Primary omental smooth muscle tumor in an adult male: a diagnostic dilemma for leiomyoma: a case report.

BACKGROUND: The greater omentum comprises peritoneal, adipose, vascular, and lymphoid tissues. Most omental malignancies are metastatic tumors, and the incidence of primary tumors is rare. We report on a prior omental smooth muscle tumor case in an adult male patient. CASE PRESENTATION: A 54-year-old Japanese male patient with no relevant medical history was diagnosed with an abdominal mass during a routine medical checkup. Subsequent contrast-enhanced computed tomography revealed a mass of approximately 3 cm in size in the greater omentum, and a laparotomy was performed. A 27 × 25 × 20 mm raised lesion was found in the omentum. Microscopically, spindle cells were observed and arranged in whorls and fascicles. Individual tumor cells had short spindle-shaped nuclei with slightly increased chromatin and were characterized by a slightly eosinophilic, spindle-shaped cytoplasm. The mitotic count was less than 1 per 50 high-power fields. The tumor cells showed positive immunoreactivity for α smooth muscle actin, HHF35, and desmin on immunohistochemical examination. The Ki-67 labeling index using the average method was 1.76% (261/14806). No immunoreactivity was observed for any of the other tested markers. We considered leiomyoma owing to a lack of malignant findings. However, primary omental leiomyoma has rarely been reported, and it can be difficult to completely rule out the malignant potential of smooth muscle tumors in soft tissues. Our patient was decisively diagnosed with a primary omental smooth muscle tumor considering leiomyoma. Consequently, the patient did not undergo additional adjuvant therapy and was followed up. The patient was satisfied with treatment and showed neither recurrence nor metastasis at the 13-month postoperative follow-up. DISCUSSION AND CONCLUSION: We encountered a primary smooth muscle tumor of the greater omentum with no histological findings suggestive of malignancy in an adult male patient. However, omental smooth muscle tumors are extremely difficult to define as benign, requiring careful diagnosis. Further case reports with long-term follow-up and case series are required to determine whether a true omental benign smooth muscle tumor (leiomyoma) exists. In addition, proper interpretation of the Ki-67 labeling index should be established. This case study is a foundation for future research.

A case of an unreported point mutation in promoter 1B of the adenomatous polyposis coli gene, which is responsible for gastric adenocarcinoma and proximal polyposis of the stomach.

A 35-year-old woman of Asian descent with epigastralgia was referred to our hospital. Esophagogastroduodenoscopy revealed gastric cancer in the upper body and carpeting fundic gland polyposis in the fornix and body. Computed tomography revealed no metastases. Total colonoscopy and capsule endoscopy revealed no polyposis, except in the stomach. The patient was diagnosed with advanced gastric cancer and underwent open total gastrectomy. We speculated that her gastric cancer was a hereditary tumor due to its early onset and accompanying fundic gland polyposis. Germline multi-gene panel testing identified a single-nucleotide variant, c.-191 T > G, in exon 1B of the adenomatous polyposis coli gene, which can cause gastric adenocarcinoma and proximal polyposis of the stomach. To our knowledge, this is the first manuscript to report the variant (c.-191 T > G) in promoter 1B of the adenomatous polyposis coli gene, which is related to a predisposition to gastric adenocarcinoma and proximal polyposis of the stomach.

Clinicopathological analysis of thyroid carcinomas with the RET and NTRK fusion genes: characterization for genetic analysis.

