Emergence of higher levels of invasive and metastatic properties in the drug resistant cancer cell lines after the repeated administration of cisplatin in tumor-bearing mice

To establish a more suitable model for reflecting biological aggressiveness in clinically recurrent cancers after chemotherapy, we made the in-vitro-established cisplatin-resistant cell lines, by exposing the parental tumor cell lines to cisplatin in a culture system, and also the in-vivo-established cisplatin-resistant cell lines by repeated cisplatin administration to parental tumor-bearing mice. Although both cell lines similarly demonstrated a clinically relevant low level of drug resistance (from 1.5 to 2.9 times more resistance to cisplatin than their parental cell lines), only the in-vivo-established cisplatin-resistant cell lines showed significantly enhanced metastatic properties with a 2.1- to 3.4-fold increase in the number of lung metastatic nodules. These enhanced metastatic properties were caused by tumor invasiveness in combination with various levels of enhancement of cell attachment, proteolytic enzyme activity and cell motility. We concluded that anticancer drugs such as cisplatin could promote tumor progression only in the drug-resistant cell lines established in vivo. As a result, these cell lines are considered to be a more faithful and useful model for expressing biological aggressiveness in clinically recurrent cancers after chemotherapy than the conventional drug-resistant cell lines established in vitro.

Identification of persistent trophoblastic diseases based on a human chorionic gonadotropin regression curve by means of a stepwise piecewise linear regression analysis after the evacuation of uneventful moles

Among the 191 patients with complete hydatidiform moles who were diagnosed and treated at Kyushu University Hospital from 1982 until 1996, 167 patients were diagnosed with uneventful moles retrospectively. The serial beta human chorionic gonadotropin (hCG) values in the 167 patients with uneventful moles were analyzed by a stepwise piecewise linear regression analysis in order to establish a normal regression curve of a human chorionic gonadotropin after a molar pregnancy. This normal regression curve is considered to be excellent regarding sensitivity (24/24-100%) and to be equivalent to the identification based on a plateau or a rise regarding specificity (156/167-93.4%). To distinguish patients with persistent trophoblastic disease (PTD) from uneventful moles, this normal curve is thus considered to be accurate since the accuracy was 180/191 (94. 2%). The weeks exceeding the normal regression curve in 24 PTD patients were 5.04 +/- 3.85 weeks and were also earlier than the weeks based on a plateau or a rise (P = 0.01). Within 7 weeks after evacuation, in 21/24 (87.5%) of the PTD cases, the beta-hCG values exceeded the normal range, while in only 14/24 (58.3%) the beta-hCG showed a change in the shape of a plateau or a rise. In addition, in 19/24 (79.2%) of the PTD patients, the time exceeding the normal range was shorter than the time exhibiting a plateau or a rise in the beta-hCG change. The above findings thus led us to conclude that this normal regression curve was useful for discriminating PTD from uneventful moles more precisely and more quickly than by identification based on a plateau or a rise.

Development and histologic characteristics of synovitis induced by trauma in the rat temporomandibular joint

Histopathological changes caused by trauma to the rat temporomandibular joint synovium were examined by light microscopy. The trauma was induced by forced hypermobility of the condyle. Pathological changes of the synovium were found primarily in the anterior pouch of the upper joint compartment. The main findings included surface cell proliferation, increased capillary hyperemia, fibrin deposits on the surfaces of inflamed synovial membranes, and fibrinous adhesion between closely opposed synovial membranes. A gradual change from fibrinous adhesion to fibrous adhesion was also seen.

Angiogenesis in adenocarcinoma of the uterine cervix

BACKGROUND

Angiogenesis is essential for tumor growth, progression, and metastases. Microvessel density (MVD), a measure of tumor angiogenesis, has been found to have prognostic significance in many tumor types for predicting metastasis and survival.

