Risk factors of secondary cancer in laryngeal, oropharyngeal, or hypopharyngeal cancer after definitive therapy.

BACKGROUND: Our previous research showed that a high rate of secondary carcinogenesis is observed during follow-up after transoral surgery in patients with early-stage laryngeal, oropharyngeal, and hypopharyngeal cancers. We speculate that the contributing factors are alcohol drinking, smoking, and aging; however, we could not provide clear evidence. In this study, we aimed to identify the risk factors for secondary carcinogenesis in patients with these cancers, particularly factors associated with drinking and/or smoking. METHODS: The medical records of all-stage laryngeal, oropharyngeal, and hypopharyngeal cancer patients who had undergone definitive treatment were retrospectively analyzed. Assessments included visual and endoscopic observations of the primary site, enhanced cervical CT or US of the primary site and regional lymph nodes, PET-CT, and enhanced whole-body CT. Clinical characteristics were compared in patients with and without secondary carcinogenesis and in patients with hypopharyngeal cancer and patients with other cancers. RESULTS: Hypopharyngeal cancer was an independent risk factor for secondary cancer. The 5-year incidence rate of secondary cancer was 25.5%, 28.6%, and 41.2% in laryngeal, oropharyngeal, and hypopharyngeal cancers, respectively. Radiotherapy was defined as an independent risk factor in hypopharyngeal cancer patients with secondary cancers. No direct correlation was found between secondary carcinogenesis and alcohol consumption, smoking, or aging. CONCLUSIONS: Patients with hypopharyngeal cancer require close follow-up as they are at high risk of developing secondary cancer, possibly because out-of-field radiation exposure may induce systemic secondary carcinogenesis in hypopharyngeal cancer patients with genetic abnormality induced by alcohol consumption.

Clinical Practice Guidelines for tuberous sclerosis complex-associated renal angiomyolipoma by the Japanese Urological Association: Summary of the update.

New clinical issues have been raised through an interval of 7 years from the previous version (2016). In this study, we update the "Clinical Practice Guidelines for tuberous sclerosis complex-associated renal angiomyolipoma" as a 2023 version under guidance by the Japanese Urological Association. The present guidelines were cooperatively prepared by the Japanese Urological Association and Japanese Society of Tuberous Sclerosis Complex; committee members belonging to one of the two societies or specializing in the treatment of this disease were selected to prepare the guidelines in accordance with the "Guidance for preparing treatment guidelines" published by Minds (2020 version). The "Introduction" consisted of four sections, "Background Questions (BQ)" consisted of four sections, "Clinical Questions (CQ)" consisted of three sections, and "Future Questions (FQ)" consisted of three sections (total: 14 sections). Concerning CQ, an agreement was confirmed through voting by the committee members based on the direction and strength of recommendation, accuracy of evidence, and recommendation comments. The present guidelines were updated based on the current evidence. We hope that the guidelines will provide guiding principles for the treatment of tuberous sclerosis complex-associated renal angiomyolipoma to many urologists, becoming a foundation for subsequent updating.

A risk factor for newly diagnosed secondary cancer in patients with early-stage laryngeal, oropharyngeal, or hypopharyngeal cancer: sub-analysis of a prospective observation study.

BACKGROUND: We previously identified hypopharyngeal cancer as an independent risk factor for the incidence of newly diagnosed secondary cancers after the treatment of early-stage laryngeal, oropharyngeal, and hypopharyngeal cancers. We subsequently used a different patient cohort to validate the usefulness of this factor during the follow-up period in these patients. METHODS: Patients who underwent transoral surgery (TOS) as a definitive treatment between April 1, 2016, and September 30, 2020, were included. The incidence of secondary cancer was evaluated in hypopharyngeal and other cancers. Overall survival (OS), recurrence-free survival (RFS), and disease-free survival (DFS) outcomes were evaluated. Statistical analyses based on the risk factors were also performed. RESULTS: Incidence of new secondary cancer was 30% in hypopharyngeal cancer patients as compared to 11% in other cancer patients, and the risk was 3.60-fold (95% confidence interval 1.07-12.10) higher after definitive treatment for initial head and neck cancers. The 3-year OS, RFS, and DFS rates were 98%, 86%, and 67%, respectively. CONCLUSIONS: Among patients with early-stage laryngeal, oropharyngeal, and hypopharyngeal squamous cell carcinoma, who were initially treated with TOS, hypopharyngeal cancer patients had a higher risk of newly diagnosed secondary cancers as observed during the follow-up period.