Thyroid carcinomas exhibit various genetic alterations, including the RET and NTRK fusion genes that are targets for molecular therapies. Thus, detecting fusion genes is crucial for devising effective treatment plans. This study characterized the pathological findings associated with these genes to identify the specimens suitable for genetic analysis. Thyroid carcinoma cases positive for the fusion genes were analyzed using the Oncomine Dx Target Test. Clinicopathological data were collected and assessed. Among the 74 patients tested, 8 had RET and 1 had NTRK3 fusion gene. Specifically, of the RET fusion gene cases, 6 exhibited "BRAF-like" atypia and 2 showed "RAS-like" atypia, while the single case with an NTRK3 fusion gene presented "RAS-like" atypia. Apart from one poorly differentiated thyroid carcinoma, most cases involved papillary thyroid carcinomas (PTCs). Primary tumors showed varied structural patterns and exhibited a high proportion of non-papillary structures. Dysmorphic clear cells were frequently observed. BRAF V600E immunoreactivity was negative in all cases. Interestingly, some cases exhibited similarities to diffuse sclerosing variant of PTC characteristics. While calcification in lymph node metastases was mild, primary tumors typically required hydrochloric acid-based decalcification for tissue preparation. This study highlights the benefits of combining morphological and immunohistochemical analyses for gene detection and posits that lymph node metastases are more suitable for genetic analysis owing to their mild calcification. Our results emphasize the importance of accurate sample processing in diagnosing and treating thyroid carcinomas.

Evaluation of pancreatic cancer specimens for comprehensive genomic profiling.

Inadequate specimen quality or quantity hinders comprehensive genomic profiling in identifying actionable mutations and guiding treatment strategies. We investigated the optimal conditions for pancreatic cancer specimen selection for comprehensive genomic profiling. We retrospectively analyzed 213 pancreatic cancer cases ordered for comprehensive genomic profiling and compared results from pancreatic biopsy, liver biopsy of pancreatic cancer metastases, pancreatectomy, liquid, and nonliver metastatic organ specimens. We examined preanalytical conditions, including cellularity (tumor cell count/size). The successfully tested cases were those that underwent comprehensive genomic profiling tests without any issues. The successfully tested case ratio was 72.8%. Pancreatic biopsy had the highest successfully tested case ratio (87%), with a high tumor cell percentage, despite the small number of cells (median, 3425). Pancreatic biopsy, liver biopsy of pancreatic cancer metastases, and non-liver metastatic organ had higher successfully tested case ratios than that for pancreatectomy. Liver biopsy of pancreatic cancer metastases and pancreatectomy cases with tumor size (mm2 ) × tumor ratio (%) > 150 and >3000, respectively, had high successfully tested case ratios. The success of comprehensive genomic profiling is significantly influenced by the tumor cell ratio, and pancreatic biopsy is a potentially suitable specimen for comprehensive genomic profiling.

Ten-year follow-up outcomes of limited resection trial for radiologically less-invasive lung cancer.

BACKGROUND: The JCOG0804/WJOG4507L single-arm confirmatory trial indicated a satisfactory 10-year prognosis for patients who underwent limited resection for radiologically less-invasive lung cancer. However, only one prospective trial has reported a 10-year prognosis. METHODS: We conducted a multicenter prospective study coordinated by the National Cancer Center Hospital East and Kanagawa Cancer Center. We analyzed the long-term prognosis of 100 patients who underwent limited resection of a radiologically less-invasive lung cancer in the peripheral lung field. We defined radiologically less-invasive lung cancer as lung adenocarcinoma with a maximum tumor diameter of ≤2 cm, tumor disappearance ratio of ≥0.5 and cN0. The primary endpoint was the 10-year local recurrence-free survival. RESULTS: Our patients, with a median age of 62 years, included 39 males. A total of 58 patients were non-smokers; 87 had undergone wide wedge resection and 9 underwent segmentectomy. A total of four cases were converted to lobectomy because of the presence of poorly differentiated components in the frozen specimen or insufficient margin with segmentectomy. The median follow-up duration was 120.9 months. The 10-year recurrence-free survival and overall survival rates of patients with lung cancer were both 96.0%. Following the 10-year long-term follow-up, two patients experienced recurrences at resection ends after wedge resection. CONCLUSIONS: Limited resection imparted a satisfactory prognosis for patients with radiologically less-invasive lung cancer, except two cases of local recurrence >5 years after surgery. These findings suggest that patients with this condition who underwent limited resection may require continued follow-up >5 years after surgery.

Mutation profile and programmed death ligand 1 status of patients with non-small cell lung cancer diagnosed with "adenocarcinoma" and "non-small cell carcinoma favor adenocarcinoma".

