A New Self-Expandable Metallic Stent with Low Axial Force and a High Axial Force Zero-Border Shows a Very Low Perforation Rate in Malignant Colorectal Obstruction: A Japanese Multicenter Prospective Study.

Background: Recently, there has been a significant increase in the utilization of self-expandable metallic stents (SEMSs) for treating malignant colorectal obstructions through colorectal stenting. The mechanical properties of SEMSs are usually considered to affect clinical outcomes of patients with malignant colorectal obstructions. Methods: This single-arm, prospective, multicenter study of SEMS with a lower axial force and high axial force zero-border included 200 patients with malignant colorectal obstruction. Technical and clinical success, stent patency, and adverse events associated with SEMS placement were evaluated. Results: One patient was excluded, and 199 patients were evaluated. The treatment intent was bridge-to-surgery in 129 and palliation in 70 patients. Technical and clinical success rates were 99.5% and 97.0%, respectively. The percentage of the ColoRectal Obstruction Scoring System scores of 3 or higher improved significantly from 19.2% before placement to 93.9% after placement. Clinical success was not achieved in five patients due to insufficient stent expansion in four patients and stent occlusion in one patient. Only one patient underwent emergency surgery for perforation of the proximal colon, far from where the stent was placed; the rescue procedure was not performed, despite no improvement in proximal dilatation due to insufficient stent expansion. Among the palliation cohort, 15 patients received chemotherapy, including molecular-targeted agents such as bevacizumab. There were no fatal cases related to stent placement. Conclusions: For management of malignant colorectal obstruction, this newly developed SEMS with low axial force and a high axial force zero-border showed high technical and clinical success rates, and an extremely low perforation rate (0.5%).

Fully digitalized triple-energy x-ray computed tomography with high spatial resolutions using beam hardening.

To regulate the effective photon energy with a constant tube voltage and to perform enhanced K-edge x-ray imaging, we built a prototype fully digitalized triple-energy x-ray computed tomography (TECT) scanner utilizing beam hardening. An object on the turntable is irradiated by a 0.1-mm-focus x-ray tube at 1.4-time-magnification. 720 raw radiograms are obtained using a flat panel detector, and 512 tomograms are reconstructed. With an increasing digital amplification factor, the gray raw-density projections obtained using low-energy-photon absorption disappeared at a constant maximum raw density, and the effective energy was increased by x-ray beam hardening. TECT was performed at digital amplifier factors below 3.0, and the effective energy increased with increasing amplification factors. In particular, fine blood vessels were visible using gadolinium-K-edge CT.

Embossed x-ray computed tomography utilizing pixel-shifted dual-energy subtraction.

To observe fine blood vessels as uneven tomographic images at a high contrast, we performed tentative experiments on embossed x-ray computed tomography (CT). We constructed a cone-beam CT scanner and carried out dual-energy CT with tube voltages of 60 and 100 kV. X-ray photons penetrating through an object were detected using an indirect-conversion flat panel detector, and radiograms were produced and sent to a personal computer to reconstruct tomograms. Embossed CT was performed using pixel-shifted dual-energy subtraction, and blood vessels filled with Gd medium were observed as uneven images at high contrast and spatial resolutions. Using 1.4-time magnification imaging in combination with a 0.1-mm-focus x-ray tube, the diameter of the object visible on the embossed CT was below 100 µm.

Right-sided versus left-sided colorectal cancer in elderly patients: a sub-analysis of a large multicenter case-control study in Japan.

