Yoshimune Horibe

Irrigation Volume Determines the Efficacy of “Rectal Washout”

PURPOSERectal stump washout has been recommended to prevent implantation of exfoliated malignant cells in the anastomosis after anterior resection for rectal cancer. The aim of this study was to investigate its efficacy, particularly the extent to which the volume of irrigation fluid might influence the efficacy of tumor cell elimination and whether tumor characteristics might influence the result.METHODSThe study comprised 30 consecutive patients operated on by anterior resection for rectal cancer. After cross-clamping the rectum below the tumor, a washout sample was collected for examination after every incremental 500 ml of saline irrigation up to 2 liters. The presence of shed cancer cells was correlated with the washout volume and tumor characteristics.RESULTSCancer cells were found in 29 of 30 patients (97 percent) in the first sample of irrigation fluid and decreased gradually in frequency and number with increasing irrigation volumes. No cancer cells were demonstrated after 1.5 liters of irrigation in patients with tumor below the peritoneal reflection, whereas cancer cells were still present in one-fourth of the patients with tumor located above the peritoneal reflection. Finally, only a small number of cancer cells was confirmed in one patient after 2 liters of irrigation.CONCLUSIONSThe irrigation volume determined the efficacy of rectal washout. With our method, 1 1/2 liters of saline irrigation appears to clear contents from cancer cells in patients with tumors below the peritoneal reflection whereas at least 2 liters is recommended for patients with tumor above the peritoneal reflection.

Epithelial inclusion cyst (epidermoid cyst) formation with epithelioid cell granuloma in an intrapancreatic accessory spleen

The histologic characteristics of a case of epidermoid cyst formation with an epithelioid cell granuloma that developed in intrapancreatic accessory spleen were investigated, with the aim of clarifying its origin as well as etiologic factors. The patient, a 48‐year‐old male, was found to have a cystic lesion in the tail of the pancreas and renal cell carcinoma (clear cell carcinoma) during a medical check up. The pancreatic mass appeared to be a so‐called ‘mucinous tumor’ on imaging, and combined resection of the body and tail of the pancreas and the spleen was performed together with a left nephrectomy. The lesion in the tail of the pancreas was then demonstrated to have accessory splenic tissue with cyst formation in its central region. The cystic wall was covered with stratified squamous epithelium and ductal epithelium with squamous metaplasia, and pancreatic islet cells were evident at various sites within the accessory spleen. Formation of epithelioid cell granuloma tissue was observed around the cysts. The epithelium of the cyst was positive for CA19‐9 and negative for antibodies against mesothelial cells, whereas the pancreatic island cells were positive for insulin. These results suggested that cystic epithelium in the accessory spleen could be derived from pancreatic duct epithelium. Frequent recurrence of chronic inflammation and epitheloid cell granuloma formation may have resulted from an aberration of the ectopic remaining pancreatic tissue in the spleen.

Primary primitive neuroectodermal tumor of the kidney

Primitive neuroectodermal tumor (PNET) is a small round cell sarcoma that mainly develops in the central nervous system and soft tissues of childhood; however recently, primary occurrence of this tumor in the kidney has been reported. We experienced one case of PNET primarily arose in the kidney without metastasis. The patient was a 28‐year‐old man whose chief complaint was abdominal pain, especially on exercise. On computed tomography scan and magnetic resonance imaging, a solid lesion was found in the left kidney, and a left nephrectomy was performed based on the diagnosis of a tumor in the left kidney. The tumor was within the parenchyma of lower end of left kidney protruding into the abdominal cavity. Histologically, diffuse proliferation of primitive small round cells with rosette formation was found. Immunohistochemically, MIC2 gene product, neuron‐specific enolase and S‐100 protein were positive. No metastasis to the regional lymph nodes was found. From these observations, the tumor was diagnosed as PNET primarily arising in the left kidney. Although chromosome analysis was not performed, EWS‐FLI1 chimera gene was identified by reverse transcriptase–polymerase chain reaction on the freshly frozen specimen and fluorescence in situ hybridization on paraffin sections.

Acrosyringium Is the Main Site of the Vesicle/Pustule Formation in Palmoplantar Pustulosis

Pustulosis palmaris et plantaris or palmoplantar pustulosis (PPP) is a refractory pustular eruption on the palms and soles with unknown etiology. Numerous eccrine sweat pores exist on the palms and soles, suggesting the involvement of eccrine sweating in the pathogenesis of PPP. To the best of our knowledge, however, no definite abnormality in sweating has been documented in PPP. Accordingly, we analyzed the eccrine sweat duct involvement in the mechanism of vesicle formation in PPP. Dermatoscopy showed that PPP vesicles are located on the top of the ridges but not in the furrows. The sweat secretion in the lesional area was much lower than that in the nonlesional area, with or without pain stimulation to induce sweating. Immunostaining of horizontal sections of the lesions using antibodies against gross cystic disease fluid protein-15 (GCDFP-15) and epithelial membrane antigen (EMA) showed that these markers were localized in the cells lining the intraepidermal vesicles. Although the sweat antimicrobial peptides, dermcidin and human cathelicidin antimicrobial peptide 18 (hCAP-18)/LL-37, were detected in the fluid of the vesicles/pustules, neither dermcidin nor hCAP-18/LL-37 were overexpressed by neighboring keratinocytes. These findings suggest that the acrosyringium may be involved as the main site of the vesicle formation in the pathomechanism of PPP.

