer with torsion has been reported in 14 cases, not including ours. Among these, none were performed using laparoscopic cholecystectomy(TANKO). We believe that laparoscopic cholecystectomy is appropriate for such cases, but the approach must be carefully considered because of the risk of perforation.

Prophylactic effect of neoadjuvant chemotherapy in gastric cancer patients with postoperative complications

BACKGROUND

The occurrence of postoperative complications may have a significant negative impact on the prognosis of patients with gastrointestinal cancers. The inflammatory response releases systemic cytokines, which may induce residual cancer cell growth. Recently, neoadjuvant chemotherapy (NAC) was found to improve the prognosis of advanced gastric cancer (GC). We hypothesize that when postoperative complications occur after gastrectomy, NAC treatment of micrometastases can prevent residual cancer cell growth.

METHODS

This study included 101 patients who underwent curative resection after NAC for GC from 2005 to 2015. Clinical data, including intraoperative parameters, were collected retrospectively. Overall survival (OS) and relapse-free survival (RFS) were compared between the patients with complications and those without complications.

RESULTS

Of the 101 patients, 35 (34.7%) had grade 2 or higher complications. Among those with complications, the 3- and 5-year OS rates were 63.5 and 58.2% and the 3- and 5-year RFS rates 41.7 and 41.7%, respectively. Among those without complications, the 3- and 5-year OS rates were 65.9 and 56.3% and the 3- and 5-year RFS rates 51.1 and 43.9%, respectively. There was no significant difference in prognosis between the patients with complications and those without complications.

CONCLUSION

Our study is the first to demonstrate the potential of NAC to abolish the poor prognosis induced by postoperative complications after curative resection for GC.

Survival benefit of "D2-plus" gastrectomy in gastric cancer patients with duodenal invasion

BACKGROUND

The optimal extent of lymph node (LN) dissection for gastric cancer with duodenal invasion is yet to be clarified. This study sought to evaluate the significance of gastrectomy with D2-plus lymphadenectomy including posterior LNs along the common hepatic artery (no. 8p), hepatoduodenal ligament LNs along the bile duct (no. 12b) and those behind the portal vein (no. 12p), LNs on the posterior surface of the pancreatic head (no. 13), LNs along the superior mesenteric vein (no. 14v) and para-aortic LNs around the left renal vein (nos. 16a2 and 16b1) dissection.

METHODS

Patients with gastric cancer with duodenal invasion undergoing R0 gastrectomy from January 2000 to December 2015 were enrolled. The therapeutic value index (TVI) of each LN dissection was calculated by multiplying the incidence of metastasis to each LN station by the 5-year overall survival (OS) rate of the patients with metastasis to the station.

RESULTS

In total, 117 patients were eligible. The 5-year OS rates (and TVI) of the patients with metastasis to LNs were 40.4% (7.4) in no. 12b, 25.4% (6.8) in no. 13, 32.0% (6.1) in no. 14v, 50.0% (13.0) in no. 16a2 and 40.0% (10.0) in no. 16b1. None of the patients with metastasis in no. 8p or no. 12p survived 5 years or longer.

CONCLUSION

In a potentially curative gastrectomy for gastric cancer with duodenal invasion, there may be some survival benefit in dissection of nos. 12b, 13, 14v, 16a2 and 16b1 LNs, while no benefit was seen in dissection of nos. 8p or 12p LNs.

Impact of anatomical position of the pancreas on postoperative complications and drain amylase concentrations after laparoscopic distal gastrectomy for gastric cancer

BACKGROUND

Laparoscopic surgery for gastric cancer requires traction or compression of the pancreas, with the extent depending on the anatomical position of the pancreas. This study investigated the impact of the position of the pancreas on postoperative complications and drain amylase concentrations after laparoscopic distal gastrectomy (LDG).

METHODS

Gastric cancer patients who underwent LDG were assessed retrospectively. The following anatomical parameters were measured retrospectively in preoperative computed tomography sagittal projections: the length of the vertical line between the pancreas and the aorta (P-A length), representing the height of the slope looking down the celiac artery from the top of the pancreas, and the angle between a line drawn from the upper border of the pancreas to the root of the celiac artery and the aorta (UP-CA angle), representing the steepness of the slope. Correlations between each parameter and postoperative complications were analyzed by logistic regression analysis. Pearson's product-moment correlation coefficients were calculated for scatter diagrams for each parameter and drain amylase concentration on postoperative day 1.