METHODS

Between 1979-1989, 56 cases of FIGO Clinical Stage I and II adenocarcinoma of the uterine cervix treated by hysterectomy were reviewed histologically. All hysterectomy specimens were stained immunohistologically for factor VIII-related antigen. MVD was counted in a x200 field (0.785 mm2 per field) in the most active area of neovascularization. Results were expressed as the highest number of microvessels identified within any single x200 field. MVD and several other prognostic parameters were examined for correlation with progression free survival (PFS) and overall survival (OS) by a multivariate analysis according to the Cox proportional hazards model.

RESULTS

In early adenocarcinoma of the uterine cervix, MVD was increased significantly in invasive areas compared with adjacent nonneoplastic areas (median: 62.5 [range, 30-105] vs. median: 36.5 [range, 23-47]; P=0.0003). MVD also was significantly correlated with ascites cytology (P=0.0377). There was no correlation between microvessel count and lymph node status, depth of invasion, disease stage, lymph-vascular space invasion, grade, or parametrial involvement. Patients with high MVD (> or=75) had significantly worse PFS and OS than those with low MVD (< 75) (log rank test, P=0.0180 and 0.0199, respectively). Multivariate analysis showed that MVD correlated significantly and independently with PFS and OS.

CONCLUSIONS

In adenocarcinoma of the cervix, MVD is an independent prognostic factor for PFS and OS.

Pharmacokinetics of nimustine, methotrexate, and cytosine arabinoside during cerebrospinal fluid perfusion chemotherapy in patients with disseminated brain tumors

OBJECTIVE

This study was conducted to evaluate the pharmacokinetics of anticancer drugs in cerebrospinal fluid (CSF) perfusion chemotherapy.

METHODS

We administered CSF perfusion chemotherapy with nimustine (ACNU), methotrexate (MTX), and cytosine arabinoside (Ara-C) to three patients with disseminated malignant brain disease. The drugs were infused via Ommaya's reservoirs to the lateral ventricle and removed by drainage from the temporal lobe or lumbar spine. CSF and plasma concentrations of the anticancer drugs were determined by high-performance liquid chromatography and fluorescence polarization immunoassay.

RESULTS

The concentrations of anticancer drugs in the discharged CSF peaked about 40 min after the start of a 1-h CSF perfusion. After the perfusion, the drug level in CSF decreased exponentially in a monophasic manner. ACNU and Ara-C were not detectable in the discharged CSF in the temporal lobe at 6 h and 48 h after perfusion, respectively, but MTX was detectable at 48 h. The maximum concentration ratio of anticancer drugs and the duration of perfusion were inversely correlated. The plasma concentrations of anticancer drugs were much lower than those in CSF. The half-life of ACNU was very short (0.2-1.1 h), whereas the half-lives of MTX and Ara-C were relatively long (2.81-13.5 h and 1.84 6.25 h, respectively). The half-lives of the anticancer drugs in CSF tended to decrease with repeated CSF perfusion chemotherapy.

CONCLUSION

Results suggest that CSF perfusion chemotherapy enables a high concentration of anticancer drug to be administered for dissemination in the spinal cord within a short period of time, with minimal adverse effects.

Tumor-associated antigen 22-1-1 expression in the uterine cervical squamous neoplasias

We have reported that a novel tumor-associated antigen (Ag), 22-1-1, was expressed in cancer cells derived mainly from the uterus and ovary [K. Sonoda et al., Cancer (Phila.), 77: 1501-1509, 1996]. The 22-1-1 Ag existed not only in adenocarcinomas but also in squamous cell carcinomas in the uterine cervix. Here, a relationship between tumor progression and invasion and 22-1-1 Ag expression was investigated in squamous cell neoplasms of the uterine cervix using immunohistochemical staining. The 22-1-1 Ag was not detected in normal uterine cervix (0 of 10 total cases) and dysplasias (0 of 47 total cases). However, 20% of carcinoma in situ (4 of 20 total cases) and 16.7% of microinvasive carcinomas (2 of 12 total cases) stained positively for 22-1-1 Ag. Moreover, areas depicting microinvasion on histology in uterine cancers (stage Ia) were more strongly stained than carcinoma in situ lesions. 22-1-1 Ag expression was found to be more frequent in invasive squamous cell carcinomas (82.6%; 57 of 69 total cases). The 22-1-1 Ag existed both in the cytoplasm and on the membrane of cancer cells. These findings suggest that 22-1-1 Ag expression might be related to tumor cell progression and invasion in the uterine cervical squamous cell epithelium.

