Tetsuro Onitsuka

Comparison of innervated and noninnervated free flaps in oral reconstruction.

Thirteen patients who had undergone ablative surgery for advanced squamous cell carcinoma in which more than half of the tongue had been resected underwent reconstruction in which the cutaneous nerve of a free flap was anastomosed to the stump of the transected lingual nerve. Eight of the patients underwent reconstruction with an innervated anterolateral thigh flap and five patients underwent reconstruction with an innervated rectus abdominis musculocutaneous flap. Sensory recovery of the flap at least 6 months postoperatively was compared in these 13 patients and in 16 additional patients who received noninnervated versions of the same flaps for the same defect. The degree of sensory recovery of innervated thigh flaps was significantly greater than that of noninnervated ones in all modalities and that of innervated rectus abdominis flaps was also greater than that of noninnervated flaps, except for hot and cold perception. These results indicate that sensory regrowth occurs in most areas through the surgically created pathways. However, results of Semmes-Weinstein testing showed that recovery did not reach the level of protective sensation in either type of innervated flap. Although these findings must be followed by additional objective and functional tests and the need for sensory reeducation should be considered, this simple operative procedure can improve postoperative intraoral function and should be attempted whenever possible after ablative surgery.

Dedifferentiated epithelial-myoepithelial carcinoma of the parotid gland: a rare case report of immunohistochemical analysis and review of the literature

Dedifferentiation of salivary gland neoplasms is a rare event, unlike bone and soft part sarcomas, which was first described by Stanley et al. in 1988. An additional case of dedifferentiated epithelial-myoepithelial carcinoma (EMC) is reported here. The patient was a 70-year-old Japanese man who requested examination of the rapid growth of a mass in the right parotid region, which he had first noticed 25 years previously. Clinical examination showed an ill-circumscribed, 6.8 x 4.7 x 7.0-cm lesion. Histologically, most parts of the lesion were high-grade carcinoma (HGC) with sheetlike and nestlike growth of markedly atypical cells and comedonecrosis, whereas the minor part consisted of typical EMC. The outer clear cells of EMC were positive for alpha-smooth muscle actin (ASMA), p63, cytokeratin (CK) 14, and vimentin, and the inner ductal cells of EMC were positive for CKs and epithelial membrane antigen. HGC was negative for ASMA, CK14, and vimentin, but diffusely positive for p53 protein and cyclin D1. The Ki-67 labeling index of EMC was 11.5%, whereas that of HGC was 67.1%. These findings and a review of literature indicate that HGC arose from preexisting EMC, and this phenomenon is the dedifferentiation of EMC. Dedifferentiated EMC is extremely rare.

Mucosal large cell neuroendocrine carcinoma of the head and neck regions in Japanese patients: a distinct clinicopathological entity

Backgrounds Large cell neuroendocrine carcinoma (LCNEC) is well-known as a lung cancer subtype. This study assessed the prevalence of head and neck mucosal LCNEC (M-LCNEC). Methods M-LCNEC was studied clinically, histologically and immunohistochemically. Results Of 814 surgically resected cases of mucosal head and neck carcinoma, only eight cases (0.98%; all men, mean age 64.6 years) were rediagnosed as M-LCNEC. They occurred in the oropharynx (n=3), larynx (n=4) and hypopharynx (n=1). Seven of the cases had regional lymph node metastases and four resulted in death. Histologically, M-LCNEC had a sheet-like trabacular organoid growth pattern of relatively large basaloid cells in which central necrosis, rosette formation, peripheral palisading and high mitotic figures were evident. M-LCNEC was immunopositive for two or three neuroendocrine markers (CD56, chromogranin-A and synaptophysin). All cases showed high proliferative activity. Conclusion M-LCNEC in the head and neck regions is a distinct histopathological entity whose positivity for neuroendocrine markers makes its diagnosis important. As about half of the patients died of the disease, M-LCNEC has a relatively poor prognosis.

Mandible reconstruction using the calcium-sulphate three-dimensional model and rubber stick: A new method, ‘mould technique’, for more accurate, efficient and simplified fabrication

BACKGROUND Osteocutaneous flaps are one of the best options for one-stage mandible reconstruction. However, the challenge remains to achieve optimal functional and cosmetic results. A new novel approach involving the preoperative prefabrication of a reconstructive plate through a calcium-sulphate three-dimensional (3D) model facilitates the contouring of vascularised bone grafts. We herein report our preparations and results using this technique. METHODS A total of 17 mandibular defects were reconstructed by this novel approach. A calcium-sulphate 3D model was constructed from computed tomography (CT) data. After the oncologist designed the cut line on the model, the mandibular arc was ground to the neo-mandible shape, which consisted of several linear planes according to the osteotomy of the bone graft. The reconstruction plate was shaped to fit this. After tumour resection, the prefabricated plate was placed to the remaining mandible and revealed the defect to be reconstructed, just as a mould. Rubber sticks were used as a template to shape the bone graft. The preoperative information, and functional and aesthetic results were retrospectively analysed. RESULTS As many as 12 fibular and 5 scapular flaps were applied. Postoperative complications included two salivary fistulae, one abscess and one partial skin loss, all of which were resolved after conservative treatment. Postoperatively, all patients could speak clearly, 12 had a normal diet and 12 had excellent cosmetic results. CONCLUSIONS This is the first report using models made by calcium-sulphate. The largest advantage of this model is that the neo-mandible shape can be demonstrated preoperatively. The refinement of mandible reconstruction after tumour ablative surgery can be achieved with a prefabricated plate through the use of a calcium-sulphate 3D model. It enables more accurate, faster and simplified fabrication of reconstruction plates, thus leading to satisfactory functional and cosmetic results.