RESULTS

Analyses were performed in 394 patients. P-A length [odds ratio (OR) 1.905; 95% confidence interval (CI) 1.100-3.300; P = 0.021] was significantly correlated with pancreatic fistula. P-A length (OR 2.771; 95% CI 1.506-5.098; P = 0.001), UP-CA angle (OR 2.323; 95% CI 1.251-4.314; P = 0.008), and low preoperative serum albumin (OR 2.082; 95% CI 1.050-4.128; P = 0.036) were significantly correlated with overall postoperative complications defined as Clavien-Dindo ≥ grade II. P-A length and UP-CA angle showed significant positive correlations with drain amylase concentration on postoperative day 1.

CONCLUSION

The position of the pancreas is an independent predictor of pancreatic fistula and/or postoperative complications and correlates with drain amylase concentration after LDG for gastric cancer.

[Efficacy of Palliative Radiotherapy for Unresectable Advanced Gastric Cancer with Bleeding]

Bleeding and obstruction negativelyimpact qualityof life for patients with unresectable advanced gastric cancer. There are several choices against bleeding and obstruction such as surgery, endoscopic therapy, radiotherapy and interventional radiology. We report on an 85-year-old woman with StageIV gastric cancer with tumor bleeding. Radiation therapyof 30 Gyin 10 fractions was performed. Anyadverse events were not confirmed. Bleeding or obstruction did not occur for 7 months after radiation therapy. Palliative radiation therapy to gastric cancer can be a reasonable option for patients with unsuitable general conditions for surgical intervention.

[A Case of Gemcitabine and Nab-Paclitaxel Therapy for Multiple Metastatic Pancreatic Cancer]

Pancreatic cancer is one of the leading causes of cancer-related death in Japan. Nab-paclitaxel(nab-PTX)and gemcitabine( GEM)combination chemotherapysignificantlyimproved overall survival in a phase III trial(MPACT). This combination chemotherapyhas become one of the first-line treatments for patients with metastatic pancreatic cancer since December 2014. We report a case of a patient who underwent this chemotherapyfor recurrence of pancreatic head cancer. A 64-yearold man, who underwent curative resection of pancreatic cancer 2 years ago, relapsed with multiple lung metastases and a para-aortic nodal metastasis. The patient was treated with combination chemotherapyof nab-PTX 125mg/m2 plus GEM 1,000mg/m2. He died from carcinomatous pleurisy1 9 months after starting the chemotherapy. The patient skipped scheduled chemotherapyonly3 times due to Grade 3 neutropenia during his clinical course over 19 months. The combination regimen of nab-paclitaxel and gemcitabine is thought to be a well-tolerated and standard treatment for metastatic pancreatic cancer.

"Pancreas-Compressionless Gastrectomy": A Novel Laparoscopic Approach for Suprapancreatic Lymph Node Dissection

BACKGROUND

In radical operations for gastric cancer, a balance between the quality of lymph node dissection and safety of surgery must be ensured. During suprapancreatic lymphadenectomy in laparoscopic gastrectomy (LG), an adequate operative field should be safely and effectively established to reduce pancreas-related complications. We present a novel approach that avoids direct compression of the pancreas in LG and describe the surgical outcomes of this method.

METHODS

We historically compressed the pancreas during suprapancreatic lymph node dissection in LG to obtain an adequate operative field but have since modified our operative technique. In our new method introduced in March 2016, the operative field is established by pulling and controlling the connective tissues along the inferior border of the pancreas and the nerves along the common hepatic and splenic arteries, instead of directly compressing the pancreas itself. We compared 51 patients in the compression group (January 2015-February 2016) and 45 patients in the compressionless group (March 2016-January 2017) in terms of surgical outcomes, including the amylase concentration in the drainage fluid and postoperative complications.

RESULTS

The amylase concentrations in the compressionless group were significantly lower on postoperative days 1 and 3 (p < 0.001 and p = 0.013, respectively) compared with the compression group. The rates of severe postoperative pancreatic fistula and intra-abdominal infectious complications decreased from 11.8 to 2.2% (p = 0.116) and from 17.6 and 2.2% (p = 0.018), respectively.

CONCLUSIONS

Our approach, termed "pancreas-compressionless gastrectomy," can be considered a safe and useful method to prevent postoperative infectious complications in LG.

Excellent Long-Term Prognosis and Favorable Postoperative Nutritional Status After Laparoscopic Pylorus-Preserving Gastrectomy

BACKGROUND

Laparoscopic pylorus-preserving gastrectomy (LPPG) has been introduced as a minimally invasive function-preserving operation for early gastric cancer (GC). This study aimed to investigate the surgical and prognostic outcomes after LPPG at the authors' institution.

