Akira Arasaki

INTRAOPERATIVE RADIATION THERAPY (IORT) FOR HEAD AND NECK CANCER

PURPOSE To determine the efficacy of intraoperative radiation therapy (IORT) for patients with advanced or recurrent head and neck cancer. METHODS AND MATERIALS Intraoperative radiation therapy was given at 30 sites in 25 patients using a 6-18 MeV electron beam with or without conventional external beam irradiation. A single dose of 10-30 Gy was delivered after surgical resection. Sites treated with IORT were classified into three types after surgical resection: gross residual disease (GR, n = 7), microscopic residual disease (MR, n = 12), and close margin (CM, n = 11). Local control rate, patterns of recurrence, survival rate, and complications were analyzed. RESULTS The 2-year cumulative local control rate within the IORT port was 54.1% for all cases, 0% for GR, 54.5% for MR, and 81.8% for CM. There were significant differences between GR and MR (p < 0.05), and GR and CM (p < 0.01). The majority of the failures inside the IORT port were associated with recurrence outside the port. Distant metastases occurred in five patients. Four of these had GR. The 2-year cumulative survival rate was 45.1% for all, 0% for GR, 33.0% for MR, and 70.0% for CM. Five patients (22%) experienced late complications. The 2-year cumulative complication rate was 32.8%. Four sites developed osteoradionecrosis and three developed carotid artery blowout. Incidence of complications increased when patients received over 20 Gy with a single dose of IORT. CONCLUSIONS Considering both therapeutic ratio and patterns of failure, it is not suitable to treat patients with gross residual disease with IORT. We could not firmly determine the therapeutic value of IORT for patients with microscopic residual disease and close margin. For this subset, further study of moderate dose (less than 20 Gy) IORT combined with adequate postoperative irradiation is needed.

Epstein–Barr virus (EBV)-related oral squamous cell carcinoma in Okinawa, a subtropical island, in southern Japan—simultaneously infected with human papillomavirus (HPV)

Up to now, many authors have reported on the EBV infection and its carcinogenic importance in undifferentiated nasopharyngeal carcinoma (WHO classification, type III), but the infection of the virus in well differentiated oral squamous cell carcinoma has not been well described. We introduce the EBV-related well differentiated oral squamous cell carcinomas in Okinawa, a subtropical island in the southernmost part of Japan. This study aimed to clarify the pathogenesis of this malignancy in this area by carrying out analysis of the histology and the Epstein-Barr (EBV) and human papillomavirus (HPV) infection. In the Department of Oral Surgery, Ryukyu University Hospital Okinawa, 188 cases of oral malignant tumours were encountered from 1996 to 2000. The histopathological examination and the sequence analysis of LMP-1 carboxy terminal region and EBNA2 region of EBV were carried out, as were the analysis of virus subtypes, A and B, BamHI-F and f, and C and D. Additionally, HPV infection in the squamous cell carcinomas were demonstrated using E6 and E7 region primer sets by PCR method. In Okinawa, 94% (177/188) of the cases were squamous cell carcinomas. A surprisingly large number of EBV (72%) and HPV (78%) infections in the oral squamous cell carcinomas were demonstrated. EBV type B virus infection was found in 36% of EBV-related oral squamous cell carcinoma in Okinawa, but in only 2-5% of the mainland cases. In both regions the incidence of the BamHI- f variant infection was very low. The infected virus in 79 out of 80 (39 Okinawan and 41 mainland) cases was BamHI- F type. In Okinawa, the numbers of C and D variants were almost equal, whereas in the mainland the D variant was rare. Further, a 30 bp deletion in LMP-1 gene was frequently demonstrated in Okinawan and mainland cases of type A virus, but not in type B virus. Lastly, single nucleotide mutations in EBNA2 region of type A virus when compared with B95-8 strain were demonstrated in Okinawan cases. The prognosis for (mostly EBV/HPV infected) squamous cell carcinomas in Okinawa was better than that in the mainland where most cases were negative for EBV and/or HPV.