PURPOSE: This study investigated the impact of sidedness of colorectal cancer (CRC) in elderly patients on the prognosis. METHODS: In a sub-analysis of a multicenter case-control study of CRC patients who underwent surgery at ≥ 80 years old conducted in Japan between 2003 and 2007, both short- and long-term outcomes were compared between right-sided colon cancers (RCCs) and left-sided colorectal cancers (LCCs). RCCs were defined as those located from the cecum to the transverse colon. RESULTS: Among the 1680 patients who underwent curative surgery, 812 and 868 had RCCs and LCCs, respectively. RCCs were more frequent than LCCs in those who were female, had renal comorbidities, and had a history of abdominal surgery. Regarding tumor characteristics, RCCs were larger, invaded more deeply, and were diagnosed as either mucinous or signet ring-cell carcinoma more frequently than LCCs. Regarding the prognosis, patients with RCCs had a significantly longer cancer-specific survival (CS-S) and cancer-specific relapse-free survival (CS-RFS) than those with LCCs. Furthermore, sidedness was determined to be an independent prognostic factor for CS-S and CS-RFS. CONCLUSION: RCCs, which accounted for half of the cases in patients ≥ 80 years old, showed better long-term outcomes than LCCs.

Four Cases of Proximal Release-Type Colon Stents for Obstructive Rectal Cancer.

Malignant colonic obstruction can cause necrosis, bacterial translocation, electrolytic imbalance, and death; therefore, immediate decompression should be performed. Self-expandable metallic colonic stents are an established treatment for the decompression of malignant colonic obstructions. The use of stents that open from the distal side, which have been commonly used until now, requires caution because placing a stent on the dentate line can cause severe pain, and there is a possibility of cutting the stent during rectal resection of the distal side of the tumor. Therefore, we designed a new proximal-release-type colorectal stent for use in our hospital; it is 22 mm in diameter and 70 mm in length, which was placed using the over-the-wire method with a 16 Fr delivery system. We have encountered four cases in which it was appropriate as a bridge to surgical treatment. None of the patients experienced complications, such as bleeding, pain, or other incidents, after stent placement. Additionally, the stents were not affected by the surgical dissection of the rectum on the anorectal side of the tumor. Herein, we presented the four aforementioned cases and discussed the stenting techniques.

Two cases of laparoscopic deroofing of giant liver cysts using indocyanine green fluorescence imaging.

Laparoscopic deroofing (LD) for giant liver cysts using indocyanine green (ICG) fluorescence imaging was performed in two patients: a 53-year-old man with a 26-cm, symptomatic cyst and a 50-year-old woman with a 13-cm, symptomatic cyst. ICG fluorescence imaging can be used to easily identify the boundary between the liver parenchyma and the liver cyst. No postoperative bile leakage was observed in both patients. ICG fluorescence imaging is expected to become a desirable procedure in LD for giant liver cysts to reduce the occurrence of perioperative complications.

[Collision Tumor Involving Primary Ascending Colon Cancer and Malignant Lymphoma].

A 78-year-old male was diagnosed with a primary gastric B-cell malignant lymphoma and metastatic lung tumor 10 years ago. He underwent chemotherapy at another hospital, achieved complete remission, and was actively undergoing follow- up. He presented to our hospital with a 1-month history of a bulge in his right lower abdomen. CT revealed thickening of the ascending colon and dilatation of the oral intestine. He was diagnosed with ascending colon cancer and underwent right hemicolectomy. The subsequent pathological examination revealed a collision tumor involving diffuse, large B-cell lymphoma and well-differentiated adenocarcinoma. He was discharged from our hospital and received chemotherapy at another institution. Unfortunately, the patient died of interstitial pneumonia 31 months postoperatively. This report describes the resection of a collision tumor involving ascending colon cancer and malignant lymphoma. Surgical treatment combined with postoperative chemotherapy improved this patient's long-term survival.

Clinicopathologic analysis of pineal parenchymal tumors of intermediate differentiation: a multi-institutional cohort study by the Kyushu Neuro-Oncology Study Group.