METHODS

This study analyzed 465 patients who underwent LPPG for cT1 N0 GC located in the middle part of the stomach between 2006 and 2012. Short- and long-term surgical outcomes including 5-year survival rates, postoperative nutritional data, and body weight change were retrospectively investigated.

RESULTS

Regarding short-term surgical results, 14 (3%) of the 465 patients had severe complications classified as Clavien-Dindo grade 3a or above, and no mortality occurred (no in-hospital deaths). The median follow-up period was 1829 days (range 226-3197 days), and the 5-year overall survival and relapse-free survival rates were respectively 98% (95% confidence interval [CI] 96.1-99.0%) and 98% (95% CI 96.1-99.0%). Only two cases of postoperative recurrence were confirmed, and their recurrence sites were not in the remnant stomach or regional lymph nodes. The postoperative nutritional status, in terms of serum total protein, albumin, and hemoglobin levels, was well maintained, and the mean relative body weight (postoperative/preoperative) was 93.24 ± 7.29% after LPPG.

CONCLUSIONS

For the first time, we have clarified the detailed long-term survival outcomes of LPPG for cT1 N0 GC. LPPG is an acceptable and favorable operative method for clinically diagnosed early-stage GC, in terms of long-term survival and postoperative nutrition.

Yes-associated protein (YAP) modulates oncogenic features and radiation sensitivity in endometrial cancer

BACKGROUND

Yes-associated protein (YAP) is a transcriptional co-activator and regulates cell proliferation and apoptosis. We investigated the clinical and biological significance of YAP in endometrial cancer (EMCA).

METHODS

YAP expression in 150 primary tumor tissues from patients with EMCA was evaluated by immunohistochemistry and its association with clinicopathological data was assessed. The biological functions of YAP were determined in EMCA cell lines through knockdown/overexpression of YAP. The role of YAP in modulating radiation sensitivity was also investigated in EMCA cells.

RESULTS

Increased nuclear YAP expression was significantly associated with higher grade, stage, lympho-vascular space invasion, postoperative recurrence/metastasis and overall survival in estrogen mediated EMCA, called type 1 cancer (p = 0.019,  = 0.028,  = 0.0008,  = 0.046 and  = 0.015, respectively). In multivariate analysis, nuclear YAP expression was confirmed as an independent prognostic factor for overall survival in type 1 EMCA. YAP knockdown by siRNA resulted in a significant decrease in cell proliferation (p<0.05), anchorage-dependent growth (p = 0.015) and migration/invasion (p<0.05), and a significant increase in the number of cells in G0/G1 phase (p = 0.002). Conversely, YAP overexpression promoted cell proliferation. Clonogenic assay demonstrated enhanced radiosensitivity by approximately 36% in YAP inhibited cells.

CONCLUSIONS

Since YAP functions as a transcriptional co-activator, its differential localization in the nucleus of cancer cells and subsequent impact on cell proliferation could have important consequences with respect to its role as an oncogene in EMCA. Nuclear YAP expression could be useful as a prognostic indicator or therapeutic target and predict radiation sensitivity in patients with EMCA.

Circulating miR-18a: a sensitive cancer screening biomarker in human cancer

MicroRNAs have been reported to be stably detectable in plasma/serum and to exhibit resistance to endogenous ribonuclease activity because of binding to proteins such as Argonaute-2 and high-density lipoprotein, or being packed by secretory particles such as exosomes. These secretory particles include specific microRNAs and can function as intercellular transmitters. These findings could open-up a new and promising field in the use of circulating microRNAs for cancer treatment. In particular, miR-18a, which is located in the potentially oncogenic miR-17-92 cluster, is a highly expressed microRNAs in several types of cancers. The concentration of miR-18a in plasma/serum of patients with cancer such as esophageal (AUC=0.944), pancreatic (AUC=0.936), hepatocellular (AUC=0.881), colorectal and other types of cancers is much higher than that of healthy volunteers. Such reports provide evidence that circulating miR-18 might be a next-generation biomarker and contribute to cancer screening in non-invasive liquid biopsy, to a clinically-satisfactory degree of sensitivity and specificity.