BACKGROUND: The terminology for lung cancer diagnosis in small biopsies was adopted in the 2015 World Health Organization classification. If non-small cell lung cancer (NSCLC) has no clear adenocarcinoma (AD) or squamous cell carcinoma morphology, the tumor is further classified based on mucin or immunohistochemical staining as NSCLC favor AD (NFAD), NSCLC favor squamous cell carcinoma, or NSCLC not otherwise specified. Since this new term was defined, the difference between AD and NFAD has not yet been fully explored. This study aimed to examine the differences in clinical background, gene alteration frequency, and programmed death ligand 1 (PD-L1) expression. METHODS: We included patients diagnosed with AD or NFAD with small samples, and who underwent testing with the Oncomine Dx target test between August 2019 and April 2023 in Kanagawa Cancer Center. RESULTS: This study comprised 268 patients. A total of 96 patients underwent surgery after AD or NFAD diagnosis. The clinical stage was more advanced and pathological N0 was lower in NFAD than in AD. The pathology of the surgical specimens revealed that solid predominant AD was significantly more common in NFAD than in AD (p < 0.001). In both AD and NFAD, EGFR mutation was the most frequent gene alteration, followed by KRAS mutation. The frequency of EGFR mutations was significantly higher in AD than in NFAD. PD-L1 expression was significantly higher in NFAD than in AD (p < 0.001). CONCLUSION: This study shows a clear difference between AD and NFAD in terms of cancer progression, pathological features of the main tumor, genetic characteristics, and PD-L1 expression.

Review of the Developing Landscape of Prostate Biopsy and Its Roles in Prostate Cancer Diagnosis and Treatment.

Prostate cancer remains a significant global health challenge. Traditionally anchored by the Gleason score/Grade Group (GS/GG), the landscape of prostate cancer diagnosis is undergoing transformative steps, particularly in the domain of biopsy procedures. GS/GG continues to be pivotal in malignancy grading, but recent technological strides have augmented the diagnostic relevance of biopsies. Integral to this progression is the adoption of advanced imaging techniques, especially magnetic resonance imaging, which has refined biopsy accuracy and efficiency. A deep understanding of prostate cancer pathology reveals a cribriform pattern and intraductal carcinoma of the prostate as independent forms of malignancy, suggesting a potentially aggressive disease course. Furthermore, the distinct behaviour of ductal adenocarcinoma and small cell carcinoma of the prostate, compared with acinar adenocarcinoma, necessitates their accurate differentiation during biopsy. The genomic era ushers in a renewed emphasis on tissue samples obtained from prostate biopsies, especially as mutations in genes, such as BRCA1/2, and paves the way for precision medicine. This review encapsulates the evolving dynamics of prostate biopsy, from technological advancements to the profound implications on prostate cancer management and therapy.

Genetic analysis of low-grade adenosquamous carcinoma of the breast progressing to high-grade metaplastic carcinoma.

PURPOSE: Low-grade adenosquamous carcinoma (LGASC) is a rare type of metaplastic carcinoma of the breast (MBC) with an indolent clinical course. A few LGASC cases with high-grade transformation have been reported; however, the genetics underlying malignant progression of LGASC remain unclear. METHODS: We performed whole-genome sequencing analysis on five MBCs from four patients, including one case with matching primary LGASC and a lymph node metastatic tumor consisting of high-grade MBC with a predominant metaplastic squamous cell carcinoma component (MSC) that progressed from LGASC and three cases of independent de novo MSC. RESULTS: Unlike de novo MSC, LGASC and its associated MSC showed no TP53 mutation and tended to contain fewer structural variants than de novo MSC. Both LGASC and its associated MSC harbored the common GNAS c.C2530T:p.Arg844Cys mutation, which was more frequently detected in the cancer cell fraction of MSC. MSC associated with LGASC showed additional pathogenic deletions of multiple tumor-suppressor genes, such as KMT2D and BTG1. Copy number analysis revealed potential 18q loss of heterozygosity in both LGASC and associated MSC. The frequency of SMAD4::DCC fusion due to deletions increased with progression to MSC; however, chimeric proteins were not detected. SMAD4 protein expression was already decreased at the LGASC stage due to unknown mechanisms. CONCLUSION: Not only LGASC but also its associated high-grade MBC may be genetically different from de novo high-grade MBC. Progression from LGASC to high-grade MBC may involve the concentration of driver mutations caused by clonal selection and inactivation of tumor-suppressor genes.

