Accumulation of cellular prion protein within β-amyloid oligomer plaques in aged human brains

Alzheimer’s disease (AD) is the main cause of dementia, and β‐amyloid (Aβ) is a central factor in the initiation and progression of the disease. Different forms of Aβ have been identified as monomers, oligomers, and amyloid fibrils. Many proteins have been implicated as putative receptors of respective forms of Aβ. Distinct forms of Aβ oligomers are considered to be neurotoxic species that trigger the pathophysiology of AD. It was reported that cellular prion protein (PrP^C) is one of the most selective and high‐affinity binding partners of Aβ oligomers. The interaction of Aβ oligomers with PrP^C is important to synaptic dysfunction and loss. The binding of Aβ oligomers to PrP^C has mostly been studied with synthetic peptides, cell culture, and murine models of AD by biochemical and biological methods. However, the molecular mechanisms underlying the relationship between Aβ oligomers and PrP^C remain unclear, especially in the human brain. We immunohistochemically investigated the relationship between Aβ oligomers and PrP^C in human brain tissue with and without amyloid pathology. We histologically demonstrate that PrP^C accumulates with aging in human brain tissue even prior to AD mainly within diffuse‐type amyloid plaques, which are composed of more soluble Aβ oligomers without stacked β‐sheet fibril structures. Our results suggest that PrP^C accumulating plaques are associated with more soluble Aβ oligomers, and appear even prior to AD. The investigation of PrP^C accumulating plaques may provide new insights into AD.

Ruptured mediastinal mature teratoma causing severe mediastinitis: report of a surgically resected case and a literature review

Background

Mediastinal teratomas occasionally rupture into the thoracic cavity, which induces mediastinitis or various other severe complications. Surgical treatment is crucial for ruptured teratomas; however, few literature reviews to date have addressed the characteristics of ruptured mediastinal teratomas.

Case presentation

We report a 29-year-old woman with severe mediastinitis owing to a mediastinal mature teratoma that ruptured into the mediastinum and right pleural cavity. Surgical resection by median sternotomy was performed within 24 hours after emergency admission. Intraoperative findings demonstrated the ruptured wall of the tumor with exposure of its white contents, which appeared similar to skin and fat, and necrotic tissue in the anterior mediastinum. The tumor was adhered to the right upper lobe, the ascending aorta, and pericardium. Owing to the severe adhesion of the tumor caused by inflammation in the surrounding tissues, a small portion of the tumor could not be removed, and hence complete resection with a sufficient surgical margin was not achieved. Pathologically, the tumor consisted of a solid mass and a cystic mass with severe adhesion to the resected portion of the lung, which included skin and lipid tissue. The tumor was concluded to be a mature teratoma as neither an immature component nor malignant transformation was observed. The patient had an uneventful postoperative course.

Conclusions

To our knowledge, this is the report of successful surgical resection of a ruptured mediastinal teratoma causing severe mediastinitis, with the first literature review of ruptured mediastinal teratomas. We also discuss relevant findings from reports in the literature.

Pathological evaluation of tumor grade for salivary adenoid cystic carcinoma: A proposal of an objective grading system

Three pathological grading systems advocated by Perzin/Szanto, Spiro, and van Weert are currently used for adenoid cystic carcinoma (AdCC). In these systems, the amount or presence of the solid tumor component in AdCC specimens is an important index. However, the “solid tumor component” has not been well defined. Salivary AdCC cases (N = 195) were collected after a central pathology review. We introduced a novel criterion for solid tumor component, minAmax (minor axis maximum). The largest solid tumor nest in each AdCC case was histologically screened, the maximum oval fitting the solid nest was estimated, and the length of the minor axis of the oval (minAmax) was measured. The prognostic cutoff for the minAmax was determined using training and validation cohorts. All cases were evaluated for the four grading systems, and their prognostic impact and interobserver variability were examined. The cutoff value for the minAmax was set at 0.20 mm. Multivariate prognostic analyses showed the minAmax and van Weert systems to be independent prognostic tools for overall, disease‐free, and distant metastasis‐free survival while the Perzin/Szanto and Spiro systems were selected for overall survival but not for disease‐free or distant metastasis‐free survival. The highest hazard ratio for overall survival (11.9) was obtained with the minAmax system. The reproducibility of the minAmax system (kappa coefficient of 0.81) was scored as very good while those of the other three systems were scored as moderate. In conclusion, the minAmax is a simple, objective, and highly reproducible grading system useful for prognostic stratification for salivary AdCC.