Liquid biopsy of gastric cancer patients: Circulating tumor cells and cell-free nucleic acids

To improve the clinical outcomes of cancer patients, early detection and accurate monitoring of diseases are necessary. Numerous genetic and epigenetic alterations contribute to oncogenesis and cancer progression, and analyses of these changes have been increasingly utilized for diagnostic, prognostic and therapeutic purposes in malignant diseases including gastric cancer (GC). Surgical and/or biopsy specimens are generally used to understand the tumor-associated alterations; however, those approaches cannot always be performed because of their invasive characteristics and may fail to reflect current tumor dynamics and drug sensitivities, which may change during the therapeutic process. Therefore, the importance of developing a non-invasive biomarker with the ability to monitor real-time tumor dynamics should be emphasized. This concept, so called “liquid biopsy”, would provide an ideal therapeutic strategy for an individual cancer patient and would facilitate the development of “tailor-made” cancer management programs. In the blood of cancer patients, the presence and potent utilities of circulating tumor cells (CTCs) and cell-free nucleic acids (cfNAs) such as DNA, mRNA and microRNA have been recognized, and their clinical relevance is attracting considerable attention. In this review, we discuss recent developments in this research field as well as the relevance and future perspectives of CTCs and cfNAs in cancer patients, especially focusing on GC.

Prognostic impact of circulating miR-21 in the plasma of patients with gastric carcinoma

BACKGROUND

MicroRNAs (miRNAs) such as miR-17-5p, miR-21, miR-106a and miR-106b are reported to be highly expressed in gastric carcinoma (GC) tissues. Recently, we reported that these miRNAs were consistently detectable in plasma and reflected tumor dynamics of GC. We hypothesized that these plasma miRNA concentrations could be used as prognostic markers in patients with GC.

MATERIALS AND METHODS

Between 2008 and 2009, preoperative plasma samples were collected from 69 consecutive patients with GC at our hospital. We retrospectively examined the association between plasma miRNA concentrations and prognosis.

RESULTS

The postoperative cause-specific survival rate of patients with high plasma miR-21 concentration was significantly poorer than those with a low concentration (p=0.0451), as was that of those with high plasma concentration of miR-106a (p=0.1132). There were no prognostic differences according to the plasma concentration of miR-17-5p and miR-106b. Those with high miR-21 concentration had also a slightly higher incidence of vascular invasion (p=0.0311). Multivariate analysis revealed that the presence of a high miR-21 concentration in plasma was an independent prognostic factor (p=0.0133, hazard ratio: 13.4 (95% CI: 1.72-104.4)).

CONCLUSION

The level of circulating miR-21 could be a reliable prognostic marker in the plasma of patients with GC. These findings contribute to the stratification of patients in order to identify those who need meticulous follow-up for early detection of recurrence and additional or alternative treatments of GC.

Progression of remnant gastric cancer is associated with duration of follow-up following distal gastrectomy

AIM

To re-evaluate the recent clinicopathological features of remnant gastric cancer (RGC) and to develop desirable surveillance programs.

METHODS

Between 1997 and 2008, 1149 patients underwent gastrectomy for gastric cancer at the Department of Digestive Surgery, Kyoto Prefectural University of Medicine, Japan. Of these, 33 patients underwent gastrectomy with lymphadenectomy for RGC. Regarding the initial gastric disease, there were 19 patients with benign disease and 14 patients with gastric cancer. The hospital records of these patients were reviewed retrospectively.

RESULTS

Concerning the initial gastric disease, the RGC group following gastric cancer had a shorter interval [P < 0.05; gastric cancer vs benign disease: 12 (2-22) vs 30 (4-51) years] and were more frequently reconstructed by Billroth-I procedure than those following benign lesions (P < 0.001). Regarding reconstruction, RGC following Billroth-II reconstruction showed a longer interval between surgical procedures [P < 0.001; Billroth-II vs Billroth-I: 32 (5-51) vs 12 (2-36) years] and tumors were more frequently associated with benign disease (P < 0.001) than those following Billroth-I reconstruction. In tumor location of RGC, after Billroth-I reconstruction, RGC occurred more frequently near the suture line and remnant gastric wall. After Billroth-II reconstruction, RGC occurred more frequently at the anastomotic site. The duration of follow-up was significantly associated with the stage of RGC (P < 0.05). Patients diagnosed with early stage RGC such as stage I-II tended to have been followed up almost every second year.

CONCLUSION

Meticulous follow-up examination and early detection of RGC might lead to a better prognosis. Based on the initial gastric disease and the procedure of reconstruction, an appropriate follow-up interval and programs might enable early detection of RGC.

Differences of the lymphatic distribution and surgical outcomes between remnant gastric cancers and primary proximal gastric cancers

BACKGROUND

Although remnant gastric cancer (RGC) following distal gastrectomy is located in the proximal stomach, little is known about the differences of the lymphatic distribution and surgical outcomes between RGC and primary proximal gastric cancer (PGC).

METHODS

Between 1997 and 2008, 1,149 patients underwent gastrectomy for gastric cancer. Of these, 33 (2.9%) RGC patients and 207 (18.5%) PGC patients were treated at our department. We reviewed their hospital records retrospectively.