Histological findings of thyroid cancer after lenvatinib therapy.

AIMS: Lenvatinib is a multikinase inhibitor used for treating unresectable or metastatic cancers, including thyroid cancer. As total thyroidectomy followed by radioactive iodine therapy is a commonly recommended initial treatment for thyroid cancer, histological findings of the thyroid after lenvatinib therapy remain unclear. Therefore, the aim of this study was to analyse in-vivo changes in patients who underwent thyroidectomy after lenvatinib therapy. METHODS AND RESULTS: We screened 167 patients with thyroid cancer [papillary thyroid cancer (PTC), n = 102; follicular thyroid cancer (FTC), n = 26; anaplastic thyroid cancer (ATC), n = 39] who underwent lenvatinib therapy. Among these patients, six underwent thyroidectomy (lenvatinib-treated group: PTC, n = 3; FTC, n = 1; ATC, n = 2), and the specimens were examined. Five patients with PTC who did not receive lenvatinib therapy were included for comparison (untreated group). Microvessel density (MVD) was evaluated in both groups. The PTC and FTC specimens showed relatively more ischaemic changes than ATC specimens. Coagulative necrosis and ischaemic changes in cancer cells were frequently observed. ATC specimens showed fibrosis and mild cell damage. As hypothyroidism is a common side effect of lenvatinib therapy, non-cancerous thyroid tissues were also examined. Histological findings included mild lymphocytic infiltration, lymphoid follicular formation, histiocytic reaction and follicular epithelial destruction. The MVD in lenvatinib-treated tissues was significantly lower than that in untreated tissues. CONCLUSIONS: Lenvatinib therapy probably induces relatively specific ischaemic changes in thyroid cancer cells. Moreover, inflammatory cell infiltration and decreased MVD occur to varying degrees in non-cancerous thyroid tissue and may be related to hypothyroidism, a side effect of lenvatinib.

Histological markers, sickle-shaped blood vessels, myxoid area, and infiltrating growth pattern help stratify the prognosis of patients with myxofibrosarcoma/undifferentiated sarcoma.

Myxofibrosarcoma (MFS) and undifferentiated sarcoma (US) have been considered as tumors of the same lineage based on genetic/epigenetic profiling. Although MFS shows a notably better prognosis than US, there are no clear criteria for distinguishing between them. Here, we examined 85 patients with MFS/US and found that tumors with infiltrative growth patterns tended to have more myxoid areas and higher local recurrence rates but fewer distant metastases and better overall survival. Morphologically characteristic sickle-shaped blood vessels, which tended to have fewer αSMA-positive cells, were also observed in these tumors, compared with normal vessels. Based on the incidence of these sickle-shaped blood vessels, we subdivided conventionally diagnosed US into two groups. This stratification was significantly correlated with metastasis and prognosis. RNA sequencing of 24 tumors (9 MFS and 15 US tumors) demonstrated that the proteasome, NF-kB, and VEGF pathways were differentially regulated among these tumors. Expression levels of KDR and NFATC4, which encode a transcription factor responsible for the neuritin-insulin receptor angiogenic signaling, were elevated in the sickle-shaped blood vessel-rich US tumors. These findings indicate that further analyses may help elucidate the malignant potential of MFS/US tumors as well as the development of therapeutic strategies for such tumors.

Bone marrow adipocytes induce cancer-associated fibroblasts and immune evasion, enhancing invasion and drug resistance.