Epithelial-Myoepithelial Carcinoma

Epithelial-myoepithelial carcinoma is an uncommon low-grade salivary gland carcinoma. It is classically characterized by biphasic tubular structures composed of inner eosinophilic ductal cells and outer clear myoepithelial cells. In addition, epithelial-myoepithelial carcinoma sometimes shows various histologic features, including a cribriform pattern, basaloid appearance, and sebaceous differentiation. Because clear myoepithelial cells are also noted in other benign and malignant salivary gland tumors, the histologic variety and similarity with other tumor entities make the diagnosis of epithelial-myoepithelial carcinoma challenging. A recent analysis revealed that HRAS hotspot point mutations are specifically identified in epithelial-myoepithelial carcinoma and the assessment of given genes facilitate the correct diagnosis.

A Rare Case of Ectopic Adrenocorticotropic Hormone Syndrome with Recurrent Olfactory Neuroblastoma

A 40-year-old woman who had a history of recurrent olfactory neuroblastoma presented with full moon face, central obesity, buffalo hump, impaired glucose tolerance and bilateral cervical lymph node swelling. Laboratory tests showed morbidly elevated levels of adrenocorticotropic hormone (ACTH) and cortisol, which were not suppressed by high-dose (8 mg) dexamethasone. Biopsies of the enlarged cervical lymph nodes revealed ACTH-positive metastatic olfactory neuroblastoma, and ectopic ACTH syndrome was diagnosed. Metyrapone was used to suppress cortisol production and resulted in decreased levels of ACTH and cortisol. Bilateral cervical tumor resection further reduced the ACTH and cortisol levels, accompanied by a reduction in the metyrapone dosage. Cushing's syndrome was alleviated through ACTH-producing tumor removal.

Salvage carbon ion radiotherapy for recurrent solitary fibrous tumor: A case report and literature review

BACKGROUND

Malignant solitary fibrous tumor (MSFT) arising from the spinal cord is extremely rare and poorly understood mesenchymal neoplasms: only a few MSFT in the spinal canal has been described. We describe the clinical course of the patient with MSFT arising from the thoracic spinal cord.

CASE REPORT

We describe the clinical course of the patient and the radiological and pathological findings of the tumor. The tumor had been resected by microscopic posterior approach and video-assisted thoracic surgery, but local recurrence was observed by MRI at 1-year follow-up period. No metastatic lesion was confirmed. Then, carbon ion radiotherapy (CIRT) was administered to the recurrent lesion. Local suppression has been observed for 40 months after irradiation.

CONCLUSION

Dumbbell-shaped MSFT arising from thoracic spinal cord is a highly unusual presentation. CIRT might be effective for treatment of recurrent tumors.

Diffusion-weighted imaging might be useful for reactive lymphoid hyperplasia diagnosis of the liver: A case report

BACKGROUND

Reactive lymphoid hyperplasia (RLH) of the liver is a rare liver lesion. It is considered difficult to differentiate radiologically from hepatocellular carcinoma, metastatic liver tumor and other pathologies.

CASE SUMMARY

A 54-year-old woman presented to our hospital with RLH of the liver. The patient had a diagnosis of metastatic carcinoma of the liver from an unknown origin and subsequently underwent partial hepatectomy. However, histopathological analysis revealed RLH. The lesion showed perinodular enhancement in the arterial phase on contrast-enhanced computed tomography and magnetic resonance imaging. On diffusion-weighted imaging (DWI), we encountered linear hyperintensity along the portal tract consecutive to the liver lesion, which is a new characteristic radiologic finding. This finding corresponded to the lymphoid cell infiltration of the portal tract. Furthermore, there was strongly restricted diffusion on the apparent diffusion coefficient map. We used these characteristic radiologic findings to diagnose the lesion as a lymphoproliferative disease.