RESULTS

Compared with the PGC patients, those with RGC had a slightly higher age at onset (p=0.09), higher incidence of undifferentiated cancer (p=0.06), higher incidence of vascular invasion (p=0.09), and higher incidence of T4 (p=0.07). Gastrectomy for RGC involved greater blood loss (p<0.005), longer surgical duration (p=0.01), combined resection, and high incidence of complications. However, the survival rate for RGC patients was similar to that for PGC patients (p=0.67). 2) Patients with RGC had a different pattern of lymph node metastasis compared with that in PGC. Particularly in advanced RGC with pT2-T4 tumors, RGC frequently demonstrated jejunal mesentery lymph node metastases (RGC vs. PGC, 35% vs. 0%) and splenic hilar lymph node metastases (RGC vs. PGC, 17% vs. 10%). The jejunal mesentery lymph node metastases were detected only following Billroth II reconstruction (Billroth I vs. Billroth II, 0% vs. 67%).

CONCLUSION

Although the clinical behaviors of the two gastric cancers were different, the survival rates were similar. The pattern of metastasis indicates that the jejunal mesentery and splenic hilar lymph nodes should be specifically targeted for en bloc resection during complete gastrectomy in RGC.

Detection of gastric cancer-associated microRNAs on microRNA microarray comparing pre- and post-operative plasma

Background:

Recently, it was reported that plasma microRNAs (miRNAs) are low-invasive useful biomarkers for cancer. We attempted to isolate gastric cancer (GC)-associated miRNAs comparing pre- and post-operative paired plasma, thereby excluding the possible effects of individual variability.

Methods:

This study was divided into four steps: (1) microarray analysis comparing pre- and post-operative plasma; (2) validation of candidate miRNAs by quantitative RT–PCR; (3) validation study of selected miRNAs using paired plasma; and (4) comparison of the levels of selected miRNAs in plasma between healthy controls and patients.

Results:

From the results of microarray analysis, nine candidate miRNAs the levels of which were markedly decreased in post-operative plasma were selected for further studies. After confirmation of their post-operative marked reduction, two candidate miRNAs, miR-451 and miR-486, were selected as plasma biomarkers, considering the abundance in plasma, and marked decrease in post-operative samples. In validation, the two miRNAs were found to decrease in post-operative plasma in 90 and 93% of patients (both P<0.01). In comparison with healthy controls, the levels of both miRNAs were found to be significantly higher in patients, and the area under the curve values were high at 0.96 and 0.92.

Conclusion:

Plasma miR-451 and miR-486 could be useful blood-based biomarkers for screening GC.

Novel diagnostic value of circulating miR-18a in plasma of patients with pancreatic cancer

BACKGROUND

Several recent studies have demonstrated that microRNAs (miRNAs) are stably detectable in the plasma/serum. We hypothesised that miR-18a in the plasma is a potential biomarker in patients with pancreatic cancer.

METHODS

miR-18a is located in the miR-17-92 cluster and reported to be highly expressed in pancreatic cancer tissues. This study was divided into three parts: (1) Confirmation of higher miR-18a levels in primary pancreatic cancer tissues and cell lines than in normal pancreatic tissues and a human fibroblast cell line. (2) Evaluation of the plasma miR-18a assay using quantitative RT-PCR by comparing plasma results obtained from 36 patients with pancreatic cancer and from 30 healthy volunteers. (3) Evaluation of the assay for monitoring tumour dynamics in patients with pancreatic cancer.

RESULTS

(1) The expression of miR-18a was significantly higher in pancreatic cancer tissues (P=0.012) and pancreatic cancer cell lines (P=0.015) than in normal tissues and fibroblasts. (2) Plasma concentrations of miR-18a were significantly higher in pancreatic cancer patients than in controls (P<0.0001). The value of the area under the receiver-operating characteristic curve (AUC) was 0.9369. (3) Plasma levels of miR-18a were significantly lower in postoperative samples than in preoperative samples (P=0.0077).

CONCLUSION

Circulating miR-18a might provide new complementary tumour markers for pancreatic cancer.

Circulating microRNAs in plasma of patients with oesophageal squamous cell carcinoma

Background:

Several recent studies demonstrated that microRNAs (miRNAs) are stably detectable in plasma/serum. We hypothesised that plasma miRNAs concentrations contributed to potential biomarkers in patients with oesophageal squamous cell carcinoma (ESCC).

