Blockade of NF-kappaB activity in human prostate cancer cells is associated with suppression of angiogenesis, invasion, and metastasis

Since the NF-kappaB/relA transcription factor is constitutively activated in human prostate cancer cells, we determined whether blocking NF-kappaB/relA activity in human prostate cancer cells affected their angiogenesis, growth, and metastasis in an orthotopic nude mouse model. Highly metastatic PC-3M human prostate cancer cells were transfected with a mutated IkappaBalpha (IkappaBalphaM), which blocks NF-kappaB activity. Parental (PC-3M), control vector-transfected (PC-3M-Neo), and IkappaBalphaM-transfected (PC-3M-IkappaBalphaM) cells were injected into the prostate gland of nude mice. PC-3M and PC-3M-Neo cells produced rapidly growing tumors and regional lymph node metastasis, whereas PC-3M-IkappaBalphaM cells produced slow growing tumors with low metastatic potential. NF-kappaB signaling blockade significantly inhibited in vitro and in vivo expression of three major proangiogenic molecules, VEGF, IL-8, and MMP-9, and hence decreased neoplastic angiogenesis. Inhibition of NF-kappaB activity in PC-3M cells also resulted in the downregulation of MMP-9 mRNA and collagenase activity, resulting in decreased invasion through Matrigel. Collectively, these data suggest that blockade of NF-kappaB activity in PC-3M cells inhibits angiogenesis, invasion, and metastasis.

Progression rate of ALSFRS-R at time of diagnosis predicts survival time in ALS

The authors calculated the progression rate (DeltaFS) using the total revised ALS Functional Rating Scale (ALSFRS-R) and symptom duration at diagnosis in 82 Japanese patients with ALS. Survival (death or tracheostomy) differed significantly with the DeltaFS and postdiagnostic period according to log-rank testing, but Cox proportional hazards modeling revealed no strong association between total ALSFRS-R and mortality, suggesting that the DeltaFS provides an additional predictive index beyond ALSFRS-R alone.

Three cDNA clones encoding mouse transplantation antigens: homology to immunoglobulin genes

We constructed cDNA libraries from poly(A)+ RNA isolated from cell lines of two different inbred strains of mice, and screened the libraries with a cDNA clone encoding a human transplantation antigen. Three cDNA clones were identified, sequenced and found to encode amino acid sequences highly homologous to portions of a known mouse transplantation antigen. Comparison of the cDNA sequences of mouse transplantation antigens with the constant region domains of the mouse immunoglobulin mu gene reveals a striking homology, which suggests that the two genes share a common ancestor. Antibody genes undergo DNA rearrangement during B cell differentiation that are correlated with their expression. In contrast, DNA blots with these cDNA probes suggest that the genes for the transplantation antigens are not rearranged in the genomes of liver or embryo cells, which express these antigens, as compared with sperm cells, which do not express these antigens. In Bam Hl-digested liver DNAs from different inbred strains of mice, 10-15 bands of hybridization were found. Accordingly, the genes encoding the transplantation antigens appear to constitute a multigene family with similar gene numbers in different mice.

Percutaneous cryosurgery for renal tumours

OBJECTIVE

To evaluate the use of percutaneous cryosurgery in the treatment of renal tumours.

MATERIALS AND METHODS

A cryoprobe using liquid nitrogen was designed. The tolerance of renal cancer cells to cooling was tested. Freezing tests on two extirpated kidneys involved with hypervascular tumour were performed in water at 40 degrees C. A clinical trial of percutaneous cryosurgery was carried out in two patients with advanced renal carcinoma.

RESULTS

The cooling function of the new probe was similar to that of a conventional probe. The tolerance test on renal cancer cells showed that the cooling temperature should be below -20 degrees C to render them necrotic. Freezing tests on two nephrectomized kidneys with hypervascular renal cancer suggested that embolization of the renal artery might be advisable before treatment. The clinical trial in two patients with advanced renal carcinoma showed that the whole kidney, including the tumour, became necrotic and shrunken post-operatively. The patients' Karnofsky performance scale showed a marked improvement 3 months after the operation, but their general condition gradually deteriorated. Patient 1 died 10 months and patient 2 died 5 months after the procedure.