Basaloid-squamous cell carcinoma of the oral mucosa: report of two cases and study of the proliferative activity

Two cases of basaloid-squamous cell carcinoma (BSC) of the oral mucosa are described. The first case occurred at the floor of the mouth in a 58-year-old man, and the second case occurred at the mandibular gingiva in a 79-year-old woman. The laboratory data of the first case showed a positive response to hepatitis C virus antibody. In the first case, the tumor mass measured 4 x 4 cm in size, and was located at the lingual side of the median mandible beside the sublingual gland. In the second case, the tumor mass measured 25 x 15 mm in size, and was located in the alveolar mucosa of the right mandible. Histologically, both tumors showed a neoplastic epithelium arranged in a solid pattern with evidence of peripheral palisading, central necrosis, and some squamous differentiation. The proliferative activities of the BSC were compared with conventional squamous cell carcinomas (SCC) in the oral floor and gingiva, respectively, by employing a sensitive argyrophilic nuclear organizer region (AgNOR) staining method. The number of AgNOR per nucleus of the BSC was higher than that of any other SCC cases. The results support the opinion that BSC of the oral mucosa has a worse prognosis than conventional SCC.

A case of pulmonary embolism caused by paroxysmal nocturnal hemoglobinuria

A patient with pulmonary embolism caused by paroxysmal nocturnal hemoglobinuria (PNH) is described. PNH sometimes causes venous thrombosis in the extremities, hepatic vein, or cerebral vein, but pulmonary embolism rarely occurs.

Human placental extract stimulates liver regeneration in rats

The effect of human placental extract (HPE) on liver regeneration in rats was investigated. After intravenous administration of HPE to a-naphthylisothiocyanate (ANIT)-intoxicated rats, the labeling index in hepatocytes was significantly increased to a level 16.5 times higher than that of the control. A 1/500 dilution of HPE directly stimulated DNA synthesis of the hepatocytes in primary culture. HPE heated at 121 degrees C did not stimulate the labeling index in vivo or hepatocyte DNA synthesis in primary culture, suggesting that HPE contains heat-unstable but potent mitogens for hepatocytes. HPE contains hepatocyte growth factor (HGF), but the mitogenic effect of HPE cannot be explained by the effect exerted by HGF alone, since both the labeling index in vivo and hepatocellular DNA synthesis in vitro stimulated by HPE were much higher than those stimulated by HGF alone when the applied doses of HGF were set to be almost the same level between each case. When HPE was fractionated on a heparin-sepharose column, the mitogenic effect of HPE was found to be located mainly in the heparin-bound fraction. Hepatocyte DNA synthesis induced by this fraction was enhanced cooperatively by the heparin-unbound fraction, suggesting that there are some modulators in the heparin-unbound fraction which enhance the proliferative activity of the heparin-bound fraction by a synergetic mechanism. Both HPE and heated HPE completely recovered the biochemical marker activity for liver function (glutamic-pyruvic transaminase, GPT; alkaline phosphatase, ALP; lactate dehydrogenase, LAP; gamma-glutamyltransferase, gamma-GTP activities and the bilirubin concentration) almost to the control level in the serum of ANIT-intoxicated rats, indicating that HPE also contains a heat-stable fraction which repairs liver function.

Sclerosing stromal tumor of the ovary: a clinicopathologic, immunohistochemical, ultrastructural, and cytogenetic analysis with special reference to its vasculature