Establishment of PDX-derived salivary adenoid cystic carcinoma cell lines using organoid culture method.

To generate a reliable preclinical model system exhibiting the molecular features of salivary adenoid cystic carcinoma (ACC) whose biology is still unclear due to the paucity of stable cell cultures. To develop new in vitro and in vivo models of ACC, the techniques of organoid culture and patient-derived tumor xenograft (PDX), which have attracted attention in other malignancies in recent years, were applied. Tumor specimens from surgically resected salivary ACC were proceeded for the preparation of PDX and organoid culture. The orthotopic transplantation of patient-derived or PDX-derived organoids was demonstrated into submandibular glands of NSG mice and those histology was evaluated. PDX-derived organoid cells were evaluated for the presence of MYB-mediated fusion genes and proceeded for in vitro drug sensitivity assay. Human ACC-derived organoids were successfully generated in three-dimensional culture and confirmed the ability of these cells to form tumors by orthotopic injection. Short-term organoid cell cultures from two individual ACC PDX tumors were also established that maintain the characteristic MYBL1 translocation and histological features of the original parent and PDX tumors. Finally, the establishment of drug sensitivity tests on these short-term cultured cells was confirmed using three different agents. This is the first to report an approach for the generation of human ACC-derived organoids as in vitro and in vivo cancer models, providing insights into understanding of the ACC biology and creating personalized therapy design for patients with ACC.

Efficacy and safety of low-dose everolimus treatment for renal angiomyolipoma associated with tuberous sclerosis complex.

BACKGROUND: The aim of this study was to evaluate the safety and efficacy of low-dose everolimus treatment in patients with tuberous sclerosis complex (TSC)-associated angiomyolipoma (AML) with renal dysfunction or low body weight. METHODS: We investigated a total of 50 adult patients underwent everolimus treatment for AML associated with TSC. For patients with renal dysfunction (serum creatinine level ≥ 1.5 mg/dl) or low body weight (body weight < 35 kg), 5 mg of everolimus was administered daily (low-dose group). For patients without renal dysfunction or low body weight, 10 mg of everolimus was administered daily (conventional-dose group). The treatment effects and adverse events were compared between the two groups. RESULTS: There were 20 patients in the low-dose group, and 30 in the conventional-dose group. The average reduction rate of the AML volume in the low-dose group was 52%, whereas it was 60% in the conventional-dose group. No significant differences were found in the average reduction rate between the groups (P = 0.24). The average blood everolimus trough levels were 7.7 ± 3.1 ng/mL in the low-dose group and 12.2 ± 5.7 ng/mL in the conventional-dose group. The level was significantly higher in the conventional-dose group than in the low-dose group (P = 0.004). The incidences of stomatitis and irregular menstruation were significantly lower in the low-dose group than in the conventional-dose group (P = 0.009, P = 0.045, respectively). CONCLUSIONS: The present study demonstrates that low-dose everolimus treatment is safe and effective for TSC-associated AML. This treatment was well tolerated and adverse events were mild in all cases.

The incidence of newly diagnosed secondary cancer; sub-analysis the prospective study of the second-look procedure for transoral surgery in patients with T1 and T2 head and neck cancer.

BACKGROUND: Our prospective study of patients with early T-stage head and neck cancer indicated a high incidence of newly diagnosed secondary malignancies during the follow-up period. We aimed to determine the incidence rate and risk factors of secondary malignancies in early-stage head and neck cancer patients. METHODS: We sub-analyzed the patient data of a previous study focusing on secondary cancer incidence. The endpoints were statistical analyses of risk factors and survival and incidence rates. RESULTS: The incidence rate of secondary cancer was 37%, the crude incidence of second primary cancers was 10.6 per 100 person-years, and the 5 year secondary cancer-free survival rate was 63%. The hypopharynx as the primary site was an independent significant predictive factor (odds ratio 3.96, 95% confidence interval 1.07-14.6, p = 0.039). CONCLUSIONS: Early stages of laryngeal, oropharyngeal, and hypopharyngeal cancer had a risk of secondary cancer, especially hypopharyngeal cancer. Attention to the secondary cancer has to be paid during the follow-up period after controlling the early-stage disease. These findings highlight the need for awareness of the incidence of secondary cancer in cases of early-stage primary head and neck cancer.

Validation of the risk factors for primary control of early T-stage laryngeal, oropharyngeal, and hypopharyngeal squamous cell carcinoma by transoral surgery: a prospective observational study.