CONCLUSION

Percutaneous cryosurgery was performed successfully in two patients with hypervascular renal tumours. Cryo-immunological activity was assumed to have contributed to the temporary improvement in their condition. These results suggest that percutaneous cryosurgery might be useful as minimally invasive treatment in a limited number of patients with advanced renal carcinoma.

Development of ductal carcinoma of the pancreas during follow-up of branch duct intraductal papillary mucinous neoplasm of the pancreas

BACKGROUND

Synchronous occurrence of intraductal papillary mucinous neoplasm (IPMN) and ductal carcinoma of the pancreas has been reported. Branch duct IPMNs with lower likelihood of malignancy are not submitted to resection but are followed-up, so ductal carcinoma may develop during the follow-up. The development of ductal carcinoma of the pancreas during follow-up of branch duct IPMNs was investigated.

METHODS

60 patients with branch duct IPMN who had an intraductal tumour of <10 mm on imaging examinations and a negative result for malignancy on cytological examination of the pancreatic juice were investigated. They were followed-up mainly by ultrasonography (US), and additionally by endoscopic ultrasonography (EUS), CT, magnetic resonance cholangiopancreatography (MRCP) or endoscopic retrograde cholangiopancreatography (ERCP) with cytological examination of the pancreatic juice for an average period of 87 months.

RESULTS

Ductal carcinoma of the pancreas distinct from IPMN developed in 5 of 60 (8%) branch duct IPMNs during follow-up. The 5-year rate of development of ductal carcinoma was 6.9% (95% CI 0.4% to 13.4%), the incidence of ductal carcinoma was 1.1% (95% CI 0.1% to 2.2%) per year and the standardised incidence ratio of development of ductal carcinoma was 26 (95% CI 3 to 48). Patients >70 years old developed ductal carcinoma significantly more frequently than those under 69. Four of five ductal carcinomas identified during follow-up were resectable. Cancer developed in IPMN in 2 of 60 (3%) branch duct IPMNs during follow-up.

CONCLUSIONS

During follow-up of branch duct IPMNs, ductal carcinoma of the pancreas not infrequently developed distinct from IPMN. In the follow-up of IPMN, special attention should be paid to the development of ductal carcinoma of the pancreas.

Total synthesis of ciguatoxin CTX3C

More than 20,000 people suffer annually from ciguatera seafood poisoning in subtropical and tropical regions. The extremely low content of the causative neurotoxins, designated as ciguatoxins, in fish has hampered the isolation, detailed biological studies, and preparation of anti-ciguatoxin antibodies for detecting these toxins. The large (3 nanometers long) and complicated molecular structure of ciguatoxins has impeded chemists from completing their total synthesis. Our highly convergent strategic approach featuring the chemoselective ring-closing metathesis reaction as a key tactic has enabled the total synthesis of ciguatoxin CTX3C, which will provide a practical supply for further studies.

Expression of interleukin-8 correlates with angiogenesis, tumorigenicity, and metastasis of human prostate cancer cells implanted orthotopically in nude mice