Bone metastasis occurs frequently in cancer patients. Conventional therapies have limited therapeutic outcomes, and thus, exploring the mechanisms of cancer progression in bone metastasis is important to develop new effective therapies. In the bone microenvironment, adipocytes are the major stromal cells that interact with cancer cells during bone metastasis. However, the comprehensive functions of bone marrow adipocytes in cancer progression are not yet fully understood. To address this, we investigated the role of bone marrow adipocytes on cancer cells, by focusing on an invasive front that reflects the direct effects of stromal cells on cancer. In comprehensive histopathological and genetic analysis using bone metastasis specimens, we examined invasive fronts in bone metastasis and compared invasive fronts with adipocyte-rich bone marrow (adipo-BM) to those with hematopoietic cell-rich bone marrow (hemato-BM) as a normal counterpart of adipocytes. We found morphological complexity of the invasive front with adipo-BM was significantly higher than that with hemato-BM. Based on immunohistochemistry, the invasive front with adipo-BM comparatively had a significantly increased cancer-associated fibroblast (CAF) marker-positive area and lower density of CD8+ lymphocytes compared to that with hemato-BM. RNA sequencing analysis of primary and bone metastasis cancer revealed that bone metastasized cancer cells acquired drug resistance-related gene expression phenotypes. Clearly, these findings indicate that bone marrow adipocytes provide a favorable tumor microenvironment for cancer invasion and therapeutic resistance of bone metastasized cancers through CAF induction and immune evasion, providing a potential target for the treatment of bone metastasis.

Cribriform pattern and intraductal carcinoma of the prostate can have a clinicopathological impact, regardless of their percentage and/or number of cores.

Cribriform pattern and intraductal carcinoma of the prostate (IDC-P) are widely accepted as poor prognostic factors in prostate cancer. However, it remains unclear to what extent the presence of these morphological features in prostate biopsy specimens, as diagnosed by hematoxylin-eosin-stained specimens only, affects the clinicopathological impact. In this study, we summarized the characteristics of the cribriform pattern and IDC-P in 850 prostate biopsy cases. The results showed a statistically significant increase in the incidence of cribriform pattern and IDC-P as grade group (GG) increased (especially in cases ≥ GG4, Chi-square test P < 0.001). The independent risk factors for cribriform pattern and IDC-P in biopsy specimens in the multivariate logistic regression analysis were the former GG, presence of IDC-P, lesion length of the highest GG core, latter GG, presence of the cribriform pattern, number of biopsies obtained, and number of highest GG core. Overall, 125 cases in which radical prostatectomy was conducted after biopsy were selected for further analysis. Multivariate logistic regression analysis using biopsy and surgical specimens confirmed that the presence of the cribriform pattern and IDC-P in biopsy specimens were independent risk factors for lymph node metastasis (odds ratios [95% confidence interval] were 6.54 [1.15-37.05] for the cribriform pattern and 23.71 [1.74-322.42] for IDC-P). The presence of the cribriform pattern and/or IDC-P in a biopsy specimen was a significant factor, even if only partially present, indicating lymph node metastasis. However, further validation is required to predict poor prognostic factors more accurately.

Differential diagnosis of uterine adenosarcoma: identification of JAZF1-BCORL1 rearrangement by comprehensive cancer genomic profiling.

BACKGROUND: Uterine adenosarcoma is a rare malignant tumor that accounts for 8% of all uterine sarcomas, and less than 0.2% of all uterine malignancies. However, it is frequently misdiagnosed in clinical examinations, including pathological diagnosis, and imaging studies owing to its rare and non-specific nature, which is further compounded by the lack of specific diagnostic markers. CASE PRESENTATION: We report a case of uterine adenosarcoma for which a comprehensive genomic profiling (CGP) test provided a chance to reach the proper diagnosis. The patient, a woman in her 60s with a history of uterine leiomyoma was diagnosed with an intra-abdominal mass post presentation with abdominal distention and loss of appetite. She was suspected to have gastrointestinal stromal tumor (GIST); the laparotomically excised mass was found to comprise uniform spindle-shaped cells that grew in bundles with a herringbone architecture, and occasional myxomatous stroma. Immunostaining revealed no specific findings, and the tumor was diagnosed as a spindle cell tumor/suspicious adult fibrosarcoma. The tumor relapsed during postoperative follow-up, and showed size reduction with chemotherapy, prior to regrowth. CGP was performed to identify a possible treatment, which resulted in detection of a JAZF1-BCORL1 rearrangement. Since the rearrangement has been reported in uterine sarcomas, we reevaluated specimens of the preceding uterine leiomyoma, which revealed the presence of adenosarcoma components in the corpus uteri. Furthermore, both the uterine adenosarcoma and intra-abdominal mass were partially positive for CD10 and BCOR staining. CONCLUSION: These results led to the conclusive identification of the abdominal tumor as a metastasis of the uterine adenosarcoma. The JAZF1-BCORL1 rearrangement is predominantly associated with uterine stromal sarcomas; thus far, ours is the second report of the same in an adenosarcoma. Adenosarcomas are rare and difficult to diagnose, especially in atypical cases with scarce glandular epithelial components. Identification of rearrangements involving BCOR or BCORL1, will encourage BCOR staining analysis, thereby potentially resulting in better diagnostic outcomes. Given that platinum-based chemotherapy was proposed as the treatment choice for this patient post diagnosis with adenosarcoma, CGP also indirectly contributed to the designing of the best-suited treatment protocol.