CONCLUSION

The linear hyperintensity consecutive to the liver lesion on DWI provided additional valuable diagnostic information.

Prognostic impact of CRTC1/3-MAML2 fusions in salivary gland mucoepidermoid carcinoma: A multiinstitutional retrospective study

Mucoepidermoid carcinoma (MEC) is rare, but the most common primary malignancy of the salivary gland and not infrequent in young individuals. CRTC1/3-MAML2 fusions are frequently detected in MEC and are useful as a diagnostic biomarker. However, there has been debate as to whether the fusions have prognostic significance. In this study, we retrospectively collected 153 salivary gland MEC cases from 11 tertiary hospitals in Japan. As inclusion criteria, the MEC patients in this study had curative surgery as the initial treatment, received no preoperative treatment, and had no distant metastasis at the time of the initial surgery. The MEC diagnosis was validated by a central pathology review by five expert salivary gland pathologists. The CRTC1/3-MAML2 fusions were detected using FISH and RT-PCR. In 153 MEC cases, 90 (58.8%) were positive for CRTC1/3-MAML2 fusions. During the follow-up period, 28 (18.3%) patients showed tumor recurrence and 12 (7.8%) patients died. The presence of the fusions was associated with favorable tumor features. Of note, none of the fusion-positive patients died during the follow-up period. Statistical analysis showed that the presence of the fusions was a prognostic indicator of a better overall survival in the total and advanced-stage MEC cohorts, but not in the early-stage MEC cohort. In conclusion, CRTC1/3-MAML2 fusions are an excellent biomarker for favorable overall survival of patients with salivary gland MEC.

Multicentre, retrospective study of the efficacy and safety of nivolumab for recurrent and metastatic salivary gland carcinoma

Although immune-checkpoint inhibitors (ICIs) are effective against various cancers, little is known regarding their role in salivary gland carcinoma (SGC) treatment. Therefore, we evaluated the efficacy and safety of nivolumab monotherapy in patients with recurrent and/or metastatic SGC. In this multicentre retrospective study, nivolumab (240 mg) was administered every 2 weeks. The overall response rate (ORR), progression-free survival (PFS), overall survival (OS), and safety were examined; the correlation between treatment outcomes and clinicopathological factors was analysed. Twenty-four patients were enrolled; the most common histopathology was salivary duct carcinoma. Eleven tumours were PD-L1-positive; no tumour was microsatellite instability-high. The ORR was 4.2%, and the median PFS and OS were 1.6 and 10.7 months, respectively. One patient continued nivolumab for 28 months without disease progression. One patient showed grade 4 increase in creatine phosphokinase levels and grade 3 myositis. Biomarker analysis revealed significantly increased OS in patients with performance status of 0; modified Glasgow prognostic score of 0; low neutrophil-to-lymphocyte ratio, lactate dehydrogenase, and C-reactive protein; and high lymphocyte-to-monocyte ratio and in patients who received systemic therapy following nivolumab. Although nivolumab's efficacy against SGC was limited, some patients achieved long-term disease control. Further studies are warranted on ICI use for SGC.

Salivary duct carcinoma: Updates in histology, cytology, molecular biology, and treatment

Salivary duct carcinoma (SDC) is an aggressive subtype of primary salivary gland carcinoma, often with an advanced stage at presentation and high rates of metastasis and recurrence. It most commonly arises in the parotid gland of older men and microscopically resembles high-grade breast ductal carcinoma. While 50 years have lapsed since the first report of this entity, recent intensive studies have shed light on its biologic, genetic, and clinical characteristics. The diagnosis of SDC is aided by the immunohistochemical expression of androgen receptor (AR) coupled with its characteristic histomorphology. Fine-needle aspiration typically reveals cytologic features of high-grade carcinoma, and ancillary studies using cell block material can facilitate the specific diagnosis of SDC. In surgical specimens, certain histologic features are important prognostic factors, including nuclear pleomorphism, mitotic counts, vascular invasion, and the morphology at the invasion front. Several clinical studies have shown promising results using targeted therapy for AR and human epidermal growth factor receptor 2 (HER2), and the latest version of the National Comprehensive Cancer Network guidelines recommends the evaluation of AR and HER2 status before treatment. Recent molecular analyses have revealed multiple heterogeneous alterations in well-known oncogenes and tumor suppressor genes, including TP53, HRAS, PIK3CA, PTEN, and BRAF. Clinical trials of drugs targeting these genes may broaden the treatment options for SDC in the near future.

