A case of Birt-Hogg-Dubé syndrome implying reduced or no wild-type folliculin without mutated protein is pathogenic

Birt-Hogg-Dubé syndrome (BHDS) is an autosomal dominant cancer syndrome caused by a germline mutation of the folliculin (FLCN) gene. Previous studies have suggested that truncated mutant folliculin proteins generated by disease causing FLCN mutations may retain partial functionality and contribute to disease phenotype. A 38-year-old Russian man presented with a left renal tumor. He underwent a left radical nephrectomy and histological examination confirmed the diagnosis of chromophobe renal cell carcinoma. He had papulae on his face suggestive of fibrofolliculomas, and pulmonary cysts on his computed tomography of the chest. He had a family history of skin manifestations. Genetic analysis identified a genomic deletion including the putative promoter region of FLCN exon 1 in the germline, and the second hit on the remaining wild-type FLCN in the renal carcinoma cells, which is expected to cause the complete lack of folliculin protein. Immunohistochemistry with the use of anti-folliculin antibody showed no antibody-binding on chromophobe renal carcinoma cells. These findings suggest that the decreased FLCN expression itself without producing mutated folliculin proteins can be at risk for developing clinical manifestations of BHDS: fibrofolliculomas, lung cysts, and tumorigenesis in the kidneys. This sheds light on the pathogenesis of BHDS and the role of FLCN as a tumor suppressor gene.

Quantitative evaluation of age-related changes to pelvic floor muscles in magnetic resonance images from 369 patients

AIM

This study aimed to establish and validate a quantitative evaluation method for pelvic floor muscles using magnetic resonance images (MRI) and to examine the morphological change of pelvic floor muscles with aging.

METHODS

Data from 369 consecutive patients (163 men, 206 women; median age 58 years; range 17-92 years) who underwent coronal T2-weighted pelvic MRI at Osaka General Hospital between January 2016 and December 2016 were retrospectively examined. MRI of the levator ani muscle was evaluated. The MRI image blinded the patient information and was evaluated by a radiology specialist with 22 years of experience. In coronal T2-weighted MRI of the pelvis, the levator ani muscle was evaluated using the slice; it showed the most upward and downward convexity. We measured the thickness of the levator ani muscle, and the distance at the most convex part from a straight line connecting the origin and insertion of the levator ani muscle on both the left and right sides. Upward and downward convexity was recorded in positive and negative values, respectively.

RESULTS

The levator ani muscle was able to be evaluated quantitatively in all cases. Both men and women showed thinning (men: mean 3.316 mm, r = -0.388, P < 0.0001; women: mean 3.947 mm, r = -0.359, P < 0.0001) and concavity (men: mean 1.412 mm, r = -0.362, P < 0.0001; women: mean 4.979 mm, r = -0.630, P < 0.0001) of the levator ani muscle with aging.

CONCLUSIONS

A quantitative evaluation method for pelvic floor muscles using MRI was established. Aging was associated with morphological changes in the pelvic floor muscles in both men and women. Geriatr Gerontol Int 2019; 19: 834-837.

Oncologic Outcome of Metastasectomy for Urothelial Carcinoma: Who Is the Best Candidate?

BACKGROUND

Resection of metastatic lesions (metastasectomy) is performed for highly selected patients with metastatic urothelial carcinoma (mUC). This study aimed to identify the clinicopathologic factors associated with oncologic outcome for patients who underwent metastasectomy for mUC.

METHODS

This analysis included 37 UC patients who underwent metastasectomy with curative intent at nine Japanese hospitals. The primary end point was cancer-specific survival. The Kaplan-Meier method with the log-rank test and the multivariable Cox proportional hazards model addressed the relationship between clinical characteristics and survival.

RESULTS

Metastasectomy was performed for pulmonary (n = 23), nodal (n = 7), and other (n = 7) metastases. The median survival time was 35.4 months (interquartile range [IQR] 15.5, not reached) from the detection of metastasis and 34.3 months (IQR 13.1, not reached) from metastasectomy. The 5-year cancer-specific survival rate after detection of metastasis was 39.7%. In the multivariate analysis, the time from primary surgery to detection of metastasis (time-to-recurrence [TTR]) of 15 months or longer (hazard ratio [HR] 0.23; p = 0.0063), no symptoms of recurrence (HR 0.23; p = 0.0126), and serum C-reactive protein (CRP) levels lower than than 0.5 mg/dl (HR 0.24; p = 0.0052) were significantly associated with better survival.