[Spontaneous remission of primary breast diffuse large B-cell lymphoma].

A 71-year-old woman became aware of a 25-mm mass in her right breast as identified by her previous doctor. Needle biopsy findings suggested malignant lymphoma, and she was referred to our hospital for further evaluation. She was diagnosed with diffuse large B-cell lymphoma (DLBCL) at our hospital. Positron emission tomography-computed tomography (PET-CT) revealed an elevated SUVmax (maximum standardized uptake value; 10.3), with the mass localized in the right breast, but magnetic resonance imaging findings revealed that the mass had shrunk to 10 mm. Needle biopsy was repeated in our hospital, and lymphoma cells were absent. Two months later, CT scan revealed complete disappearance of the mass, and, since then, the patient has been free of recurrence. Although there are reports of spontaneous remission of nonHodgkin's lymphoma, it is rare in the case of high-grade B-cell lymphoma. The mechanism of spontaneous remission is unclear; however, advancing age, localized stage, activated B-cell (ABC) or nongerminal center B-cell (GCB) type, and a history of infection are the associated factors. The findings from this case suggest that DLBCL can be cured without therapeutic intervention; however, careful followup may be needed.

Chronological Change in EPHA2 Protein Expression Is Associated With Recurrence of Bladder Cancer.

BACKGROUND/AIM: Bladder cancer is the most common urinary tract cancer. Patients diagnosed with advanced T-stage/muscle-invasive bladder cancer through transurethral resection of bladder tumors (TURBT) are treated with total radical cystectomy; however, there is a high chance of recurrence. Nevertheless, markers for predicting this recurrence are not currently available. Here, we evaluated the chronological change of ephrin type-A receptor 2 (EPHA2) expression, a molecule known for its role in cell adhesion, to predict bladder cancer recurrence after cystectomy, using TURBT and cystectomy specimens. MATERIALS AND METHODS: An immunostaining evaluation method that combines whole-slide images and image analysis software was developed to quantify and evaluate stainability objectively. We assessed the correlation between EPHA2 expression and bladder cancer recurrence using this novel immunostaining method and chronological changes in target protein expression in TURBT and radical cystectomy samples. RESULTS: In TURBT specimens, the number of cases with a high N-terminal/C-terminal EPHA2 ratio in the group with recurrence was significantly higher than in the non-recurrent group (p=0.019). The number of cases with a high level of C-terminal EPHA2 positivity in the radical cystectomy specimen when compared to the TURBT specimen obtained from the same patient was significantly higher in the recurrent group than in the non-recurrent group (p=0.0034). CONCLUSION: EPHA2 appears to be a promising marker for bladder tumor recurrence after cystectomy and its evaluation may enable the selection of appropriate cases for adjuvant therapy among patients undergoing radical cystectomy. Further studies, including mass-scale analysis, are required to confirm these results.

[Metastatic Tumor of the Uterine Cervical Cancer Occurred in the Infratemporal Fossa].