BACKGROUND: We had previously identified the following risk factors for insufficient control of early T-stage head and neck cancer by transoral surgery (TOS): (1) tumor thickness > 7 mm on enhanced computed tomography (CT), and (2) poor differentiation in pathological examination. We subsequently used a different patient cohort to validate the usefulness of these factors in determining the need for adaptation of TOS. STUDY SETTING: A prospective observational study METHODS: Patients who received TOS as a definitive treatment between April 1, 2016 and September 30, 2020 were included. Primary control rates (by single TOS and TOS alone) in relation to the above-mentioned risk factors were calculated. Overall (O), recurrence-free (RF), and disease-free (DF) survival (S) outcomes were evaluated. A combination analysis based on the number of risk factors was also performed. RESULTS: Patients with tumor thickness > 7 mm had a 2.88-fold [95% confidence interval (CI) 1.01-8.51] higher risk of incomplete primary resection by single TOS, while patients who showed poor differentiation on pathological assessments had a 13.14-fold (95% CI 3.66-47.14) higher risk of insufficient primary control by TOS alone. The 3 year OS, RFS, and DFS rates were 99%, 83%, and 63%, respectively. Patients with both risk factors had a 93.00-fold (95% CI 4.99-1732.00) higher risk of incomplete primary control by TOS alone. CONCLUSIONS: Among patients with early-stage laryngeal, oropharyngeal, and hypopharyngeal squamous cell carcinoma, primary control by TOS alone may not be achieved in patients with both risk factors, that is, tumor thickness > 7 mm as measured by enhanced CT and poor differentiation on pathological examination.

Significant cases of central cusps, enamel pits, and oral fibromas in tuberous sclerosis complex.

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder in which benign nodular tumors form in the cerebral cortex, cerebellum, and throughout the body causing various symptoms. In this study, we summarized the incidence of dental findings in patients with TSC at our hospital and its association with diseases in various organs. Patients diagnosed with TSC at our hospital between January 2013 and September 2017, and who were examined in the dental and oral surgery department were included in this study. The presence of intraoral manifestations (central cusps, enamel pits, oral fibromas) was examined by means of visual inspection, intraoral photography, and X-ray photography. In addition, the relationship with associated diseases (neurological, cutaneous, cardiac, renal, and pulmonary) according to organ and disease severity was examined. The mean age (± SD) of the 42 TSC patients (19 men and 23 women) was 27.8 ± 14.6 years, of which 24 patients (11 men and 13 women) presented with oral manifestations. Of these patients, seven had central cusps, 10 had enamel pits, and 17 had oral fibromas. The group with central cusps had significantly higher neurological issues in the relationship between intraoral manifestations and associated disease based on the involved organ. The prevalence of central cusps in TSC was 16.7%, which is significantly higher than the 2.6% reported in healthy Japanese subjects. The central cusp is a diagnostic factor alongside the presence of enamel pits and oral fibromas, which can aid in the early diagnosis of TSC by dentists.

Values of alkaline phosphatase at the diagnosis of castration resistance and response to primary androgen deprivation therapy as predictors of subsequent metastasis in non-metastatic castration-resistant prostate cancer.

PURPOSE: Among various therapeutic options available for metastatic castration-resistant prostate cancer (mCRPC), only apalutamide and enzalutamide have shown evidences of improved metastasis-free survival (MFS) for non-metastatic castration-resistant prostate cancer (nmCRPC). However, there is a paucity of evidence to indicate who may be targeted for aggressive therapy among patients with nmCRPC. The objectives of this retrospective study were to explore predictors of metastasis in patients with nmCRPC and to identify a subpopulation of patients with nmCRPC who may benefit from aggressive therapy. METHODS: A total of 115 patients with CRPC who had no metastasis detected at the time of diagnosis of CRPC were included in this retrospective study. All patients were treated at Jikei University and its affiliated hospitals. The primary outcome measure was MFS from the time of diagnosis of CRPC. Predictors of MFS were also explored with a multivariate Cox hazard model. RESULTS: The median observation period after diagnosis of CRPC was 30 months (range 2-143 months). Kaplan-Meier analysis revealed a median MFS of 76. Multivariate analysis demonstrated that low alkaline phosphatase (ALP) values at diagnosis of CRPC and favorable response to primary androgen deprivation therapy (ADT) were significant predictors of longer MFS (P = 0.011, and 0.031, respectively). CONCLUSIONS: Results of this study suggest that high ALP values at diagnosis of CRPC and poor response to primary ADT may predict the propensity of metastasis in patients with nmCRPC. Further prospective studies will be required enrolling more patients to confirm our findings.