Microsecretory adenocarcinoma of the hard palate: A case report of a recently described entity

We report a case of microsecretory adenocarcinoma of the hard palate. The patient is a 37-year-old woman with a 15 mm submucosal tumor, which was incidentally found by her primary care dentist, in her hard palate. Preoperative magnetic resonance imaging revealed a tumor exhibiting high signal on T2-weighted image, which was gradually enhanced on dynamic study. Histologically, the tumor border was ill-defined without fibrous capsule and adjoined minor salivary gland with permeative infiltration at the tumor periphery. The tumor comprised intercalated duct-like cells with polygonal narrow eosinophilic to clear cytoplasm and small, uniform oval nuclei. These cells formed small infiltrative microcysts, tubules and fascicular cords collecting pale basophilic secretions and small vacuoles setting in an abundant fibromyxoid stroma. The tumor cells were positive for CK AE1+AE3, S-100 protein, and p63, while are completely negative for p40, alpha-SMA, and calponin. The MEF2C-SS18 fusion was identified by reverse transcriptase-polymerase chain reaction followed by Sanger sequencing. The combination of characteristic histology, immunophenotype, and presence of MEF2C-SS18 fusion indicated the diagnosis of microsecretory adenocarcinoma of the hard palate, an entity described only recently. Post-operative course was uneventful and there was no evidence of disease at 4 months after surgery.

The impact of clinicopathological factors on clinical outcomes in patients with salivary gland adenoid cystic carcinoma: a multi-institutional analysis in Japan

BACKGROUND

Owing to the low incidence of adenoid cystic carcinoma (AdCC), reliable survival estimates and prognostic factors remained unclarified.

METHODS

In this multi-institutional retrospective analysis, we collected 192 AdCC cases, and investigated the impact of clinicopathological factors on clinical outcomes of the patients. All AdCC cases were of salivary gland origin and were surgically treated with curative intent. Diagnoses of AdCC were validated by a central pathology review by expert pathologists.

RESULTS

The 5-year overall survival (OS) and disease-free survival (DFS) rates were 92.5 and 50.0%, respectively. Treatment failure occurred in 89 patients (46%) with the distant failures in 65 (34%). Multivariate analysis indicated that pN2 and a pathologically positive surgical margin were independent prognostic factors for both OS and DFS. Histological grade III was an independent prognostic factor for OS. A primary site in the submandibular gland, pT3/4, pN1, and histological grade II were independent prognostic factors for DFS. Postoperative radiation therapy (PORT) improved the locoregional control (LRC) rate. Prophylactic neck dissection was not associated with a better OS or better LRC among patients with cN0. Facial nerve dissection did not improve clinical outcomes in parotid AdCC cases without facial nerve palsy.

CONCLUSIONS

A higher TN classification, a pathologically positive surgical margin, and a higher histological grade were associated with a lower OS. PORT improved LRC rates but neck dissection failed to improve clinical outcomes in patients with cN0. As the distant metastasis was frequent, effective systemic therapy is imperative to improve the survival of AdCC patients.

A Familial Case of a Whole Germline CDC73 Deletion Discordant for Primary Hyperparathyroidism

INTRODUCTION

Primary hyperparathyroidism (PHPT) occurs as part of familial syndromes, including CDC73-related disorders caused by germline pathogenic variants of the CDC73 gene, particularly in early adulthood. Herein, we report a familial case of a whole germline CDC73 deletion discordant for PHPT.