We determined whether the expression of interleukin-8 (IL-8) by human prostate cancer cells correlates with induction of angiogenesis, tumorigenicity, and production of metastasis. Low and high IL-8-producing clones were isolated from the heterogeneous PC-3 human prostate cancer cell line. The secretion of IL-8 protein correlated with transcriptional activity and levels of IL-8 mRNA. All PC-3 cells expressed both IL-8 receptors, CXCR1 and CXCR2. The low and high IL-8-producing clones were injected into the prostate of nude mice. Titration studies indicated that PC-3 cells expressing high levels of IL-8 were highly tumorigenic, producing rapidly growing, highly vascularized prostate tumors with and a 100% incidence of lymph node metastasis. Low IL-8-expressing PC-3 cells were less tumorigenic, producing slower growing and less vascularized primary tumors and a significantly lower incidence of metastasis. In situ hybridization (ISH) analysis of the tumors for expression of genes that regulate angiogenesis and metastasis showed that the expression level of IL-8, matrix metalloproteinases, vascular endothelial growth factor (VEGF), and E-cadherin corresponded with microvascular density and biological behavior of the prostate cancers in nude mice. Collectively, the data show that the expression level of IL-8 in human prostate cancer cells is associated with angiogenesis, tumorigenicity, and metastasis.

Low diastolic blood pressure, hypoalbuminemia, and risk of death in a cohort of chronic hemodialysis patients

In a previous report, we showed that nutritional status and especially serum albumin had great predictive value for death in chronic hemodialysis patients, whereas blood pressure did not. In the present study, we analyzed the causes of death in consideration of the relationship between serum albumin and blood pressure. A total of 1,243 Okinawan patients (719 males, 524 females) undergoing hemodialysis in January 1991 were followed up through the end of 1995. Three hundred forty-two of the patients died, 45 received transplants, and 12 were transferred by the end of the follow-up period. The total duration of observation was 5,110.3 patient-years. Blood pressure as well as clinical and laboratory variables were determined immediately prior to the first dialysis session in January 1991. The crude death rate was 40.0% when the diastolic blood pressure (DBP) <70 mm Hg, 35.0% at 70 to 79 mm Hg, 25.0% at 80 to 89 mm Hg, 25.0% at 90 to 99 mm Hg, and 13.0% at >100 mm Hg. The death rate showed an inverse correlation with DBP. DBP showed a significant positive correlation with serum albumin (r = 0.137, P < 0.001) and age (r = -0.325, P < 0.0001). The adjusted odds ratio (95% confidence interval) of death was 0.84 (0.71 to 0.99) with 10 mm Hg increments in DBP when the reference DBP was less than 69 mm Hg. Low DBP may be a manifestation of malnutrition and/or cardiovascular disease in chronic hemodialysis patients. Target DBP levels may be higher levels in chronic hemodialysis patients than the general population.

"Facilitated" amino acid transport is upregulated in brain tumors

The goal of this study was to determine the magnitude of "facilitated" amino acid transport across tumor and brain capillaries and to evaluate whether amino acid transporter expression is "upregulated" in tumor vessels compared to capillaries in contralateral brain tissue. Aminocyclopentane carboxylic acid (ACPC), a non-metabolized [14C]-labeled amino acid, and a reference molecule for passive vascular permeability, [67Ga]-gallium-diethylenetriaminepentaacetic acid (Ga-DTPA), were used in these studies. Two experimental rat gliomas were studied (C6 and RG2). Brain tissue was rapidly processed for double label quantitative autoradiography 10 minutes after intravenous injection of ACPC and Ga-DTPA. Parametric images of blood-to-brain transport (K1ACPC and K1Ga-DTPA, microL/min/g) produced from the autoradiograms and the histology were obtained from the same tissue section. These three images were registered in an image array processor; regions of interest in tumor and contralateral brain were defined on morphologic criteria (histology) and were transferred to the autoradiographic images to obtain mean values. The facilitated component of ACPC transport (deltaK1ACPC) was calculated from the K1ACPC and K1Ga-DTPA data, and paired comparisons between tumor and contralateral brain were performed. ACPC flux, K1ACPC, across normal brain capillaries (22.6 +/- 8.1 microL/g/min) was >200-fold greater than that of Ga-DTPA (0.09 +/- 0.04 microL/g/min), and this difference was largely (approximately 90%) due to facilitated ACPC transport. Substantially higher K1ACPC values compared to corresponding K1DTPA values were also measured in C6 and RG2 gliomas. The deltaK1ACPC values for C6 glioma were more than twice that of contralateral brain cortex. K1ACPC and deltaK1ACPC values for RG2 gliomas was not significantly higher than that of contralateral cortex, although a approximately 2-fold difference in facilitated transport is obtained after normalization for differences in capillary surface area between RG2 tumors and contralateral cortex. K1ACPC, deltaK1ACPC, and K DTPA were directly related to tumor cell density, were higher in regions of "impending" necrosis, and the tumor/contralateral brain ACPC radio-activity ratios (0 to 10 minutes) were very similar to that obtained with 0 to 60 minutes experiments. These results indicate that facilitated transport of ACPC is upregulated across C6 and RG2 glioma capillaries, and that tumors can induce upregulation of amino acid transporter expression in their supporting vasculature. They also suggest that early imaging (e.g., 0 to 20 minutes) with radiolabeled amino acids in a clinical setting may be optimal for defining brain tumors.