Hyperprogression after pembrolizumab treatment in two patients with metastatic urothelial carcinoma.

Hyperprogression has recently been recognized as a new pattern of progression in patients undergoing immune checkpoint inhibitor treatment. Here, we report two cases that showed hyperprogression during the initial phase of pembrolizumab treatment for metastatic urothelial carcinoma. The first patient, who received pembrolizumab as a second-line treatment, developed severe respiratory failure due to the rapid progression of lung metastases on the ninth day after the third pembrolizumab treatment. The second patient developed jaundice and hepatic dysfunction due to the progression of a metastatic lymph node of the liver hilum after the first administration of pembrolizumab. She developed multiple brain metastases with intraventricular bleeding on the 10th day after the second administration of pembrolizumab. It is important to be aware that hyperprogression sometimes occurs quite a while after starting treatment, and that both pseudoprogression and hyperprogression may occur in the early stage of treatment.

Effect of everolimus treatment for renal angiomyolipoma associated with tuberous sclerosis complex: an evaluation based on tumor density.

BACKGROUND: The aim of this study was to evaluate the influence of components of angiomyolipoma (AML) on the efficacy of everolimus. METHODS: We investigated a total of 40 patients with tuberous sclerosis complex (TSC) who had AML ≥4 cm in diameter. The components of the AML were determined using abdominal computed tomography (CT) images. The AML density was measured as the mean Hounsfield unit (HU) values of the whole area of the AML on axial CT images. We classified them into two groups, i.e., a lipid group with a predominant lipid component (HU ≤ -50) and a solid group with predominant vascular and muscle components (HU ≥30). For each patient, we measured the AML reduction rate and transition of the mean HU value. RESULTS: The mean reduction rate of AML in the lipid group was 24%, whereas it was 68% in the solid group (P < 0.001). The mean tumor density after 6 months was decreased in both groups. In particular, the density significantly decreased compared to the baseline in the solid group (P < 0.001). The tumor density did not change after 6 months in either group. CONCLUSION: The effect of everolimus on TSC-AML is mainly a reduction of the solid components consisting of angioma and leiomyoma. The tumor density at the start of treatment might be a predictive marker for the response to everolimus in TSC-AML.

Effect of everolimus treatment for regrown renal angiomyolipoma associated with tuberous sclerosis complex after transcatheter arterial embolization.

BACKGROUND: The aim of this study was to evaluate the effects and the utility of second-line everolimus treatment for regrown renal angiomyolipoma (AML) with tuberous sclerosis complex (TSC) after transcatheter arterial embolization (TAE). METHODS: We investigated a total of 14 patients who underwent second-line everolimus treatment for TSC-AML that regrew after TAE, and assessed their effects and adverse events. Everolimus treatment was performed for AML with a maximum diameter of 4 cm. To determine the reduction ratio of AML, the volume of AML was measured using multislice helical computed tomography. Adverse events were evaluated according to CTCAE v4.0-JCOG. We further compared the treatment effect and adverse events with those in patients receiving first-line everolimus treatment. RESULTS: The AML volume decreased in all patients, with a ≥ 50% volume decrease in 57% (8 of 14) of the cases, and the mean reduction rate was 53%. We observed no significant difference in the mean reduction rate of AML between second-line everolimus treatment for regrown TSC-AML after TAE and first-line everolimus treatment for TSC-AML. The adverse events were mild and consistent with those reported in our previous study. CONCLUSION: Although further studies are needed, everolimus appears to be effective as second-line treatment for TSC-AML that regrew after TAE and a beneficial treatment option for TSC-AML.

Identification of human papillomavirus (HPV) 16 DNA integration and the ensuing patterns of methylation in HPV-associated head and neck squamous cell carcinoma cell lines.