Morules in endometrial carcinoma and benign endometrial lesions differ from squamous differentiation tissue and are not infected with human papillomavirus

Background: Squamous differentiation/squamous metaplasia is often associated with endometrial adenocarcinoma and benign lesions, such as endometrial hyperplasia and chronic endometritis. Morules have distinct histological characteristics, and are referred to as squamous metaplasia or squamoid metaplasia. Aim: To focus on the histological characteristics of morules and clarify the difference between morules and squamous differentiation. Materials/Methods: Twenty endometrioid carcinomas with morules or squamous differentiation, five adenosquamous carcinomas, and eight non-carcinomatous endometrial lesions with morules were investigated. Numerous antibodies for epithelial membrane antigen (EMA), involucrin, cytokeratins, neuropeptides, and oncofetal antigens were used for immunohistochemistry. In situ hybridisation and polymerase chain reaction were used to detect human papillomavirus (HPV). Results: The morules observed were uniform cell clusters, with no squamous differentiation. They were immunonegative for epithelial antigens including involucrin, EMA, and cytokeratins, but were positive for neurone specific enolase. A few morules were immunopositive for acetylcholine esterase, and one case was positive for somatostatin; neither oncofetal nor proliferative cell markers, including blood group A, B, and AB, or other neuropeptides were demonstrated in the morules. HPV DNA was not found in either the morules in the carcinomas or in the benign lesions. However, true squamous differentiation tissue in four endometrioid carcinomas and two adenosquamous carcinomas was HPV positive using in situ hybridisation. Conclusion: Morules are histologically distinct from squamous metaplasia/squamous differentiation tissue. Morules are thought to be neuroectodermal-like cell clusters, and are not infected with HPV. In contrast, some of the true squamous differentiation tissue was associated with HPV infection.

RETRACTED: Downregulation of citrin, a mitochondrial AGC, is associated with apoptosis of hepatocytes

Citrin is a mitochondrial aspartate-glutamate carrier primarily expressed in liver. Adult-onset type II citrullinemia is caused by mutations in the SLC25A13 gene that encodes for citrin, and patients with this condition do not express citrin. We found apoptotic hepatocytes in one such patient. This finding prompted us to investigate the role of citrin in hepatocyte survival. Knockdown of citrin by a vector-based short-hairpin RNA technique reduced cell viability and induced apoptosis of a hepatocellular carcinoma cell line, Hep3B cells. Caspase-3/7 and caspase-9 were activated, and PARP was cleaved. Citrin knockdown also increased the expression of Bax and Bak, and reduced expression of Bcl-xL and Bcl-2. These alterations resulted in the release of cytochrome c from the mitochondria. Our results indicated that citrin downregulation induces apoptosis of hepatocytes through the mitochondrial death pathway, highlighting the importance of citrin in survival of hepatocytes and maintenance of liver function.

PDGF α receptor is a mediator for Cisplatin-induced Met expression.

For decades, platinum drugs have been the mainstay of cancer treatment. However, over time, drug resistance develops, leaving few treatment options. Here we show that platelet-derived growth factor α receptor (PDGF α receptor)-mediated signaling plays a key role in hepatocyte growth factor (HGF) receptor (c-Met) upregulation, which in turn is thought to play an important role in chemotherapy resistance. PDGF α receptor inhibition eliminates cisplatin-dependent Met expression in cervical cancer cell lines. PDGF α receptor inhibitors are widely used in clinical settings, suggesting that the clinical translation of our findings could reduce the suffering of people from drug resistance.

HPV16E6-Dependent c-Fos Expression Contributes to AP-1 Complex Formation in SiHa Cells

To date, the major role of HPV16E6 in cancer has been considered to be its ability to inhibit the p53 tumor-suppressor protein, thereby thwarting p53-mediated cytotoxic responses to cellular stress signals. Here, we show that HPV16E6-dependent c-fos oncogenic protein expression contributes to AP-1 complex formation under oxidative stress in SiHa cells (HPV16-positive squamous cell carcinoma of the cervix). In addition, we examined the role of HPV16E6 in TGF-α-induced c-fos expression and found that the c-fos protein expression induced by TGF-α is HPV16E6 dependent. Thus, our results provide the first evidence that HPV16E6 contributes to AP-1 complex formation after both ligand-dependent and independent EGFR activation, suggesting a new therapeutic approach to the treatment of HPV-associated tumors.