CONCLUSIONS

Long-term survival could be achieved for some patients with mUC who underwent metastasectomy. Lung and lymph nodes were predominant sites for metastasectomy. Symptoms, TTR, and CRP value were identified as associated with survival and should be taken into account when metastasectomy is considered.

Nomogram for predicting survival of postcystectomy recurrent urothelial carcinoma of the bladder

PURPOSE

We aimed to identify prognostic clinicopathological factors and to create a nomogram able to predict overall survival (OS) in recurrent urothelial carcinoma of the bladder (UCB) after radical cystectomy (RC).

MATERIALS AND METHODS

Among 1,087 patients with UCB who had undergone RC at our 11 institutions between 1990 and 2010, 306 patients who subsequently developed distant metastasis or local recurrence or both were identified. Clinical data were collected with medical record review. Univariate and multivariate Cox regression models addressed OS after recurrence. A nomogram predicting postrecurrence OS was constructed based on Cox proportional hazards model, without using postrecurrence factors (systemic chemotherapy and resection of metastasis). The performance of the nomogram was internally validated by assessing concordance index and calibration plots.

RESULTS

Of the 306 patients, 268 died during follow-up with a median survival of 7 months (95% CI: 5.8-8.5). Postrecurrence chemotherapy was administered in 119 patients (38.9%). Multivariable analysis identified 9 independent predictors for OS; period of time from RC to recurrence (time-to-recurrence), symptomatic recurrence, liver metastasis, hemoglobin level, serum alkaline phosphatase level, serum lactate dehydrogenase level, serum C-reactive protein level, postrecurrence chemotherapy, and resection of metastasis. A nomogram was formed with the following 5 variables to predict OS: time-to-recurrence, symptomatic recurrence, liver metastasis, albumin level, and alkaline phosphatase level. Concordance index rate was 0.75 (95% CI: 0.72-0.78) by internal validation using Bootstraps with 1,000 resamples. Calibration plots showed that the nomogram fitted well.

CONCLUSIONS

We identified 9 clinicopathological factors as independent OS predictors in postcystectomy recurrence of UCB. We also created a validated nomogram with 5 variables that efficiently stratified those patients regardless of eligibility for chemotherapy. The nomogram would be useful for acquiring relevant prognostic information and for stratifying patients for clinical trials.

Cancer-specific survival in patients with urothelial carcinoma of the bladder with recurrence after radical cystectomy: External validation of the prognostic risk stratification model

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Background: Prognosis of the patients with urothelial carcinoma of the bladder (UCB) who developed recurrence after radical cystectomy (RC) is generally poor, but can be variable. We previously showed that shorter time to recurrence (TTR) after RC, presence of symptoms on recurrence, more than one metastatic sites (organs), high serum C-reactive protein (CRP) level were associated with decreased survival in those patients, and proposed a model to stratify patients into 3 separate risk groups (Nakagawa et al. J Urol. 2013; 189:1275). The aim of this study was to evaluate the prognostic value of this model in a multi-institutional cohort of patients. Methods: We identified 267 patients who experienced disease recurrence after RC for UCB from 9 academic and community hospitals. Patients were categorized into three groups based on the presence of four risk factors, TTR of <1 year, presence of symptoms on recurrence, more than one metastatic sites (organs), and CRP level of ≥0.5 mg/dl: the favourable risk group included patients with none or one of these risk factors; the intermediate risk group with 2 risk factors; and those with 3 or 4 risk factors were assigned to the poor risk group. Results: Overall, median survival time (MST) of the entire cohort was 8.3 months (95%CI, 6.4-9.1). Two hundred and nineteen patients died of their disease with a median survival of 5.9 months. In a multivariate analysis, all of the 4 risk factors were statistically significant for the cancer-specific survival. Sixty-five (27.4%), 84 (35.4%), and 88 (37.1%) patients were in the favorable, intermediate and poor risk group, respectively. Thirty patients were excluded because CRP value was not obtained. MSTs of the patients in the favorable, intermediate and poor risk group were 22.2 (95% CI 16.1-28.3), 7.6 (95% CI 6.3-9.5), and 3.6 (95% CI 2.6-4.4) months, respectively, and the difference was statistically significant (p<0.001, log-rank test). Conclusions: We confirmed the prognostic value of our previous criteria based on the four variables in patients with recurrence after RC for UCB. This criteria would help in patient counseling and clinical trial design.