Recent studies showed that human papillomavirus (HPV) integration contributes to the genomic instability seen in HPV-associated head and neck squamous cell carcinoma (HPV-HNSCC). However, the epigenetic alterations induced after HPV integration remains unclear. To identify the molecular details of HPV16 DNA integration and the ensuing patterns of methylation in HNSCC, we performed next-generation sequencing using a target-enrichment method for the effective identification of HPV16 integration breakpoints as well as the characterization of genomic sequences adjacent to HPV16 integration breakpoints with three HPV16-related HNSCC cell lines. The DNA methylation levels of the integrated HPV16 genome and that of the adjacent human genome were also analyzed by bisulfite pyrosequencing. We found various integration loci, including novel integration sites. Integration loci were located predominantly in the intergenic region, with a significant enrichment of the microhomologous sequences between the human and HPV16 genomes at the integration breakpoints. Furthermore, various levels of methylation within both the human genome and the integrated HPV genome at the integration breakpoints in each integrant were observed. Allele-specific methylation analysis suggested that the HPV16 integrants remained hypomethylated when the flanking host genome was hypomethylated. After integration into highly methylated human genome regions, however, the HPV16 DNA became methylated. In conclusion, we found novel integration sites and methylation patterns in HPV-HNSCC using our unique method. These findings may provide insights into understanding of viral integration mechanism and virus-associated carcinogenesis of HPV-HNSCC.

Intermittent everolimus administration for renal angiomyolipoma associated with tuberous sclerosis complex.

OBJECTIVES: To evaluate the effects and utility of intermittent everolimus treatment for renal angiomyolipoma associated with tuberous sclerosis complex. METHODS: We investigated a total of 26 patients with tuberous sclerosis complex who had angiomyolipoma ≥4 cm in diameter. For each patient, we analyzed the reduction in the size of the angiomyolipoma, the change in size after everolimus withdrawal, the size reduction rate on everolimus readministration and adverse events caused by everolimus. The volume of angiomyolipoma was measured using abdominal computed tomography or magnetic resonance imaging. Adverse events were evaluated according to CTCAE v4.0-JCOG. RESULTS: The average size reduction rate of angiomyolipoma in the initial treatment with everolimus was 67%. Eight patients (31%) did not have enlarged angiomyolipoma after everolimus withdrawal. The other 18 patients (69%) restarted everolimus treatment because of enlargement of the angiomyolipoma. The average size reduction rate of angiomyolipoma in the everolimus retreatment group was 61%, which was equivalent to the rate for the initial treatment. There were fewer adverse events during everolimus retreatment than in the initial treatment. CONCLUSIONS: This is the first report regarding intermittent everolimus treatment for renal angiomyolipoma associated with tuberous sclerosis complex. This treatment is effective for tumor control and adverse event management. This beneficial treatment option for patients can minimize the drug dosage and the occurrence of adverse events.

Outcomes of everolimus treatment for renal angiomyolipoma associated with tuberous sclerosis complex: A single institution experience in Japan.

OBJECTIVES: To evaluate the efficacy and toxicity profiles of everolimus in Japanese patients with renal angiomyolipoma associated with tuberous sclerosis complex. METHODS: Patients with a 4-cm or larger angiomyolipoma meeting the diagnostic criteria of tuberous sclerosis complex were selected as participants of our investigation. In each case, we assessed tuberous sclerosis complex-associated symptoms, the treatment effect and adverse events. The treatment effect was evaluated by measuring the tumor volume reduction rate using abdominal computed tomography or magneitc resonance imaging. Adverse events were investigated using CTCAE v4.0-JCOG. The dose of everolimus was set at 10 mg once a day for adults. For childhood angiomyolipoma, everolimus administration was initiated at a dose of 5 mg once a day. Blood everolimus level was measured, and the dose was adjusted to maintain this within a range of 5-15 ng/mL. RESULTS: The angiomyolipoma volume decreased in 46 of 47 cases, and the mean reduction rate for all cases was 60% in 12 months. The angiomyolipoma volume markedly decreased in the first 3 months, and the size leveled off after 6 months. The main adverse events related to everolimus treatment were stomatitis (91%) and irregular menstruation (65%). Grade 3 or severer adverse events were noted in three cases (6%). All patients developed some adverse events in the first 6 months. The incidence markedly decreased to 40-50% after 13 months. CONCLUSION: The tumor volume-reducing effect of everolimus in a Japanese population was equivalent to or higher than that in Western populations. A wide variety of everolimus treatment-related adverse events can be observed, but most cases are very mild. Special attention should be given to stomatitis, irregular menstruation and interstitial lung disease as adverse events.

Clinical efficacy and prognostic factors of tumor progression in Japanese patients with advanced renal cell carcinoma treated with sorafenib.

