Pulmonary dirofilariasis: computed tomography findings and correlation with pathologic features

OBJECTIVE: The purpose of this study was to describe the computed tomography (CT) and pathologic features of 5 nodules of pulmonary dirofilariasis in 4 patients. METHODS: Four patients with 5 nodules of pathologically confirmed pulmonary dirofilariasis who under went CT were enrolled, and the imaging interpretations were retrospectively compared with the histopathologic characteristics. RESULTS: Three of the 4 patients had a solitary nodule, and the remaining patient had 2 nodules. All the nodules were distributed in the right lower lobe and were attached to the pleura. They were all round or oval in shape and ranged in size from 11 to 22 mm in largest diameter (mean=17 mm). On thinner section CT, the nodules had a well-defined smooth margin with or without a shallow notch; they were connected to the arterial branch and, occasionally, to the venous branch. On contrast-enhanced CT, all the nodules contained a homogeneous low-attenuation area, which corresponded to areas of coagulative necrosis on histopathologic examination. CONCLUSION: Although the CT findings of a pulmonary dirofilariasis nodule are nonspecific, awareness of the findings on contrast-enhanced CT and the pathologic appearance of this rare benign condition may facilitate its differentiation from a malignant nodule.     

Partial nephrectomy for small localized renal cell carcinoma

We retrospectively reviewed the records of 54 patients with RCC who underwent partial nephrectomy for the primary lesion between 1992 and 2001. The indications for partial nephrectomy were elective in 43 and imperative in 11 patients. We selected 51 patients with clinical stage T1a who underwent open radical nephrectomy for localized RCC for comparison during the same period. We evaluated the peri- and postoperative complications, disease-free survival rates and changes of renal function in the partial nephrectomy (PN) group, compared to the radical nephrectomy (RN) group. There was no significant difference with regard to pathological findings and clinical outcomes between two groups, except for the amount of intraoperative bleeding. Three patients in the PN group developed postoperative complications, consisting of urine leakage in 2 patients and renal hypertension in 1 patient. The 5-year disease-free survival rates in the PN and RN groups were 90% and 97%, respectively. Local recurrence from the resected area of the renal parenchyma was not found in patients in the PN group. All patients in the PN group maintained satisfactory and stable renal function. In the RN group, renal function slowly deteriorated in 2 patients. Therefore, partial nephrectomy offers cancer control and an acceptable low mortality rate, comparable to those of radical nephrectomy.     

Results of adjuvant intravesical Bacillus Calmette-Guérin therapy for grade 3 superficial bladder cancer

To examine the incidence of recurrence, progression and survival in patients with grade 3 superficial bladder cancer after transurethral resection (TUR) and adjuvant intravesical instillation of Bacillus Calmette-Guérin (BCG), we retrospectively studied 39 patients with grade 3 superficial bladder cancer. Nineteen patients with high-grade superficial bladder cancer (pTa, pT1) and 5 patients with grade 3 carcinoma in situ (CIS) received intravesical instillation of BCG after transurethral resection of the bladder tumor (BCG group and CIS-BCG group). The Tokyo 172 strain BCG was given for 8 weeks, as a rule, in a dose of 80 mg in 40 ml of saline instilled into the bladder. As a control, 15 patients with grade 3 superficial bladder cancer who did not receive BCG therapy after TUR were compared (non-BCG group). Of the BCG group (n=19), 4 patients (21.1%) had recurrent tumor and 3 had invasive progression after BCG therapy and died as a result of tumor progression, while in the non-BCG group (n=15), 8 cases (53.3%) developed recurrence, only one case had progression and died of cancer. In the CIS-BCG group (n=5), 3 patients (60.0%) had recurrent tumor and 2 had invasive progression. Univariate analysis (Logrank test) demonstrated that tumor size and adjuvant instillation of BCG were associated with tumor recurrence except for carcinoma in situ, but tumor progression and survival did not differ significantly. Our results suggest that BCG therapy prevents grade 3 superficial bladder cancer (pT1, pTa) recurrence.     