PURPOSE: Pineal parenchymal tumors of intermediate differentiation (PPTIDs), which were recognized in the 2007 World Health Organization (WHO) classification, are rare, accounting for less than 1% of all central nervous system tumors. This rarity and novelty complicate the diagnosis and treatments of PPTID. We therefore aimed to evaluate the clinicopathological significance of this tumor. METHODS: At 11 institutions participating in the Kyushu Neuro-Oncology Study Group, data for patients diagnosed with PPTID were collected. Central pathology review and KBTBD4 mutation analysis were applied to attain the diagnostically accurate cohort. RESULTS: PPTID was officially diagnosed in 28 patients: 11 (39%) with WHO grade 2 and 17 (61%) with WHO grade 3 tumors. Median age was 49 years, and the male:female ratio was 1:2.1. Surgery was attempted in all 28 patients, and gross total resection (GTR) was achieved in 46% (13/28). Adjuvant radiotherapy and chemotherapy were administered to, respectively, 82% (23/28) and 46% (13/28). The 5-year progression-free survival (PFS) and overall survival rates were 64.9% and 70.4% respectively. Female sex (p = 0.018) and GTR (p < 0.01) were found to be independent prognostic factors for PFS and female sex (p = 0.019) was that for OS. Initial and second recurrences were most often leptomeningeal (67% and 100% respectively). 80% (20/25) of patients harbored a KBTBD4 mutation. CONCLUSIONS: Female sex and GTR were independent prognostic factors in our patients with PPTID. Leptomeningeal recurrence was observed to be particularly characteristic of this tumor. The rate of KBTBD4 mutation observed in our cohort was acceptable and this could prove the accuracy of our PPTID cohort.

[Malignant Melanoma of a Male Breast That Was Difficult to Differentiate from Breast Cancer-A Case Report].

INTRODUCTION: Malignant melanoma in the male breast is extremely rare. Here we report a case of malignant melanoma in which a small cystic lesion in the male breast gradually increased during follow-up and was difficult to distinguish from breast cancer. CASE: A 65-year-old male was diagnosed with a tumor in the right breast and was referred to our department for further examination. At 42 years of age, he underwent tumor resection of a malignant melanoma of the abdominal skin. Mammary ultrasonography showed a 0.6 cm cystic mass in his right breast. Eight months later, the right breast mass had increased to 1.4 cm, and a core needle biopsy suggested breast cancer. Total mastectomy with axillary lymph node dissection was performed. HE staining of the resected tumor showed intranuclear inclusion bodies and some large nucleoli. On the basis of various immunostaining methods, malignant melanoma was diagnosed instead of breast cancer. After surgery, adjuvant chemotherapy with molecularly targeted drugs was administered. DISCUSSION: This might have been a case of male breast metastasis of malignant melanoma with very late recurrence.

[Laparoscopic Tumor Resection for Asymptomatic Paraganglioma-A Case Study].

A 55-year-old man was referred for the close examination of an abdominal mass noted on abdominal ultrasonography during a physical examination. A contrast-enhanced computed tomography(CT)scan of his abdomen revealed a 36-mm heterogeneously contrast-enhanced mass on the left side of the aorta. He was referred for laparoscopic tumor resection without preoperative histological examination. The tumor was identified from the dorsal aspect of the mesentery of the transverse colon and was resected only because it was detachable from the duodenum. A temporary abnormal hypertension was observed intraoperatively. However, he exhibited a favorable postoperative course and was discharged on the 8th postoperative day. Grossly, it was a nodular tumor with a diameter of 38 mm. Histopathological examination revealed that the tumor cells having abundant cytoplasm formed large foci and were surrounded by sinusoidal vessels. Immunohistochemistry results were positive for chromogranin A, synaptophysin, and neural cell adhesion molecule; thus, paraganglioma was diagnosed. Herein, we report a case of laparoscopic resection of an asymptomatic paraganglioma.

Favorable management of symptomatic cerebellar hemangioblastoma presenting with obstructive hydrocephalus during pregnancy: A case report and literature review.