Inhibition of angiogenesis as a mechanism for inhibition by 1alpha-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3 of colon carcinogenesis induced by azoxymethane in Wistar rats

The effects of 1alpha-hydroxyvitamin D3[1alpha(OH)D3] and 1,25-dihydroxyvitamin D3[1,25(OH)2D3] on the incidence of colon tumors induced by azoxymethane and on the labeling index and angiogenesis of colon tumors were investigated in Wistar rats. Rats received 10 weekly injections of 7.4 mg/kg body weight of azoxymethane and i.p. injections of 1alpha(OH)D3 and 1,25(OH)2D3 at lower and higher doses every other day for 45 weeks. Prolonged administration of both 1alpha(OH)D3 and 1,25(OH)2D3 at a higher dose significantly reduced the incidence of colon tumors in week 45. However, administration of 1alpha(OH)D3 or 1,25(OH)2D3 had little or no effect on the histologic type of colon tumors and cancers. Administration of 1alpha(OH)D3 and 1,25(OH)2D3 at higher doses significantly decreased the labeling index, the immuno-histochemical staining for vascular endothelial growth factor and microvessel counts in colon tumors. Our findings suggest that both 1alpha(OH)D3 and 1,25(OH)2D3 inhibit development of colon tumors. A possible mechanism of inhibition of colon carcinogenesis by 1alpha(OH)D3 and 1,25(OH)2D3 is the inhibition of angiogenesis as well as an anti-proliferative effect.

Impact of the initial levels of laboratory variables on survival in chronic dialysis patients

Besides the age at start of dialysis and the presence of diabetes mellitus, serum albumin has been shown to be a significant predictor of survival in prevalent dialysis patients. However, this was not evaluated in incipient dialysis patients. The initial biochemical variables were retrieved for a large dialysis population (N = 1,982) who were started on chronic dialysis in Okinawa, Japan from 1971 to 1990. Biochemical data that included blood urea nitrogen, serum creatinine, serum electrolytes (sodium, potassium, calcium, and phosphate), total cholesterol, triglyceride, total protein, serum albumin, and hematocrit obtained just before the first dialysis session were available for 1,491 (75.2%) patients. Six hundred sixty-four (43.2%) patients died by the end of 1993. Cox proportional analysis adjusted for sex, age, year of start of dialysis, presence of diabetes mellitus, and the laboratory variables was performed to examine the significance of the initial biochemical data on survival. The risk ratio was 0.577 (P = 0.0025) in serum albumin, 1.291 (P = 0.0138) in serum potassium, and 0.966 (P = 0.0202) in serum sodium. The study results support the notion that nutritional status is important for survival in chronic dialysis patients. Causes of hypoalbuminemia, hyperkalemia, and hyponatremia should be evaluated carefully at initiation of dialysis.

Cytologic examination of pancreatic juice for differential diagnosis of benign and malignant mucin-producing tumors of the pancreas

BACKGROUND

A new clinical type of pancreatic tumor, the mucin-producing tumor, has been recognized recently. However, it is not always easy to distinguish benign from malignant tumors preoperatively. In this study, three different methods of differentiating mucin-producing tumors of the pancreas were compared.