Methods:

We selected three oncogenic miRNAs (miR-21, miR-184, miR-221) and one tumour suppressive miRNA (miR-375), which are frequently reported in squamous cell carcinoma, as candidate targets for this plasma miRNA assay. This study was divided into three steps: (1) Determination of appropriate plasma miRNAs in preliminary tests. (2) Evaluation of whether the plasma miRNA assays could monitor tumour dynamics. (3) Validation study on the clinical application of plasma miRNA assays in 50 ESCC patients and 20 healthy volunteers.

Results:

(1) In preliminary tests, the plasma level of miR-21 was significantly higher (P=0.0218) and that of miR-375 (P=0.0052) was significantly lower in ESCC patients than controls. (2) The high plasma miR-21 levels reflected tumour levels in all cases (100%). The plasma level of miR-21 was significantly reduced in postoperative samples (P=0.0058). (3) On validation analysis, the plasma level of miR-21 tended to be higher in ESCC patients (P=0.0649), while that of miR-375 was significantly lower (P<0.0001) and the miR-21/miR-375 ratio was significantly higher (P<0.0001) in ESCC patients than in controls. The value of the area under the receiver-operating characteristic curve (AUC) was 0.816 for the miR-21/miR-375 ratio assay. Patients with a high plasma level of miR-21 tended to have greater vascular invasion (P=0.1554) and to show a high correlation with recurrence (P=0.0164).

Conclusion:

Detection of circulating miRNAs might provide new complementary tumour markers for ESCC.

Pleural lavage with distilled water during surgery for esophageal squamous cell carcinoma

This study aimed to investigate cytocidal effects of hypotonic shock on esophageal squamous cell carcinoma (ESCC) cell lines, and to apply pleural lavage with distilled water to surgery for ESCC. Three human ESCC cell lines, TE5, TE9 and KYSE170 were exposed to distilled water, and morphological changes in ESCC cells were closely observed under a differential interference contrast microscope connected to a high-speed digital video camera. Further, serial cell volume changes after hypotonic shock were measured using a high-resolution flow cytometer. To investigate the cytocidal effects of hypotonic shock on ESCC cells, re-incubation of ESCC cells was performed after hypotonic shock. Additionally, the effects of 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB), a Cl- channel blocker, during hypotonic shock were analyzed. Video recordings by high-speed digital camera demonstrated that hypotonic shock with distilled water induced cell swelling followed by cell rupture. Measurements of cell volume changes using a high-resolution flow cytometer indicated that severe hypotonicity with distilled water increased broken fragments of ESCC cells within 5 min. Re-incubation experiments demonstrated cytocidal effects of hypotonic shock on ESCC cells. Treatment of cells with NPPB increased cell volumes by the inhibition of regulatory volume decrease, which is observed during hypotonic shock, and enhanced cytocidal effects. These findings demonstrated the cytocidal effects of hypotonic shock on ESCC cells, and clearly support the efficacy of pleural lavage with distilled water during surgery for ESCC.

Clinical significance of vascular endothelial growth factors C and D and chemokine receptor CCR7 in gastric cancer

BACKGROUND/AIM

This study was designed to investigate the clinical significance of lymphangiogenic vascular endothelial growth factors C and D, and chemokine receptor CCR7 in the lymphatic spread of gastric cancer.

PATIENTS AND METHODS

The expressions of VEGF-C and -D, and CCR7 were examined in 82 gastric tumors showing a discrepancy between the degree of lymphatic invasion (Ly) and the status of lymph node metastasis (N) (Ly+N-: 72, and Ly-N+: 10 patients).

RESULTS

High expression of VEGF-C and -D, and CCR7 was present in 88%, 63% and 67% of cases, respectively. The VEGF-C expression was significantly higher in Ly+N- than Ly-N+ (p<0.05), but VEGF-D and CCR7 were not. CCR7 expression was a prognostic factor in the Ly+N- subgroup (p<0.05), but VEGF-C and -D were not.

CONCLUSION

VEGF-C and -D and CCR7 may play critical roles in lymphatic invasion in primary tumors. CCR7 expression should provide prognostic information in node-negative gastric cancer patients showing lymphatic invasion.

Prediction of CCND1 amplification using plasma DNA as a prognostic marker in oesophageal squamous cell carcinoma

Background:

We aimed to develop a new biomarker to predict cyclin D1 (CCND1) status using plasma DNA in oesophageal squamous cell carcinoma (ESCC) patients.

Methods:

We evaluated the ratio of the CCND1 (11q13) dosage to the dopamine receptor D2 (DRD2; 11q22-23) dosage (C/D ratio) as CCND1 copy number. This study was divided into three steps: (1) Determination of a cutoff value for the C/D ratio in test scale; (2) Comparison of the C/D ratio in between plasma samples and cancer tissues in ESCC patients showing high plasma C/D ratio; (3) Validation study of the clinical application of the plasma C/D ratio as a diagnostic and prognostic marker, by comparing with clinicopathologic factors in 96 ESCC patients.