Background: Cerebellar hemangioblastoma is a highly vascular benign tumor and the growth rate of hemangioblastomas is believed to often accelerate during pregnancy; however, the reason for this rapid increase in size remains poorly understood. There are several case reports of symptomatic hemangioblastoma during pregnancy; however, the favorable management strategy has not been well established. Case Description: A 35-year-old woman, gravida 2 para 1, with no significant medical history presented with vertigo and difficulty walking at around 11 weeks of pregnancy and was referred to our institute at 30 weeks of gestation because of worsening symptoms. Brain magnetic resonance imaging revealed a 5.6 cm cystic lesion with a mural nodule in the right cerebellar hemisphere and the lesion blocked cerebrospinal fluid drainage from the fourth ventricle and brainstem, resulting in obstructive hydrocephalus. After obtaining the patient's consent, a multidisciplinary team consisting of obstetricians and neurosurgeons decided to perform resection of the intracranial lesion following delivery of the fetus by emergency cesarean section in view of the symptoms of increased intracranial pressure. The patient's general condition was confirmed to be stable postoperatively and she was discharged on the 16th day of her hospitalization without any neurological deficits or fetal complications. Conclusion: Urgent tumor resection combined with cesarean section can be planned once fetal lung maturity is confirmed. Most cases of symptomatic hemangioblastoma during pregnancy have an uneventful gestational course and a favorable outcome for both mother and child.

A case of pituitary adenoma with infiltration into the sphenoid sinus accompanied by melanocyte proliferation.

A 71-year-old woman presenting with headache and nausea was admitted to hospital. Magnetic resonance imaging revealed a tumorous lesion that surrounded the sella turcica and infiltrated the sphenoid sinus with bone destruction. The tumor was removed by nasal endoscopy. The histology was consistent with pituitary adenoma; immunohistochemistry indicated silent corticotroph adenoma with melanocyte proliferation. The possibility that melanocytes were incorporated into the tumor mass in the sphenoid sinus and underwent proliferation was evaluated by investigating the mechanisms of melanocyte proliferation associated with basic fibroblast growth factor (bFGF) and α melanocyte-stimulating hormone (αMSH). In the normal tissue, the pars intermedia and adrenocorticotropic hormone (ACTH)-producing cells were positive for αMSH. None of the control adenoma tissues were positive for bFGF or αMSH by immunostaining. In the present case, bFGF-positive cells and αMSHpositive cells were observed, suggesting that both may have been involved in melanocyte proliferation. The expression of bFGF has been linked to aggressive disease. Pituitary adenoma with melanocyte proliferation has not been previously reported. Careful follow-up is deemed necessary in the future.

Long-term outcomes of standardized colonic stenting using WallFlex as a bridge to surgery: Multicenter prospective cohort study.

OBJECTIVES: The oncological outcomes, especially high recurrence rate, of bridge-to-surgery (BTS) self-expandable metallic stent (SEMS) placement remain concerning, emphasizing the necessity of standardized SEMS placement. However, its impact on long-term BTS outcomes is unknown. We investigated the long-term outcomes of BTS colonic stenting using standardized SEMS placement. METHODS: This prospective, multicenter cohort study conducted at 46 hospitals in Japan (March 2012 to October 2013) included consecutive patients with stage II and III obstructive colorectal cancer managed with BTS SEMS placement. The SEMS placement technique was standardized by information dissemination among the participating hospitals. The primary outcome was overall survival (OS) after SEMS placement, and the secondary outcomes were relapse-free survival (RFS), recurrence, and short-term outcomes of SEMS placement and surgery. RESULTS: The 1-, 3-, and 5-year OS rates were 94.1%, 77.4%, and 67.4% (Kaplan-Meier), respectively, with high technical success (99.0%, 206/208) and low perforation (1.9%, 4/208) rates. The 1-, 3-, and 5-year RFS rates were 81.6%, 65.6%, and 57.9% (Kaplan-Meier), respectively, and the overall recurrence rate was 31.0% (62/200). The RFS rate was significantly poorer in patients with perforation (n = 4) than in those without perforation (n = 196) (log-rank P = 0.017); moreover, perforation was identified as an independent factor affecting RFS (hazard ratio 3.31; 95% confidence interval 1.03-10.71, multivariate Cox regression). CONCLUSION: This large, prospective, multicenter study revealed satisfactory long-term outcomes of BTS colonic stenting using a standardized SEMS insertion method, which might be specifically due to the reduced perforation rate. (UMIN000007953).