CASE DESCRIPTION

A 15-year-old boy was admitted to our hospital because of persistent nausea and vomiting. Laboratory tests showed hypercalcemia (13.6 mg/dL), hypophosphatemia (2.4 mg/dL), and elevated intact PTH level (149 pg/mL). Imaging studies showed an enlarged single parathyroid gland. Thus, the diagnosis of PHPT was made. Microarray analysis of peripheral blood DNA showed a 3.4-Mb heterozygous deletion of 1q31 encompassing 11 genes, including CDC73. Total thyroidectomy/parathyroidectomy was performed; histology was compatible with parathyroid adenoma without any evidence of malignancy. DNA sequencing of the removed adenoma confirmed a hemizygous nonsense variant in the CDC73 gene in a mosaic manner, which was potentially involved in parathyroid tumorigenesis as the "second hit." Importantly, the same deletion was identified in his 52-year-old father who had an unremarkable medical history.

CONCLUSIONS

These data clearly demonstrate the Knudson two-hit theory from a molecular viewpoint. Phenotypic variability and incomplete penetrance of CDC73-related disorders, even if caused by a gross deletion, should be noted in a clinical setting.

Cytology Reporting System for Lung Cancer from the Japan Lung Cancer Society and Japanese Society of Clinical Cytology: An Interobserver Reproducibility Study and Risk of Malignancy Evaluation on Cytology Specimens

INTRODUCTION

The classification of lung carcinoma is based on small biopsies and/or cytology in 80% of patients with non-small cell carcinoma. However, there is no widely accepted classification system for respiratory cytology. The Japan Lung Cancer Society (JLCS) and Japanese Society of Clinical Cytology (JSCC) have proposed a new four-tiered cytology reporting system for lung carcinoma with the following categories: (1) "negative for malignancy," (2) "atypical cells," (3) "suspicious for malignancy," and (4) "malignancy."

OBJECTIVE

The aim of this work was to perform an interobserver reproducibility study to confirm the utility of the four-tiered reporting system on respiratory cytological samples.

METHODS

We analyzed 90 cytological samples obtained with bronchoscopy. Seven observers classified these cases into each category by reviewing one Papanicolaou-stained slide per case according to the three-, four-, and five-tiered reporting systems.

RESULTS

The interobserver agreement was fair in the three- (κ = 0.50), four- (κ = 0.45), and five-tiered (κ = 0.45) reporting systems. However, the four-tiered reporting system provided more precise information than the three-tiered reporting system in patient management. The risk of malignancy in the four-tiered reporting system was also stratified well: 19.3% for "negative for malignancy," 45.6% for "atypical cells," 74.7% for "suspicious for malignancy," and 88.1% for "malignancy."

CONCLUSIONS

The reporting system proposed by the JLCS and JSCC was designed to enhance the communication between clinicians and pathologists and among different institutions. It is simple and applicable to cytological diagnosis of any respiratory diseases. We propose establishing an international classification for respiratory cytology, harmonizing the reporting systems proposed by different countries.

Neck dissection prolongs survival in patient with stage IVC hypopharyngeal carcinoma with mixed responses to nivolumab

Surgical intervention aids in maintaining quality of life in patients with recurrent metastatic head and neck carcinoma with mixed responses to nivolumab treatment. However, the mechanisms involved in these mixed responses remain unclear. Systemic chemotherapy using the EXTREME regimen was administered to the patient with hypopharyngeal carcinoma and liver metastases as well as cervical lymph node metastases. The patient was subsequently treated with nivolumab after developing signs of progressive disease. Although the hypopharyngeal tumors and liver metastases were well-controlled, cervical lymph node dissection was performed because of the enlargement of some of the lymph node metastases. Postoperative nivolumab administration was resumed, and this patient is presently alive and disease-free. Immediately after neck dissection, the LNs that responded and those that did not respond to nivolumab were separated and evaluated. The LNs that responded well to nivolumab presented with prominent interstitial fibrosis. Conversely, in LNs that enlarged after nivolumab, significant proliferation of the viable tumor cells and almost no degeneration or necrosis was observed. Additionally, we performed immunohistological assessments on pathologic samples of multiple lesions with differing responses to treatment. Targeted surgical intervention appears to be a valuable adjunct to treatment with nivolumab.