Additional radical surgery after colonoscopic snare polypectomy for T1 colorectal cancer: use of the minilaparotomy approach

An additional resection is indicated when colorectal polyps resected by colonoscopy reveal T1 carcinoma with unfavorable histology (no free margin or having risk factors for lymph node metastasis). We describe our experience with this type of surgery with the minilaparotomy approach (< or = 7 cm). This prospective study included 19 consecutive patients between 1997 and 2001. Specimens resected by colonoscopy revealed T1 carcinomas with one of the following histological types: inadequate excision (no free margin), lymph-vascular invasion, histologic grade III, or sm2/sm3 (submucosal invasion greater than 200-300 microm from the muscularis mucosa). The minilaparotomy approach included 15 colectomies and 4 anterior resections. Median length of minilaparotomy was 7 cm (range, 4-7 cm). Median number of lymph nodes removed was 11 (range, 7-21 lymph nodes). Median proximal and distal margins were 9.0 (range, 5.2-17.5 cm) and 8.5 cm (range, 2.0-11.5 cm), respectively. The patients quickly returned to normal function without morbidity and mortality. Five (26.3%) had a residual carcinoma within the bowel wall, and one (5.3%) had lymph node metastasis. At a median follow-up of 33.6 months, one patient (5.3%) developed local recurrence and subsequent distant metastasis. The minilaparotomy approach is suitable for an additional operation following colonoscopic polypectomy for T1 carcinoma, thus providing a minimally invasive alternative to conventional laparotomy.     

Anesthetic management for a patient with platypnea-orthodeoxia syndrome

We experienced anesthetic management for a patient with platypnea-orthodeoxia syndrome. This syndrome is relatively uncommon and accompanies dyspnea and hypoxemia on changing to a sitting or standing from recumbent position. A 75-year-old man with the syndrome underwent atrial septal defect closure on cardiopulmonary bypass. General anesthesia was induced and maintained with midazolam, propofol, fentanyl and vecuronium bromide. During the induction, Spo2 decreased suddenly from 100% to 70%, Spo2, however, recovered to 97% immediately after changing to Trendelenburg position. The perioperative and postoperative course was uneventful, except for hypoxemia during induction. Although the exact mechanisms of platypneaorthodeoxia remains to be solved, right-to-left shunt by an anatomical abnormality and by change of the atrial septum is considered one of the hypoxic mechanisms. We suggest that it is necessary to prevent right-to-left shunt and hypoxemia in anesthetic management of a patient with platypneaorthodeoxia syndrome.     

Effect of postoperative chemotherapy on the serum alpha-fetoprotein level in hepatoblastoma

Purpose

It is generally accepted that postoperative chemotherapy does not affect the serum alpha-fetoprotein (AFP) level. The authors report on 3 patients who supposedly showed chemotherapy-related changes in their AFP levels after operation.

Methods

This study included 3 patients with hepatoblastoma (1 case of PRETEXT III and 2 cases of PRETEXT IV).

Results

One patient with PRETEXT III underwent a complete tumor resection, and the postoperative AFP level decreased until it reached the normal range. However, he consistently exhibited a transient, 2- to 3-fold increase in the AFP after each course of chemotherapy for 3 courses. The chemotherapy regimen had to be stopped because of drug-induced encephalopathy, but he has been followed up for 5 years without any evidence of recurrence, and his AFP level has also remained stable and in the normal range. Two patients with PRETEXT IV, who underwent a curative tumor resection, also showed similar chemotherapy-related changes in AFP levels. Both of these cases were observed only after the administration of routine postoperative chemotherapy instead of administering further high-dose chemotherapy. The AFP level remained stable for 17 months and 7 months after the cessation of chemotherapy in 2 cases, respectively.

Conclusions

Regarding the postoperative chemotherapy of hepatoblastoma, we have to pay close attention to both the AFP status during chemotherapy as well as the absolute AFP level.     

Prognostic factors for myasthenic crisis after transsternal thymectomy in patients with myasthenia gravis

OBJECTIVE: The purpose of this study was to assess which clinical features of patients with myasthenia gravis predict postoperative respiratory problems due to myasthenic crisis after transsternal thymectomy. METHODS: One hundred twenty-two patients who underwent transsternal thymectomy in our institute were analyzed retrospectively. Fourteen of those experienced myasthenic crisis and required prolonged (48 hours or more) postoperative mechanical ventilation. The following factors were evaluated: sex, age, body mass index, grade of symptom, disease interval, existence of thymoma, history of preoperative crisis, doses of anticholinesterase drugs, steroid use, pulmonary function, serum anti-acetylcholine receptor antibody, history of pulmonary disease, presence of other disease, operation time, and blood loss. RESULTS: Univariate analysis revealed preoperative bulbar symptoms (odds ratio = 14.246, P =.001), history of preoperative myasthenic crisis (7.091,.018), and preoperative serum level of anti-acetylcholine receptor antibody > 100 nmol/L (4.098,.044) were prognostic factors for postoperative myasthenic crisis. On the other hand, multivariate logistic regression analysis revealed preoperative bulbar symptoms (33.333,.004), preoperative serum level of anti-acetylcholine receptor antibody > 100 nmol/L (7.874,.020), and intraoperative blood loss > 1000 mL (18.519,.048) were prognostic factors for postoperative myasthenic crisis. CONCLUSIONS: In this study, postoperative myasthenic crisis after transsternal thymectomy in 122 patients with myasthenia gravis was affected by the existence of preoperative bulbar symptoms, history of preoperative myasthenic crisis, preoperative serum level of anti-acetylcholine receptor antibody > 100 nmol/L, and intraoperative blood loss > 1000 mL. Meticulous preoperative and postoperative care should be carried out to prevent postoperative myasthenic crisis in patients with these prognostic factors.     