Outcomes of an International Volunteer Surgical Project for Patients with Cleft Lip and/or Cleft Palate: A Mission in Developing Laos

Cleft lip and/or palate (CL/P) is a common birth defect of complex etiology. CL/P surgery is generally performed in infancy to allow for improvements in esthetics, suckling, and speech disorders as quickly as possible. We have engaged in activities such as free‐of‐charge surgery for CL/P a total of 12 times from 2001 to 2016 in Lao Peoples Democratic Republic (Laos). The United Nations has designated Laos as a Least Developed Country; it is one of the poorest countries in Asia. We have carried out our activities for a long time, primarily in CL/P patients who cannot undergo surgery for financial reasons, and we have performed CL/P‐related surgeries for 283 patients up to 2016. When we began our activities in 2001, the mean age at first cheiloplasty was 11.6 years, which dropped over time until 2016 when the mean age was 1.8 years. A linear regression analysis showed a significant difference between the age at first lip plasty and the year of first operation (β = −0.35; P < 0.001). This was likely an effect of continuing to train local medical staff in surgical techniques and donating surgical tools and facilities over a period of 16 years while building a good relationship with local staff. However, the healthcare system in Laos is an obstacle to some patients who still cannot undergo CL/P surgery in infancy for financial reasons. We therefore need to support Laos to provide treatment on their own as we continue to carry out our activities for CL/P patients.

Indolent growth of low-grade myofibroblastic sarcoma of the cheek mimics benign lesions: A case report and literature review

Low-grade myofibroblastic sarcoma (LGMS) is a neoplasm of the soft tissue characterized by myofibroblastic differentiation. This type of tumor has been observed in various sites in the whole body, but frequently occurs in the head and neck region. It typically presents as a slow-growing painless mass, which is often mistaken for a benign lesion due to its indolent growth; however, LGMS is a malignant neoplasm. In the present study, a 43-year-old female presented with a 14-mm LGMS lesion in the buccal subcutaneous tissues of the buccinator muscle. The patient had initially noticed the lesion 2-months prior to presenting at the hospital. Following biopsy, the tumor was surgically resected and no recurrence or metastasis was observed during a follow-up time of 2 years. To the best of our knowledge, this case is the first report of LGMS located in the buccal subcutaneous tissue of the buccinator muscle. The present study a literature review of 55 cases of this tumor type in the head and neck region was conducted, revealing that the indolent growth of these lesions may contribute to a delay in diagnosis. The average time between the onset of clinical symptoms and hospital admission is 3.9 months, and this form of tumor is frequently misdiagnosed as a benign lesion. Therefore, the present study suggests that an incisional biopsy may be performed to rule out LGMS when clinicians encounter patients with the aforementioned indolent lesions anywhere in the body. In addition, the avoidance of radiotherapy is recommended following resection of the LGMS tumor, as it may induce LGMS recurrence.

Malignant Pheochromocytoma with Mandibular Metastasis

Abstract Malignant pheochromocytoma of the mandible is an extremely uncommon tumour. This report describes a 59-year-old woman with pheochromocytoma metastatic to the mandible. The patient was referred with a painless mandibular swelling on the right side. She had undergone dual tumour ablation for a pheochromocytoma of the adrenal medulla 7 years and 6 months previously, and for a pheochromocytoma metastatic lesion on the pelvis 2 years and 8 months previously. Radiographic examinations revealed a well-circumscribed radiolucent lesion of the mandibular ramus. A definitive diagnosis of malignant pheochromocytoma was made following a partial mandibulectomy. The patient died of disseminated intravascular coagulation and multiple bone metastases of pheochromocytoma about 10 years after the initial diagnosis of disease.

Triple primary malignancies of surface osteosarcoma of jaw, myelodysplastic syndrome and colorectal cancer as a second primary cancer detected by PET2‑[18F]‑fluoro‑2‑deoxy‑D‑glucose positron emission tomography: A case report

Second primary malignancy (SPM) is a severe issue for cancer survivors, particularly for osteosarcoma (OS) survivors. To date, the associations between subsequent SPM and OS have been well reported. Hematogenic and solid malignancies tend to occur following OS treatment. Reportedly, 2-[18F]-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) is mainly used in OS patients for initial cancer staging, to evaluate the response of neoadjuvant chemotherapy, and when recurrence or metastasis is clinically suspected. The present case report describes a 70-year-old man diagnosed with three primary malignancies: jaw OS, myelodysplastic syndrome and colorectal adenocarcinoma. To the best of our knowledge, this combination of malignancies has not been reported previously. Until now, there is no specific protocol of postoperative FDG-PET for OS patients. Few studies have described OS follow-up methods; therefore, there is no consensus on proper follow-up methods. In the present case report, the colorectal early-stage SPM was observed, without any symptoms, by FDG-PET/computed tomography. To avoid overlooking solid SPMs, it is suggested that FDG-PET should be performed in the long-term follow-up of OS patients.