METHODS

Endoscopic ultrasonography, endoscopic retrograde pancreatography, and cytologic examination of pancreatic juice were performed in 14 patients who had mucin-producing pancreatic tumors (11 carcinomas and 3 adenomas). Pancreatic juice was collected endoscopically without papillotomy.

RESULTS

The sensitivity, specificity, and overall accuracy of endoscopic ultrasonography were 82%, 90%, and 79%, respectively; those of endoscopic retrograde pancreatography were 91%, 91%, and 86%; and those of cytologic examination were 91%, 100%, and 93%.

CONCLUSION

Cytologic examination of pancreatic juice was the best of these three methods for differentiating benign from malignant mucin-producing pancreatic tumors.

Cytologic examination of pure pancreatic juice in the diagnosis of pancreatic carcinoma. The endoscopic retrograde intraductal catheter aspiration cytologic technique

BACKGROUND

Although cytologic examination of pure pancreatic juice obtained with a duodenofiberscope has been useful for the diagnosis of pancreatic carcinoma, the rate of false-negative results is reported to be high. To eliminate these false-negative results, the authors developed a new technique, endoscopic retrograde intraductal catheter aspiration cytology, especially for an accurate cytologic diagnosis of carcinoma of the body or tail of the pancreas.

METHODS

The accuracy of conventional cytologic examination of pure pancreatic juice was assessed in 25 patients with pancreatic carcinoma, 29 patients with pancreatitis, and 52 control subjects. Pure pancreatic juice was collected from the pancreatic duct by endoscopic cannulation using a videoimaging duodenoscope after intravenous administration of secretin. The new endoscopic retrograde intraductal catheter aspiration technique was used in four patients with carcinoma of the body or tail of the pancreas and five patients with localized pancreatitis in whom a correct diagnosis was not made by previous cytologic examination of pure pancreatic juice.

RESULTS

Positive cytologic findings were obtained in 76% of the patients with pancreatic carcinoma. Positive cytologic results were more frequent in patients with carcinoma of the head of the pancreas than in those with carcinoma of the body or tail. By the new technique, positive cytologic results were obtained in all of the patients with pancreatic carcinoma. This technique caused no severe complications.

CONCLUSIONS

This procedure of endoscopic retrograde intraductal catheter aspiration cytology seems useful for diagnosis of pancreatic carcinoma.

Endoscopic ultrasonography in diagnosis and staging of pancreatic cancer

The accuracy of endoscopic ultrasonography (EUS) for diagnosis of pancreatic cancers was evaluated in consecutive 232 patients with possible pancreatic cancer, and that for assessment of their locoregional spread was evaluated in 28 patients with pancreatic cancer subjected to pancreatectomy, in comparison with the accuracies of transabdominal ultrasonography (US) and computed tomography (CT). EUS was found to be significantly more accurate than US or CT and was especially useful for detecting small pancreatic cancers of less than 2 cm in diameter. With EUS, pancreatic cancers could be detected as a hypoechoic mass with a relatively unclear margin and irregular internal echoes. EUS was also more sensitive than CT and US for detecting venous and gastric invasions: it was more useful for detecting direct invasion of pancreatic cancers when the tumors were less than 3 cm in diameter. These findings indicate that EUS is an accurate method for diagnosis of pancreatic cancer and assessment of their locoregional spread and is particularly useful for detecting small tumors.