Results:

The plasma C/D ratio was significantly higher in the ESCC group than the controls (P=0.0134). A high plasma C/D ratio reflected the tumour C/D ratio, and significantly correlated with a poorer prognosis (P=0.0186). Moreover, the high C/D ratio was found to be an independent prognostic factor on multivariate analysis (P=0.0266; hazard ratio 5.988).

Conclusion:

Prediction of CCND1 amplification using plasma DNA is thought to be a promising prognostic biomarker in ESCC patients.

Prognostic impact of lymphatic invasion in patients with node-negative gastric cancer

BACKGROUND AND OBJECTIVES

This study investigated the prognostic impact of lymphatic invasion on the outcome of patients with node-negative gastric cancer.

METHODS

A total of 828 patients with node-negative gastric cancer who underwent curative gastrectomy were reviewed retrospectively. The clinicopathological features and prognoses of patients with lymphatic invasion were compared to those of patients without such invasion.

RESULTS

The total rate of lymphatic invasion was 18.2% in node-negative gastric cancers, with a significant difference between early gastric cancers (9.8%) and advanced gastric cancers (49.2%). The presence of lymphatic invasion correlated significantly with tumor location, size and depth of tumor (P < 0.01). Lymphatic invasion was significantly associated with a poorer overall survival in node-negative gastric cancer patients on univariate analysis (P < 0.001) as well as multivariate analysis (P < 0.01).

CONCLUSIONS

Lymphatic invasion provides additional useful information that could be applied to identify patients at high risk for recurrence who might be candidates for adjuvant therapies in patients with node-negative gastric cancers.

Role of leukotriene B4 in bronchial hyperresponsiveness induced by interleukin-8

Repeated intranasal administration of interleukin 8 (IL-8) induces bronchial hyperresponsiveness (BHR) accompanied by lower airway neutrophil accumulation (ANA) in guinea-pigs. Leukotriene B4 (LTB4) is a chemotactic factor for neutrophils. To elucidate whether LTB4 and neutrophil elastase are involved in the IL-8-induced BHR and ANA, the effects of a LTB4 antagonist (ONO-4057) and a neutrophil elastase inhibitor (ONO-5046) on the responses were examined. IL-8 (5 microg x kg[-1]) was administered intranasally to guinea-pigs twice weekly for 3 weeks. One day after the last administration, animals were anaesthetized and artificially ventilated through tracheal cannulae, and lateral pressure at the tracheal cannula (Pao) was measured as an overall index of airway responses to inhaled histamine. ONO-4057 (2 or 20 mg x kg[-1]) or ONO-5046 (30 or 300 mg x kg[-1]) was administered intraperitoneally 24 and 1 h before anaesthesia. ONO-4057, but not ONO-5046, significantly inhibited the IL8-induced BHR and ANA, assessed by bronchoalveolar lavage, in a dose-dependent manner. These findings suggest that interleukin 8 causes bronchial hyperresponsiveness and airway neutrophil accumulation in guinea-pigs in vivo. In part this appears to be due to release of leukotriene B4, whereas it may not be mediated by neutrophil elastase.

Effect of surfactant inhalation on allergic bronchoconstriction in guinea pigs

BACKGROUND

In the small airway, surfactant reduces surface tension, prevents liquid filling of bronchioles, thereby maintaining patency in the small airways. Recent reports demonstrated that surfactant dysfunction develops in experimental asthma in immunized guinea pigs. However, there are few reports concerning surfactant and lung function in an experimental asthma model.

OBJECTIVE

To examine whether inhaled surfactant improves lung mechanics in antigen-induced bronchoconstriction in guinea pigs.

METHOD

We developed a passively immunized guinea pig model for allergic bronchoconstriction induced by antigen inhalation. Using this model, we investigated the effect of inhaled exogenous surfactant, surfactant TA, on the airway opening pressure (Pao) after antigen challenge.

RESULTS

Aerosol antigen challenge produced a gradual and long-lasting increase in Pao. Twenty minutes after antigen challenge, aerosolized surfactant TA, 20 mg/ml, was inhaled for 90 s, and it significantly reduced the Pao by 32.8% in 12 min, while a 10.2% reduction was observed in a control group in the same period. When surfactant TA was administered by 90-s inhalation before antigen challenge, it inhibited the Pao increase in a dose-dependent manner: mean inhibitory rates of Pao were 33.6% in surfactant TA 10 mg/ml and 61.9% in surfactant TA 20 mg/ml, respectively.