Activation of nuclear factor-kappa B and macrophage invasion in cyclosporin A-and tacrolimus-treated renal transplants

This retrospective study was designed to compare the efficacy of cyclosporin A (CyA) and tacrolimus (FK506) on chronic rejection (CR) associated with nuclear factor-kappa B (NF-kappaB) activation and macrophage invasion. Non-episodic day 50 protocol renal biopsy was performed in 63 consecutive patients with renal transplants from living donors, treated with either CyA or FK506. Southwestern histochemistry for NF-kappaB, immunostaining for CD68, and Banff classification were performed, and these findings were compared with outcome over 34 +/- 13 months. Compared with specimens from FK506-treated patients (n = 20), specimens from CyA-treated patients (n = 43) showed a significant increase in tubulointerstitial CD68-positive cells (1.5 +/- 0.9 vs. 0.9 +/- 0.8, p < 0.01), although no significant differences were observed in NF-kappaB activation. Specimens with Banff acute rejection (AR) grade > or = 1A (n = 20) showed increased macrophages (p < 0.01) compared with specimens with AR < 1A (n = 43). Specimens from patients with clinical AR prior to day 50 biopsy (n = 23) also showed increased macrophage invasion (p < 0.01) compared with specimens from patients without prior clinical AR (n = 40). The cumulative well-functioning (serum creatinine < 1.5 mg/dL) graft survival rate was significantly lower in patients with increased tubulointerstitial CD68-positive cells (n = 63, p < 0.05). Our findings suggest that tacrolimus is more effective than CyA against CR with respect to macrophage invasion and AR.     

Bone mass increase specific to the female in a line of transgenic mice overexpressing human osteoblast stimulating factor-1

We have reported that transgenic mice overexpressing human osteoblast stimulating factor-1 (osf1) under the control of the human osteocalcin promoter have a significantly higher bone mineral content and density than nontransgenic littermates. Consequently, bone mass loss due to estrogen deficiency was compensated for in ovariectomized female mice. Here, we show that in this transgenic line, the bone mass increase was evident in female, but not male, mice, as evaluated using the ash assay, double-emission X-ray analysis, and calcein double-labeling to determine the bone formation rate. To elucidate a possible influence on gene expression, we analyzed genomic structures of the inserted transgene and its flanking regions in mouse chromosomes. The results revealed that the transgene was integrated in the mouse repetitive sequences, 234-bp-long -satellite repeats, as inverted multiple (5 + 8) copies. Twelve copies at most seemed to be functional, but no direct evidence supporting female-specific mRNA synthesis of the transgene was obtained.     

The W258X mutation in SLC22A12 is the predominant cause of Japanese renal hypouricemia

Recently, a urate transporter, hURAT1 (human uric acid transporter 1) encoded by SLC22A12, was isolated from the human kidney. hURAT1 is presumed to play the central role in reabsorption of urate from glomerular filtrate. In the present study, we analyzed SLC22A12 in seven unrelated Japanese patients with renal hypouricemia whose serum level of urate was less than 1.0 mg/dl, and their family members. We performed direct DNA sequencing of the exon and exon-intron boundaries of SLC22A12 using genomic DNA. Six of the seven patients (86%) possess mutations in SLC22A12. In five patients, a homozygous G to A transition at nucleotide 774 within exon 4 of SLC22A12, which forms a stop codon (TGA) at codon 258 (TGG), was identified (W258X). In one patient, the C to T transition within exon 3, which changes threonine at codon 217 to methionine (T217 M), and the W258X mutation were found (compound heterozygote). Thus, among 12 mutational alleles in six patients, 11 were the W258X mutation (92%). Family members with the heterozygous W258X mutation (carriers) show relatively low levels of serum urate. The present study demonstrates that homozygous W258X mutation is the predominant genetic cause of idiopathic renal hypouricemia in Japanese patients.