Functional Prognosis Following Temporal Bone Chondroblastoma Resection: A Systematic Review and Case Illustration.

BACKGROUND: Chondroblastomas are rare tumors that account for <1% of all bone tumors, and 5.7% of them occur in the skull. The aim of this study was to investigate factors related to their functional prognosis by conducting a systematic review, including our own case. METHODS: A systematic review was conducted of case reports that clearly stated postoperative symptoms in temporal chondroblastomas. Tumor localization was limited to cases of the temporal bone. Cases not described in English were excluded. RESULTS: We obtained 30 articles comprising 44 cases and included our own case for a total of 45 cases. Postoperative asymptomatic cases accounted for 53.3% (24/45), and symptomatic cases accounted for 46.7% (21/45). Complications were observed in 31.1% (14/45) of cases. The main complications were facial palsy (9 cases), occlusal disorders (4 cases), and hearing loss (4 cases). The occurrence of facial palsy as a complication was considered likely. Tumor size was confirmed in 36 cases. Cases with postoperative complications were more likely to involve tumors ≥5 cm in size (77.8%, 7/9) compared with cases without complications (40.7%, 11/27). There was a significant association between rate of postoperative complications and tumor size (P = 0.061). CONCLUSIONS: As temporal chondroblastoma poses a risk of residual postoperative symptoms when the tumor grows, aggressive surgical treatment should be considered even in asymptomatic or small tumors.

Enlargement of preexisting superficial temporal artery pseudo-aneurysm co-incidental to mask wearing during the Covid-19 pandemic.

The superficial temporal artery (STA) pseudo-aneurysm is usually associated with trauma. We report a unique case of an STA pseudo-aneurysm that developed due to mask wearing during the Covid-19 pandemic. A 70-year-old female presented with a 3-month history of a rapidly growing pseudo-aneurysm of the right STA. Over the past 3 months the patient had been wearing a mask for the prevention of Covid-19. The STA aneurysm was located exactly at a pressure point created by the rubber mask. Therefore, we assumed that an enlargement of the preexisting aneurysm had taken pace due to irritation from the elastic band of the mask. Surgical excision of the aneurysm and reconstruction of the STA using STA-STA bypass were performed. To our knowledge, we here report the first case of an STA pseudo-aneurysm that was potentially affected indirectly by the Covid-19 pandemic. Clinicians should be cautious about the preexisting medical condition that is potentially worsened by mask band compression.

Short-Term Outcomes of Colorectal Stenting Using a Low Axial Force Self-Expandable Metal Stent for Malignant Colorectal Obstruction: A Japanese Multicenter Prospective Study.

(1) Background: Endoscopic colorectal stenting with high technical success and safety is essential in discussing the oncological outcomes for the management of malignant colorectal obstruction. Mechanical properties of self-expandable metal stents are usually considered to affect clinical outcomes. (2) Methods: A multicenter, prospective study was conducted in Japan. A self-expandable metal stent with low axial force was inserted endoscopically. The primary endpoint was clinical success, defined as the resolution of symptoms and radiological findings within 24 h. Secondary endpoints were technical success and adverse events. Short-term outcomes of 7 days were evaluated in this study. (3) Results: Two hundred and five consecutive patients were enrolled. Three patients were excluded, and the remaining 202 patients were evaluated. The technical and clinical success rates were 97.5% and 96.0%, respectively. Major stent-related adverse events included stent migration (1.0%), insufficient stent expansion (0.5%), and stent occlusion (0.5%). No colonic perforation was observed. There were two fatal cases (1%) which were not related to stent placement. (4) Conclusions: The placement of self-expandable metal stents with low axial force is safe with no perforation and showed high technical and clinical success rates in short-term outcomes for the management of malignant colorectal obstruction.

Whole cancer-region enhancement using meglumine-gadopentetate-glucose solution and 7.0-T magnetic resonance imaging.