OBJECTIVE: Result of clinical trial for registration purpose is often difficult to generalize because of its limited population in number and inclusion criteria. METHODS: To understand the efficacy of sorafenib under daily medical practice, we retrospectively investigated therapeutic outcomes of 175 Japanese patients with advanced renal cell carcinoma treated with sorafenib at 15 centers. RESULTS: The objective response rate and disease control rate were 15.4 and 77.1%, respectively, being similar to those in the Phase II study in Japanese patients (19.4 and 73.6 months). Any tumor shrinkage was observed with 53% of patients, while tumor control without growth was in 61%. Lung lesions were more sensitive to sorafenib than other lesions, in terms of any tumor shrinkage (54%) and the extent of maximal shrinkage, while tumor control was better in lymph node metastases (77%) than in lung (69%). Liver was worse in any tumor shrinkage (35%), tumor control (55%) and the extent of tumor growth. Slightly, shorter median overall survival of 21.1 months compared with Phase II clinical trial (25.3 months) is likely to be attributable to different patient population, because median overall survival was improved to 26.4 months when the population was matched to that in Phase II trial. Univariate and multivariate analyses identified prognostic factors for worse overall survival, including intermediate and poor Memorial Sloan-Kettering Cancer Center risk, Eastern Cooperative Oncology Group performance status ≥1, the presence of non-clear cell component and the presence of liver metastasis. CONCLUSIONS: In conclusion, the present study confirmed the efficacy of sorafenib in the real-world setting on advanced renal cell carcinoma.

[Six cases of renal collecting duct carcinoma].

We treated 6 patients with renal collecting duct carcinoma (CDC) in our hospital from December 2004 to December 2011. We compared clinico-pathological findings among all patients. The median age was 58 years (range, 37-77 years). Hematuria, back pain, and fatigue were observed in 5 patients with CDC. Five patients were pathologically diagnosed by radical nephrectomy while a patient was diagnosed by percutaneous renal biopsy without radical nephrectomy. Lymph node metastasis and distant metastasis were observed at diagnosis in 3 and 2 patients, respectively. Five of the 6 patients received systemic therapy after surgery, cytokine therapy in 2 patients, systemic chemotherapy in a patient, and molecular-targeting therapy in 2 patients, respectively. The median overall survival was 15 months (range, 1-44 months). Overall, the 1- and 3-year survival rates were 67 and 33%, respectively. Most of the patients had symptomatic advanced disease at diagnosis. Even though nephrectomy was performed, systemic treatment was not effective in such patients.

[A case of papillary renal cell carcinoma type 2 resistant to sunitinib responded to second line therapy with axitinib].

According to previous studies, papillary renal cell carcinoma (pRCC) type 2 is known to have a poor prognosis, especially in cases with metastases. We report a case of pRCC that responded well to axitinib administered as second line therapy. The patient was a 52-year-old woman who presented at our hospital with an incidental tumor on the left kidney. She underwent laparoscopic radical nephrectomy, and the pathological diagnosis was pRCC type 2, grade 3 pT1b. Multiple lung and bone metastases were observed following the four months, and histological findings of lung metastases was metastatic RCC. Although sunitinib was administered as first line therapy, tumor progression was observed after the first cycle of treatment. Therefore, axitinib (10 mg/day) was administrated as second-line therapy and was gradually increased to 14 mg/day. Five months after the administration of axitinib, the maximum tumor diameter of the lung metastases reduced by 83%. At present, eight months have passed since the start of axtinib administration, but the response was still maintained and the adverse events were generally tolerable.

Shrinkage of prostate volume in sunitinib-treated patients with renal cell carcinoma.

Sunitinib is widely used to treat patients with advanced renal cell carcinoma; however, its influences on the prostate volume and lower urinary tract symptoms remain unclear. To investigate the influence of sunitinib on clinical findings of urinary tract, we recruited a total of 20 male patients with advanced renal cell carcinoma who are treated with sunitinib. We evaluated clinical findings during clinical visits over 24 weeks: International Prostate Symptom Score, urine flow rate, residual urine volume, serum prostate-specific antigen level and prostate volume. Residual urine and prostate volumes were significantly decreased at Week 24. The residual urine volume was especially decreased in patients with a high residual volume at baseline. No differences were observed in the International Prostate Symptom Score total score, International Prostate Symptom Score quality of life score, maximal urinary flow rate or prostate-specific antigen level. We observed a reduction in prostate volume and an improvement in urinary symptoms through relief from urinary tract obstruction during sunitinib treatment. Careful attention to urinary functions and drug dose adjustment seems to be necessary in patients with comorbid benign prostatic hyperplasia or dysuria.