A 46-year-old woman presented with discomfort in her right lateral gaze, right-sided headache, and facial numbness 17 days after concurrent chemoradiotherapy(CCRT)for a Stage ⅢB cervical cancer. The initial imaging investigations, maxillofacial and otolaryngology reviews did not reveal a diagnosis. After 54 days of CCRT, her symptoms deteriorated. Magnetic resonance imaging(MRI)showed a tumor in the right infratemporal fossa and its biopsy confirmed a metastatic cervical cancer. In view of the rapid deterioration and the potential visual loss, palliative intensity-modulated radiotherapy(IMRT) was given. Although the symptoms improved temporarily, multiple metastases were subsequently found. Despite chemotherapy, the patient died 11 months after developing the symptoms of infratemporal fossa metastasis.

Significance of non-standardized magnetic resonance imaging abnormalities and subsequent targeted prostate cancer biopsy for pathologists: A retrospective observational study.

Prostate biopsy is essential in diagnosing prostate cancer. The Prostate Imaging-Reporting and Data System (PI-RADS) and magnetic resonance imaging (MRI)-transrectal ultrasound fusion-guided biopsy are also useful for diagnosis. However, the burden of implementing and maintaining these techniques should be considered. Therefore, we investigated the significance of non-standardized pre-biopsy MRI abnormalities (conditions not in accordance with PI-RADS) and subsequent targeted biopsy. We collected clinicopathological data, including the presence or absence of MRI abnormalities, through biopsies from January 2017 to February 2022 at the Kanagawa Cancer Center and performed statistical analyses. We enrolled in 1086 cases: MRI abnormalities were observed in 861 cases (79.3%). In these 861 cases, the adenocarcinoma detection rate, number of positive cores, and length of the highest Grade Group (GG) lesions were significantly higher. In the multivariate analysis, MRI abnormalities were the most significant factor for detecting adenocarcinoma of ≥GG 2 (odds ratio: 4.52, 95% confidence interval: 3.08-6.63). Targeted biopsy showed a higher percentage of positive cores with ≥GG2 and longer highest GG lesion lengths than systematic biopsy. Furthermore, the highest GG was upgraded in 109 of 788 cases by targeted biopsy. However, several adenocarcinomas (125/788; 15.9%) could not be detected using only targeted biopsy. Non-standardized MRI abnormalities are powerful predictors of cancer and grading. Targeted biopsies based on MRI abnormalities provide several benefits. Owing to the relatively low implementation hurdle, these biopsies may serve as a bridge until the ideal approaches are popularized if the limitations are well understood.

Diagnostic significance of reassessment of prostate biopsy specimens by experienced urological pathologists at a high-volume institution.

In prostate cancer, accurate diagnosis and grade group (GG) decision based on biopsy findings are essential for determining treatment strategies. Diagnosis by experienced urological pathologists is recommended; however, their contribution to patient benefits remains unknown. Therefore, we analyzed clinicopathological information to determine the significance of reassessment by experienced urological pathologists at a high-volume institution to identify factors involved in the agreement or disagreement of biopsy and surgical GGs. In total, 1325 prostate adenocarcinomas were analyzed, and the GG was changed in 452/1325 (34.1%) cases (359 cases were upgraded, and 93 cases were downgraded). We compared the highest GG based on biopsy specimens, with the final GG based on surgical specimens of 210 cases. The agreement rate between the surgical GG performed and assessed in our institute and the highest biopsy GG assessed by an outside pathologist was 34.8% (73/210); the agreement rate increased significantly to 50% (105/210) when biopsy specimens were reevaluated in our institute (chi-square test, P < 0.01). Multivariate logistic regression analysis showed that only the length of the lesion in the positive core with the highest GG in the biopsy was a significant factor for determining the agreement between biopsy GG and surgical GG, with an odds ratio of 1.136 (95% confidence interval: 1.057-1.221; P < 0.01). Thus, reassessment by experienced urological pathologists at high-volume institutions improved the agreement rate. However, it should be noted there is a high probability of discordance between a small number of lesions or short lesions and surgical GG.

Clinicopathological and genetic analyses of small cell neuroendocrine carcinoma of the prostate: Histological features for accurate diagnosis and toward future novel therapies.