Primary adenoid squamous cell carcinoma of the oral cavity

Adenoid squamous cell carcinoma (ASCC) is an uncommon but well‐recognized variant of squamous cell carcinoma that was first described by Lever in 1947. ASCC has been reported to originate in the sun‐exposed skin of the head and neck and in other sites. An additional case of ASCC is reported here. The patient was a 64‐year‐old Japanese woman who requested examination of a reddish lesion on the left floor of the mouth. The biopsy material was diagnosed as squamous cell carcinoma. Clinical examination showed a well‐circumscribed, 20 × 10 mm‐sized lesion, which was categorized as cT2cN0cm 0. Tumor resection was therefore performed. Histologically, most parts of the lesion were conventional squamous cell carcinoma in situ, but the invasive part consisted of ASCC with gland‐like or reticular appearance. The latter part was negative for mucin staining. Immunohistochemically, this lesion was positive for pancytokeratin, high‐molecular‐weight keratin, cytokeratin (CK) 7/8, CK19, E‐cadherin and p53, but negative for vimentin, CK20, and S‐100 protein. The Ki‐67 labeling index was 50.3% in the ASCC part and 34.5% in the carcinoma in situ part. These findings and a review of the literature indicate that a gland‐like feature of ASCC is associated with the loss of cell adhesion in the center of the cancer nests, and it can be confirmed simply by mucin staining to be neither an adenosquamous carcinoma nor ductal involvement of conventional squamous cell carcinoma.

Primary nasopharyngeal mucoepidermoid carcinoma in Japanese patients: two case reports with histochemical and immunohistochemical analysis and a review of the literature.

Mucoepidermoid carcinoma is a common neoplasm of the salivary glands. Salivary gland-type neoplasms are very rare in the nasopharynx, and there are only few reports on mucoepidermoid carcinoma of the nasopharynx. Two additional cases of mucoepidermoid carcinoma arising from the nasopharynx are reported here. Case 1: the patient was a 57-year-old Japanese woman who had bloody sputum. Case 2: the patient was a 51-year-old Japanese woman who underwent resection of a nasopharyngeal tumor. Histologically, both tumors were also low-grade mucoepidermoid carcinomas with clear cells. Histochemically, the gland-like nests and mucous cells were positive for mucin staining. Immunohistochemically, the lesions were positive for cytokeratins (CKs), p63, and MUC1, but negative for alpha-smooth muscle actin and EBER mRNA. The Ki-67 labeling indices of the two tumors were 10.4% and 4.3%, respectively. The two present cases and a review of the English literature indicate that salivary gland-type neoplasms arising from the nasopahrynx are extremely rare. The prognosis of salivary gland-type carcinomas of the nasopharynx is still unknown.

Sex Hormones in Papillary Carcinoma of Thyroid Gland and Pleomorphic Adenoma of Parotid Gland

This is a histologic study using the peroxidase-antiperoxidase (PAP) method for demonstration of estradiol, testosterone, dihydrotestosterone and progesterone in the normal thyroid gland and papillary carcinoma of the thyroid gland as well as in the normal parotid gland and pleomorphic adenomas. The results show that the normal follicular epithelia of the thyroid gland and the intercalated, striated ducts in the parotid gland stained for sex hormones. Estradiol was positive in both thyroid and parotid gland tissue in females and males. In females, testosterone and dihydrotestosterone were not recognized in the thyroid gland tissue and were only weakly present or negative in parotid gland tissue. In males, both testosterone and dihydrotestosterone were positive. Papillary carcinoma of the thyroid gland and pleomorphic adenoma of the parotid gland were positive for estradiol but not for testosterone or dihydrotestosterone. This suggests that there is a sex difference in the influence of sex hormones on the normal thyroid and parotid glands, and that estradiol exerts an influence on papillary carcinoma of the thyroid gland and pleomorphic adenoma of the parotid gland.

Effect of local extension sites on survival in locally advanced maxillary sinus cancer.

We analyzed the effects of local extension sites on survival in patients with locally advanced maxillary sinus cancer.

MYB, MYBL1, MYBL2 and NFIB gene alterations and MYC overexpression in salivary gland adenoid cystic carcinoma

Adenoid cystic carcinoma (AdCC) is one of the most common salivary gland malignancies and the long‐term prognosis is poor. In this study, we examined alterations of AdCC‐associated genes, MYB, MYBL1, MYBL2 and NFIB, and their target molecules, including MYC. The results were correlated to clinicopathological profile of the patients.

Salivary duct carcinoma with rhabdoid features: Report of 2 cases with immunohistochemical and ultrastructural analyses

Salivary duct carcinoma with rhabdoid features is extremely rare.