An epidemiologic analysis of end-stage lupus nephritis

We analyzed 566 patients (515 females and 51 males) with systemic lupus erythematosus who were treated in Okinawa, Japan, from 1972 to 1991 and followed until April 1993. One hundred four patients (95 females and 9 males) died, and 51 were considered to have end-stage lupus nephritis. The annual incidence and prevalence, per million population in each sex, were increased from 16.0 and 66.0 in 1972 to 46.7 and 683.9 in 1991 in the female patients, and from 4.2 and 8.3 in 1973 to 8.3 and 70.0 in 1991 in the male patients, respectively. Cox proportional hazard analysis was done to determine the effects of several covariates on patients and renal survival. The patients' survival rate improved, as the hazard ratio (HR) was decreased to 0.69 (year of diagnosis, 1982 to 1986) and to 0.48 (year of diagnosis, 1987 to 1991) when the HR in patients diagnosed before 1981 was taken as 1.00. Similarly, we examined renal survival by using the Cox proportional model. For this analysis, the date of start of dialysis therapy was regarded as the time of renal death. Male patients had significantly poor renal survival; the HR was 3.64 (95% confidence interval, 1.89 to 6.98) when the HR in the females was taken as 1.00. However, age at diagnosis and year of diagnosis did not significantly affect renal survival. The cumulated incidence of end-stage lupus nephritis from the time of diagnosis of systemic lupus erythematosus was 3.1% at 5 years, 9.4% at 10 years, 15.5% at 15 years, and 21.0% at 20 years.(ABSTRACT TRUNCATED AT 250 WORDS)

Diagnosis of pancreatic cancer by detecting telomerase activity in pancreatic juice: comparison with K-ras mutations

OBJECTIVE

Telomerase activity is reported to be specific and very frequent in human malignancy. K-ras mutations are also very frequently detected in pancreatic cancer, but their specificity for pancreatic cancer is controversial. We examined the telomerase activity and K-ras mutations in pancreatic juice from patients with pancreatic disease.

METHODS

Pancreatic juice was obtained endoscopically at endoscopic retrograde pancreatography from 10 patients with pancreatic cancer, three with chronic pancreatitis, and three with a normal pancreas. The telomerase activity in pancreatic juice was assayed by telomeric repeat amplification protocol. K-ras mutations in exon 1 codon 12 were examined by the two-step polymerase chain reaction combined with restriction enzyme digestion, followed by single-strand conformation polymorphism analysis and direct sequencing.

RESULTS

Telomerase activity of >5.0 was detected in eight of 10 (80%) subjects with pancreatic cancer, but in none with chronic pancreatitis or normal pancreas. K-ras mutations were detected not only in eight of 10 (80%) subjects with pancreatic cancer but also in two of three with chronic pancreatitis and in one of three with a normal pancreas.

CONCLUSIONS

It was shown that the detection of telomerase activity in pancreatic juice is a more useful diagnostic tool for pancreatic cancer than that of K-ras mutations.

Inhibition by ginsenoside Rg3 of bombesin-enhanced peritoneal metastasis of intestinal adenocarcinomas induced by azoxymethane in Wistar rats

The effects of concomitant use of bombesin and ginsenoside Rg3 on the incidence of peritoneal metastasis of intestinal adenocarcinomas induced by azoxymethane were investigated in male inbred Wistar rats. From the start of the experiment, rats were given weekly s.c. injections of azoxymethane (7.4 mg/kg body weight) for 10 weeks and s.c. injection of bombesin (40 microg/kg body weight) every other day, and from week 20, s.c. injections of ginsenoside Rg3 (2.5 or 5.0 mg/kg body weight) every other day until the end of the experiment in week 45. Bombesin significantly increased the incidence of intestinal tumors and cancer metastasis to the peritoneum in week 45. It also significantly increased the labeling index of intestinal cancers. Although administration of a higher dose of ginsenoside Rg3 with bombesin had little or no effect on the enhancement of intestinal carcinogenesis by bombesin, the location, histologic type, depth of involvement, infiltrating growth pattern, labeling and apoptotic indices and tumor vascularity of intestinal cancers, it significantly decreased the incidence of cancer metastasis. These findings indicate that ginsenoside Rg3 inhibits cancer metastasis through activities that do not affect the growth or vascularity of intestinal cancers.