Giant cell arteritis in a patient with aortic dissection: a case report

Aortic lesions, such as an aortic aneurysm, are known as a late complication that usually occurs several years after the onset of giant cell arteritis. Here, we report a rare case of large-vessel giant cell arteritis in a patient with aortic dissection. A 71-year-old man presented with acute back pain and was diagnosed with aortic dissection, Stanford type A, and he underwent elective ascending aortic replacement. Further studies showed that the resected ascending aorta had aortic dissection and multinucleated giant cell granulomas; the granulomas were located in the media near the intima with partial destruction of the internal elastic lamina; there was no stenosis of the feeding blood vessel or fibrosis of the adventitia as observed in Takayasu arteritis; other types of vasculitis were considered unlikely based on the symptoms and laboratory data. The patient was further diagnosed with giant cell arteritis, which was classified as a large vessel vasculitis along with Takayasu arteritis at the Chapel Hill Consensus Conference in 2012. This is a rare case of giant cell arteritis diagnosed in a patient with aortic dissection. The differences in histopathological findings between Takayasu arteritis and giant cell arteritis are discussed.

Central pathology review of salivary gland adenoid cystic carcinoma

BACKGROUND

To assess the role of a central pathology review in the diagnosis of salivary gland adenoid cystic carcinoma (AdCC).

METHODS

Surgically resected salivary gland tumors diagnosed as AdCC (n = 219) in 15 reference hospitals in Japan were subjected to a retrospective pathological re-evaluation.

RESULTS

After the review, the AdCC diagnosis was revised in 21/219 cases (9.6%). The six benign tumors (2.7%) comprised five basal cell adenomas and one pleomorphic adenoma, and among these six patients, three received postoperative radiotherapy. The remaining 15 malignant tumors (6.8%) comprised nine basal cell adenocarcinomas and six other carcinomas. All revised basal cell adenoma/adenocarcinoma cases were of rare cribriform variants.

CONCLUSIONS

A significant proportion of AdCC pathology reports were revised after the central pathology review. It should be emphasized that the greatest attention should be paid in differentiating AdCC from cribriform variant basal cell adenoma/adenocarcinoma, which is very rare in salivary gland tumors.

A new method for diagnosing biochemical abnormalities of anterior cruciate ligament (ACL) in human knees: A Raman spectroscopic study

Anterior cruciate ligament (ACL) plays an essential role in knee joint stability and kinematics. The microstructural irregularities such as cellular changes and disorganization of the extracellular matrix (ECM) alter the mechanical properties of the ligament, leading to a significant knee functional instability and progression of osteoarthritis (OA). So far, the identification of the local abnormality in ACL has routinely relied on invasive analytical techniques such as histology or biochemical assays. The non-invasive diagnosis using magnetic resonance imaging (MRI) is still limited to identifying the presence/absence of partial/complete ruptures and mucoid degeneration. In this study, laser micro-Raman spectroscopy with near-infrared excitation (785 nm) was applied to human ACL in order to establish optical algorithms for non-destructively diagnosing a degeneration state at molecular level. Raman spectra were obtained from 44 ex-vivo ACL specimens, and these were subsequently classified as an early (subclinical) and advanced (clinical) level of tissue degradation based on the histopathological scoring system. The significant differences in Raman peak intensities were found between the different degeneration groups, which were assigned to the vibrational modes of nucleic acids in cells, collagens, and phospholipids. Linear discriminant analysis (LDA) was performed to identify cut-off values for the distributions of Raman intensity and intensity ratios, which enable to best discriminate between the early and advanced degenerated tissues. Raman intensity algorithms derived from I₁₁₀₁/I₁₇₄₉, [I₁₀₀₂/I₁₅₁₆vs. I₁₁₀₁/I₁₇₄₉], and [I₁₀₀₂/I₁₇₄₉vs. I₁₁₀₁/I₁₇₄₉], yielded a maximum diagnostic sensitivity of 100%, specificity of 80%, and accuracy of 91% for discriminating the degeneration severity. STATEMENT OF SIGNIFICANCE: In this study, laser micro-Raman spectroscopy was applied to human anterior cruciate ligament (ACL) to establish optical algorithms for non-destructively diagnosing the tissue degeneration at molecular level. To our knowledge, this is the first report on Raman diagnosis for human ACL. Linear discriminant analysis (LDA) was performed to identify cut-off values for Raman intensity and intensity ratios, which enable to best discriminate between an early (subclinical) and advanced (clinical) level of ACL degeneration. The intensity ratios of I₁₁₀₁/I₁₇₄₉, [I₁₀₀₂/I₁₅₁₆vs. I₁₁₀₁/I₁₇₄₉], and [I₁₀₀₂/I₁₇₄₉vs. I₁₁₀₁/I₁₇₄₉] yielded a maximum diagnostic sensitivity of 100%, specificity of 80%, and accuracy of 91% for discriminating the ACL degeneration. The present findings might contribute to expanding clinical diagnostic possibilities for non-invasively identifying tissue degeneration.