CONCLUSION

Inhaled surfactant showed preventive and recovery effects on antigeninduced bronchoconstriction in an immunized guinea pig model.

Role of sensory neuropeptides in post-allergic propranolol-induced bronchoconstriction in guinea pigs in vivo

BACKGROUND

Administration of propranolol can provoke bronchoconstriction in asthmatic patients. We hypothesized that such bronchoconstriction may result from the inflammatory mediators released by an allergic reaction. We recently developed a guinea pig model for propranolol-induced bronchoconstriction (PIB). Neuropeptides which are released from C-fibre nerve endings have been postulated to induce bronchial hyperresponsiveness through neurogenic inflammation.

OBJECTIVE

The purpose of this study was to examine whether sensory neuropeptides are involved in the development of PIB after allergic reaction.

METHODS

Propranolol at a concentration of 10 mg/ml was inhaled 20 min after antigen challenge in passively sensitized, anaesthetized and artificially ventilated guinea pigs. The animals were treated intravenously with a NK1 and NK2 dual antagonist, FK224, in a dose of 1 or 10 mg/kg or vehicle or a selective NK1 antagonist, FK888, in a dose of 1 or 10 mg/kg or vehicle 10 min before or 15 min after antigen challenge.

RESULTS

Propranolol inhaled 20 min after antigen challenge caused bronchoconstriction. FK224 or FK888 administered 15 min after antigen challenge as well as 10 min before antigen challenge did not reduce the PIB.

CONCLUSION

We conclude that neuropeptides such as neurokinin A and substance P do not directly contribute to the development of PIB after allergic reaction.

Involvement of PAF in postallergic propranolol-induced bronchoconstriction in guinea-pigs

Administration of propranolol can provoke bronchoconstriction in asthmatic patients. Recently, we successfully developed a guinea-pig model for propranolol-induced bronchoconstriction (PIB). We hypothesized that such bronchoconstriction may result from the inflammatory mediators released by an allergic reaction. The purpose of this study was to examine the role of platelet-activating factor (PAF) in the development of PIB after allergic reaction. Propranolol, at a concentration of 10 mg.mL-1 was inhaled 20 min after antigen challenge in passively sensitized, anaesthetized and artificially-ventilated guinea-pigs. The animals were treated intravenously with PAF antagonists, E6123 (1 and 10 micrograms.kg-1) or Y-24180 (1 and 10 mg.kg-1), 10 min before or 15 min after antigen challenge. Propranolol inhaled 20 min after antigen challenge caused bronchoconstriction. E6123 and Y-24180 administered 15 min after antigen challenge as well as 10 min before antigen challenge reduced the PIB in a dose-dependent manner. We conclude that platelet-activating factor may contribute to the development of propranolol-induced bronchoconstriction after allergic reaction in our guinea-pig model.

Sensory neuropeptides are not directly involved in bronchial hyperresponsiveness induced by interleukin-8 in guinea-pigs in vivo

BACKGROUND

Interleukin-8 (IL-8) has been shown to be a chemotactic factor for neutrophils, T-lymphocytes and eosinophils. Repeated intranasal administration of IL-8 enhances bronchial responsiveness to inhaled histamine in guinea-pigs. Neuropeptides which are released from C-fibre nerve-endings have been postulated to induce bronchial hyperresponsiveness through neurogenic inflammation.

OBJECTIVE

This study was conducted to examine whether sensory neuropeptides are involved in the IL-8-induced bronchial hyperresponsiveness.

METHODS

IL-8 at a dose of 5 micrograms/kg was administered intranasally to guinea-pigs twice a week for 3 weeks. One day after the last administration, animals were anesthetized and artificially ventilated through tracheal cannula, and lateral pressure at the tracheal cannula (Pao) was measured as an overall index of airway responses to increasing concentrations of inhaled histamine (25, 50, 100, and 200 micrograms/mL). A NK1 and NK2 dual antagonist FK224 (10 mg/kg), a selective NK1 antagonist FK888 (10 mg/kg) or vehicle was intravenously administered 10 min before measurement of bronchial responsiveness.

RESULTS

The IL-8 treatment significantly enhanced bronchial responsiveness to histamine (ANOVA P < 0.01). FK224 or FK888 did not alter the IL-8-induced bronchial hyperresponsiveness.

CONCLUSION

We conclude that repeated intranasal administration of IL-8 causes bronchial hyperresponsiveness (BHR) and that neuropeptides such as neurokinin A and substance P do not directly contribute to the development of BHR induced by IL-8.