Sclerosing mucoepidermoid carcinoma with eosinophilia of the salivary glands

We encountered two cases of low malignant mucoepidermoid carcinoma with scanty cellular atypism which originated in the parotid or submandibular gland and was characterized by marked fibrosis and eosinophilic infiltration within tumor tissue despite the predominance of the squamous component. Here we report these two cases and provide a review of the literature. We believe that clinically these two tumors with stromal fibrosis and eosinophilic infiltration have a low malignant potential, although histological examination revealed a scanty mucus-producing epithelial component. Therefore, we consider this type of tumor as a new subtype of mucoepidermoid carcinoma. A low-malignant mucoepidermoid carcinoma with stromal fibrosis and eosinophilic infiltration, as described in these two cases, may be misdiagnosed as a highly malignant mucoepidermoid carcinoma or squamous cell carcinoma because of its histologically scanty mucus-producing epithelial component. The objective of this study was to clarify their differences and to discuss the rendering of an accurate histological diagnosis, the degree of malignancy in relation to prognosis prediction, and the choice of therapy. In addition, we propose regarding this type of tumor as a new subtype of mucoepidermoid carcinoma.

Warthin-like tumor variant of papillary thyroid carcinoma: Case report and literature review

A tumor approximately 4.0 × 3.0 cm in size with a cystic change was observed in the left lobe of the thyroid gland of a 52‐year‐old woman. The removed tumor had lymph follicle formation with a germinal center. This lymphatic tissue showed papillary and island‐like growth; the growths were surrounded by atypical epithelium showing nuclear features of papillary carcinoma. The atypical epithelium had ground‐glass nuclei with nuclear grooves, clearly indicating intranuclear cytoplasmic inclusion bodies. No chronic thyroiditis was observed in the background of the patient. Parts of the metastatic lymph nodes had cells with an eosinophilic cytoplasm, clearly showing an intratumor lymph follicle formation, as in the primary lesion. This is a rare case of thyroid papillary carcinoma similar to Warthins tumor of the salivary gland. Here we present this case, with a review of previously published reports.

A patient with early gallbladder cancer derived from a Rokitanski-Aschoff sinus

We present herein a case of a 40-year-old male with early gallbladder cancer derived from a Rokitanski-Aschoff sinus (RAS). The patient originally presented at our hospital with epigastric discomfort, following which a diagnosis of adenomyomatosis (ADM) of the gallbladder was made, and a cholecystectomy performed. Histopathological examination of the resected specimen revealed a 7-mm well-differentiated papillo-tubular adenocarcinoma in the RAS epithelium in the body of the gallbladder. The RAS extended to the “pm” layer but the adenocarcinoma was an in situ lesion localized within the RAS epithelium. Considering the difficulties in making an early diagnosis of gallbladder cancer, active surgery should be performed for patients in whom ADM is seen in the gallbladder.

Does perifascial rectal excision (i.e. TME) when combined with the autonomic nerve‐sparing technique interfere with operative radicality?

Objective  The lymphatic drainage from the rectum was studied to evaluate if the autonomic nerve sparing dissection may interfere with the operative radicality and might result in metastatic lymph nodes being overlooked and left in situ.

Expression of topoisomerase II alpha, Ki-67 and p53 in early stage laryngeal carcinomas not featuring vocal cord fixation.

Aim. To determine whether topoisomerase II alpha (topolla) expression is an additional prognostic marker for less advanced stage laryngeal cancers first treated without surgery. Ki‐67 and p53 protein levels were also assessed for comparison. Experimental design. Formalin‐fixed, paraffin‐embedded tumor material from 63 cases of squamous cell carcinoma (SCC) of the larynx (glottis, stages 0,1,2) was immunohistochemically stained for topolla, Ki‐67 (MIB‐1) and p53 (DO‐7) and the results were compared with clinicopathologic findings. Results. There were 7 stage 0 (TisNOMO), 33 stage I (T1N0M0), and 23 stage II (T2N0M0) SCCs with the TNM classification. Significant differences between carcinomas and normal mucosa were found for the topoIIa‐LI, Ki‐67‐LI, and topolla‐to‐Ki‐67 ratio. Regarding histologic grade, a significant difference in topoIIa‐to‐Ki‐67 ratio was evident between well or moderately and poorly differentiated lesions. There were 19 cases of recurrence and 44 cases of nonrecurrence, but no significant differences were found for either of the indices or their ratio. No significant variation with p53 positivity was evident with reference to histologic differentiation, T‐factor, clinical course, or proliferation. Conclusions. The results demonstrate that the topoIIa‐to‐Ki‐67 ratio is a more sensitive parameter reflecting proliferation, for histologic grading of less advanced laryngeal SCCs, than topolla‐ or Ki‐67‐LIs.

In situ localization of S-phase-specific histone (H3) mRNA in Bowen's disease.

PCNA and Ki‐67 immunohistochemistry has been used to assess cell proliferation in place of tritiated thymidine or BrdU labeling of S‐phase cells. Recently, it has been possible to reliably demonstrate histone H3 mRNA by in situ hybridization in formalin‐fixed and paraffin‐embedded tissue sections. We have compared this new proliferation marker with Ki‐67 and PCNA with regard to distribution of positive cells and labeling indices (LI%) for 22 cases of Bowens disease.