The significance of micro-lymphatic invasion and pathological Gleason score in prostate cancer patients with pathologically organ-confined disease and negative surgical margins after robot-assisted radical prostatectomy

BACKGROUND

The development process of recurrence in prostate cancer patients with pathologically organ-confined (pT2) disease and negative surgical margins is unclear. The aim of the present study was to determine factors associated with the development of biochemical recurrence following robot-assisted radical prostatectomy among those prostate cancer patients.

METHODS

We retrospectively reviewed the data of patients who underwent robot-assisted radical prostatectomy without neoadjuvant endocrine therapy. We evaluated prognostic factors in 1096 prostate cancer patients with pT2 disease and negative surgical margins. Univariate and multivariate Cox proportional hazards regression analyses were used to identify independent predictors for biochemical recurrence.

RESULTS

Of the 1096 patients, 55 experienced biochemical recurrence during the follow-up period. The 5-year biochemical recurrence-free survival rate for patients with pT2 and negative surgical margins was 91.8%. On univariate analysis, clinical stage, biopsy Gleason score, percent of positive core, pathological Gleason score, and the presence of micro-lymphatic invasion were significantly associated with biochemical recurrence. On a multivariate analysis, the presence of micro-lymphatic invasion and a pathological Gleason score ≥ 4 + 3 were significant prognostic factors for biochemical recurrence. Based on these factors, we developed a risk stratification model. The biochemical recurrence-free survival rate differed significantly among the risk groups.

CONCLUSIONS

The prognosis of prostate cancer patients with pT2 disease and negative surgical margins is favorable. However, patients with the presence of micro-lymphatic invasion and a pathological Gleason score ≥ 4 + 3 tend to experience biochemical recurrence more often after surgery. Therefore, careful follow-up might be necessary for those patients.

First autopsy analysis of the efficacy of intra-operative additional photodynamic therapy for patients with glioblastoma

The study aim to demonstrate the therapeutic tissue depth of photodynamic therapy (PDT) using the photosensitizer talaporfin sodium and semiconductor laser for malignant glioma from an autopsy finding. Three patients diagnosed with glioblastoma by pre-operative imaging (1 newly diagnosed patient and 2 patients with recurrence) were treated with intra-operative additional PDT and adjuvant therapy such as post-operative radiotherapy or chemotherapy. All three patients died of brain stem dysfunction owing to cerebrospinal fluid dissemination or direct invasion of the tumor cells from 13, 18, or 20 months after PDT. Antemortem magnetic resonance images demonstrated no tumor recurrence in the site of PDT, and autopsy was performed for the pathological analysis. Macroscopic observation demonstrated no tumor recurrence in two patients, but one patient demonstrated tumor recurrence in the therapeutic depth of PDT. Microscopic analysis demonstrated histopathological changes reaching depths of 9, 11, and 18 mm (mean: 12.7 mm) from the surface of the cavity of tumor resection, suggesting the therapeutic tissue depth of PDT to be in this range. This region demonstrated glial scarring with infiltration of T lymphocytes and macrophages, with slight degeneration of small vessel walls. However, viable tumor tissues were observed beyond or around the therapeutic tissue depth of PDT in two patients. PDT for glioblastoma prevented early local recurrence, which suggests the possibility that activation of the immune mechanisms was involved. The therapeutic tissue depth was suggested to be 9-18 mm from the surface of the cavity of tumor resection; however, the viable tumor tissues were demonstrated beyond this therapeutic range.