Differentiating small cell neuroendocrine (NE) carcinoma (SCNC) of the prostate from adenocarcinoma with NE differentiation based on morphological features alone sometimes can be challenging. Given that treatment strategies vary depending on histological type, an accurate diagnosis is critical. This study aimed to identify the accurate diagnostic factors for SCNC of the prostate. Furthermore, the possibility of novel treatment strategies through genetic analysis was also investigated. Prostate biopsies conducted in our hospital between January 2017 and May 2020 were included. Consequently, seven cases of SCNC and four cases of adenocarcinoma with NE differentiation were identified. No significant differences in the serum neuron-specific enolase, pro-gastrin-releasing peptide, and prostate-specific antigen (PSA) levels were observed between both tumors. The Ki-67 labeling index was significantly higher, and PSA immunoreactivity tended to be lower in SCNC. Although the morphology was undetectable, genetic analysis confirmed several mutations, including those of PIK3CA and TP53. The fact that morphological findings are not apparent indicates that genetic investigation rather than only morphological findings would be important in the future. In conclusion, given the heterogeneity of serum NE markers in SCNC, diagnosis based on these markers alone is challenging. A high Ki-67 labeling index and low PSA immunoreactivity may be useful for diagnosis, but p53 immunoreactivity is insufficient in distinguishing. Although further studies are required to interpret the results of the genetic analysis involving ALK, PIK3CA, and TP53 mutations, the results of our genetic analysis suggest that PIK3CA mutations in SCNC of the prostate may provide a novel therapeutic strategy.

Clinicopathological Analysis of the ISUP Grade Group And Other Parameters in Prostate Cancer: Elucidation of Mutual Impact of the Various Parameters.

BACKGROUND: Prostate cancer has become increasingly common worldwide. Although Grade group (GG) is widely accepted as an indicator of prostate cancer grade, there are malignancies that cannot be defined by GG alone. Moreover, the relationship between GG and other parameters remains unclear. Herein, we aimed to explore the biological characteristics of prostate cancer. METHODS: This study included 299 radical prostatectomy cases. The Chi-square test and analysis of variance were used to analyze the association of GG with binary and continuous variables. We then conducted morphological analyses. Multivariate analyses were performed to extract the data on risk factors for biochemical recurrence (BCR) and lymph node metastasis. RESULTS: The lymphatic, venous, perineural, and seminal vesicle invasion rates were 37/299 (12.4%), 25/299 (8.4%), 280/299 (93.6%), and 23/299 (7.7%), respectively. The extraprostatic extension (EPE), positive surgical margin, tertiary Gleason pattern 5, intraductal carcinoma of the prostate gland, and lymph node metastasis rates were 89/299 (29.8%), 106/299 (35.5%), 33/260 (12.7%), 56/299 (18.7%), and 23/299 (7.7%), respectively. As GG increased, various parameters became easier to visualize; however, there were differences between the parameters. Postoperative BCR was observed in 31/242 (12.8%) cases without preoperative hormone therapy; GG2, GG3, GG4, and GG5 accounted for 4, 7, 7, and 13 cases, respectively. Multivariate analyses revealed that GG and tumor diameter were significant risk factors for early BCR, whereas lymphatic invasion, EPE, and seminal vesicle invasion were significant risk factors for lymph node metastasis. For BCR, the odds ratios (ORs) for GG and tumor diameter were 2.253 (95% confidence interval (CI]): 1.297-3.912; P=0.004) and 1.074 (95% CI: 1.011-1.142; P=0.022), respectively. For lymph node metastasis, ORs for the presence of lymphatic invasion, EPE, and seminal vesicle invasion were 7.425 (95% CI: 1.688-22.583; P=0.004), 4.391 (95% CI: 1.037-18.589; P=0.044), and 5.755 (95% CI: 1.308-25.316; P=0.021), respectively. CONCLUSIONS: We summarized various parameters correlating with each GG. Through multivariate analyses, we established the independent risk factors for early BCR and lymph node metastasis. In addition to GG, other important indices of malignancy were determined and weighted to provide a basis for future investigations.