A new model of white matter injury in neonatal rats with bilateral carotid artery occlusion

Periventricular leukomalacia is an important cause of cerebral palsy and characterized by cysts and coagulation necrosis in the periventricular white matter. Since no model of periventricular leukomalacia has been established in small animals, it is expected to establish a new model of white matter injury in immature rodents. Bilateral carotid arteries were occluded in neonatal rats at 5 days of age, and the brain neuropathologically examined at 7 days of age. Among 22 brains histologically examined, 20 (90.9%) had white matter changes including coagulation necrosis and cystic lesions in and around the internal capsule, while only two had small cerebral infarction and five showed some ischemic neurons in the cerebral cortex. Cerebral blood flow (CBF) decreased to about 25% of controls in the subcortical white matter in the animals with bilateral carotid artery occlusion (BCAO). Amyloid precursor protein (APP) immunohistochemistry demonstrated various APP-immunoreactive axonal profiles in the internal capsule and the subcortical white matter, and stronger expression of APP in pyramidal neurons in the cerebral cortex of BCAO brains. These results indicated that the white matter is more vulnerable than the cerebral cortex in 5-day-old rats when CBF decreases to about 25% and suggested that this model is useful for investigating the white matter changes induced by cerebral hypoperfusion in the neonatal brain, since previous models of hypoxic-ischemic brain injury in neonatal mice and rats revealed preferential susceptibility of the gray matter. It was also indicated that APP is a sensitive marker for mild axonal disruption in the white matter of the immature brain.

Up-regulation of vascular endothelial growth factor induced by hepatocyte growth factor/scatter factor stimulation in human glioma cells

Recent findings suggest that hepatocyte growth factor/scatter factor (HGF/SF) contributes to the malignant progression of human gliomas. We investigated the effect of HGF/SF on vascular endothelial growth factor (VEGF) expression of c-Met/HGF receptor-positive human glioma cell lines. Treatment of the glioma cells with various concentrations of HGF/SF resulted in an enhanced secretion of VEGF proteins accompanying increased transcription of VEGF mRNA in a dose-dependent fashion. Since malignant gliomas frequently co-express HGF/SF and its receptor, these results suggest that HGF/SF could act as an indirect angiogenic factor through autocrine induction of VEGF expression and secretion in malignant gliomas.

Pulmonary function after segmentectomy for small peripheral carcinoma of the lung

OBJECTIVE

The aim of this study is to compare the pulmonary function after a segmentectomy with that after a lobectomy for small peripheral carcinoma of the lung.

PATIENTS AND METHODS

Between 1993 and 1996, segmentectomy and lobectomy were performed on 48 and 133 good-risk patients, respectively. Lymph node metastases were detected after the operation in 6 and 24 patients of the segmentectomy and lobectomy groups, respectively. For bias reduction in comparison with a nonrandomized control group, we paired 40 segmentectomy patients with 40 lobectomy patients using nearest available matching method on the estimated propensity score.

RESULTS

Twelve months after the operation, the segmentectomy and lobectomy groups had forced vital capacities of 2.67 +/- 0.73 L (mean +/- standard deviation) and 2.57 +/- 0.59 L, which were calculated to be 94.9% +/- 10.6% and 91.0% +/- 13.2% of the preoperative values (P =.14), respectively. The segmentectomy and lobectomy groups had postoperative 1-second forced expiratory volumes of 1.99 +/- 0.63 L and 1.95 +/- 0.49 L, which were calculated to be 93.3% +/- 10.3% and 87.3% +/- 14.0% of the preoperative values, respectively (P =.03). The multiple linear regression analysis showed that the alternative of segmentectomy or lobectomy was not a determinant for postoperative forced vital capacity but did affect postoperative 1-second forced expiratory volume.

CONCLUSION

Pulmonary function after a segmentectomy for a good-risk patient is slightly better than that after a lobectomy. However, segmentectomy should be still the surgical procedure for only poor-risk patients because of the difficulty in excluding patients with metastatic lymph nodes from the candidates for the procedure.