To visualize whole cancerous region including hypoxic cancer without radiation exposure, we developed meglumine-gadopentetate-glucose solution for 7.0-T magnetic resonance imaging. The infusion solution consists of meglumine-gadopentetate and glucose solutions, and these solutions are mixed before the vein drip infusion. We used readily available solutions, and the concentrations of the meglumine-gadopentetate and glucose solutions were 37.14 and 5.0%, respectively. In the first and second experiments, vein infusions were conducted from a rabbit ear using meglumine-gadopentetate-saline and meglumine-gadopentetate-glucose solutions, and T1 weighted imaging was performed to visualize cancerous region. Using the meglumine-gadopentetate saline, it was not difficult to image cancer-growth regions with new blood vessels. Using the meglumine-gadopentetate-glucose solution, the signal intensity of whole cancerous region including hypoxic cancer substantially increased. The visualizing duration for the meglumine gadopentetate glucose was beyond 90 min, and the rabbit survived after the infusion. The signal intensity in the hypoxic cancer was increasing until 90 min using the meglumine-gadopentetate-glucose solution, since the meglumine-gadopentetate molecules were absorbed into almost the whole cancerous region along with glucose-molecule flows.

Multicentric glioblastoma in a 4-year-old female patient: A case report.

In the USA and Germany, pediatric glioblastoma (pGBM) makes up <3% of childhood brain tumors. Occasionally, GBM has multiple contrast lesions and is referred to as multicentric GBM. The current study present a case of a four-year-old female patient presented with headache, vomiting and consciousness disturbance. Radiologically, a neoplastic lesion of the right frontal lobe with hemorrhage, and bilateral thalamus, right temporal and left occipital neoplastic lesions were identified. The right frontal lesion was not continuous to other lesions. It was concluded that the tumor was a multicentric GBM with intra-tumoral hemorrhage. The tumor was pathologically GBM. Following surgery, the patient underwent chemotherapy and radiotherapy, but 11 months after surgery, the patient passed away. This case had features of childhood GBM and multicentric GBM and was difficult to treat.

Ependymoma-like tumor with mesenchymal differentiation harboring C11orf95-NCOA1/2 or -RELA fusion: A hitherto unclassified tumor related to ependymoma.

Recurrent fusion genes involving C11orf95, C11orf95-RELA, have been identified only in supratentorial ependymomas among primary CNS tumors. Here, we report hitherto histopathologically unclassifiable high-grade tumors, under the tentative label of "ependymoma-like tumors with mesenchymal differentiation (ELTMDs)," harboring C11orf95-NCOA1/2 or -RELA fusion. We examined the clinicopathological and molecular features in five cases of ELTMDs. Except for one adult case (50 years old), all cases were in children ranging from 1 to 2.5 years old. All patients presented with a mass lesion in the cerebral hemisphere. Histologically, all cases demonstrated a similar histology with a mixture of components. The major components were embryonal-appearing components forming well-delineated tumor cell nests composed of small uniform cells with high proliferative activity, and spindle-cell mesenchymal components with a low- to high-grade sarcoma-like appearance. The embryonal-appearing components exhibited minimal ependymal differentiation including a characteristic EMA positivity and tubular structures, but histologically did not fit with ependymoma because they lacked perivascular pseudorosettes, a histological hallmark of ependymoma, formed well-delineated nests, and had diffuse and strong staining for CAM5.2. Molecular analysis identified C11orf95-NCOA1, -NCOA2, and -RELA in two, one, and two cases, respectively. t-distributed stochastic neighbor embedding analysis of DNA methylation data from two cases with C11orf95-NCOA1 or -NCOA2 and a reference set of 380 CNS tumors revealed that these two cases were clustered together and were distinct from all subgroups of ependymomas. In conclusion, although ELTMDs exhibited morphological and genetic associations with supratentorial ependymoma with C11orf95-RELA, they cannot be regarded as ependymoma. Further analyses of more cases are needed to clarify their differences and similarities.