Sclerosing stromal tumor (SST) is a rare ovarian neoplasm occurring predominantly in young women and is histologically characterized by cellular heterogeneity, prominent vasculature, and a pseudolobular appearance composed of cellular and hypocellular areas. In the current study, three cases of SST were ultrastructurally examined and the tumors were found to be composed of several kinds of cells, i.e., luteinized thecalike cells, spindle-shaped fibroblastic cells, and primitive mesenchymal cells. These findings thus supported the ovarian stromal origin of SST. Twelve cases of SST also were analyzed immunohistochemically and demonstrated an expression of vascular permeability factor/vascular endothelial growth factor (VPF/VEGF) in the luteinized thecalike cells and its receptor, fms-like tyrosine kinase 1 (flt-1), in capillary to medium-sized blood vessels. Reverse transcription-polymerase chain reaction (RT-PCR) also showed an expression of VPF/VEGF messenger RNA in SSTs. Accordingly, the characteristic vasculature and edema of SSTs were considered to be associated with the expression of VPF/VEGF. In addition, a fluorescence in situ hybridization (FISH) analysis also showed cells with three copy number of chromosome 12 in 13-21% of all examined SST cells, which suggested the presence of chromosome 12 trisomy in SSTs as well as in other ovarian stromal tumors.

The significance of peritoneal cytology in uterine cervix and endometrial cancer

OBJECTIVE

The purpose of this study was to determine the incidence of positive peritoneal cytology and to elucidate the prognostic value of peritoneal cytology in patients with uterine cervix and endometrial cancer.

MATERIALS AND METHODS

The incidence of positive peritoneal cytology was investigated in 642 patients including 339 uterine cervix and 303 endometrial cancers. Survival was estimated by the Kaplan-Meier method in a subgroup of 116 stage II cervix and 199 stage I endometrial cancers, and multivariate analysis using Cox's proportional hazards model was used to identify an independent prognostic factor.

RESULTS

The incidence of positive peritoneal cytology was found to be 9% in uterine cervix cancer and 15% in endometrial cancer. The incidence was higher in patients with some clinicopathologic status such as advanced stage, lymph node metastasis, ovarian metastasis, and deeper myometrial invasion. The 5-year survival rate for patients with positive or negative peritoneal cytology was 44 or 80% in stage II cervix cancers and 80 or 92% in clinical stage I endometrial cancers, respectively. Multivariate analysis revealed that independent prognostic determinants were pelvic and paraaortic lymph node metastasis and peritoneal cytology in stage II cervix cancer and peritoneal cytology in stage I endometrial cancer. Proper treatment protocol should be scheduled for patients with positive peritoneal cytology.

Tortuosity of the Cervical Segment of the Internal Carotid Artery in AVM Patients

SUMMARY

The correlation between the degree of tortuosity of the cervical segment of the internal carotid artery (CICA) and the size of the nidus in AVM patients was investigated on angiograms. Fifteen AVM patients underwent embolization of vessels that were fed primarily by the internal carotid artery. The patients were divided into two groups according to the size of nidus: in group 1 (n=5), the size of the nidus was rated as small (less than 6 cm), in group 2 (n=10) as large (greater than 6 cm). The tortuosity was rated as mild, moderate, or severe. The tortuosity of the ipsilateral CICA in group 1 was severe while in group 2 it was either mild or moderate. The tortuosity of the CICA seems to be an important factor to be considered when distal embolization is contemplated in AVM patients.

Long-term treatment of indomethacin reduces vertebral bone mass and strength in ovariectomized rats

We investigated the effect of the long-term treatment of indomethacin, on lumbar spinal bone mineral density (LSBMD), cancellous bone mass, structure, and strength of vertebral body in old ovariectomized (OVX) rats. Ten-month-old female Wistar rats were divided into five groups: the sham operated + vehicle (sham + VEH) group, the OVX + vehicle (OVX + VEH) group, the OVX + indomethacin (IN) 1.5 mg/kg/week (OVX + IN1.5) group, the OVX + IN 6.0 mg/kg/week (OVX + IN6.0) group, and the OVX + IN 15.0 mg/kg/week (OVX + IN15.0) group. IN or vehicle were given by subcutaneous injection (s.c.) three times per week. The treatments were started at 1 week after operation and continued for 24 weeks. LSBMD (L2-L5) was measured at 0, 12, and 24 weeks after the beginning of treatment. At the end of the experimental period, the animals were sacrificed, and bone histomorphometrical and biomechanical analysis of lumbar vertebral body were done. LSBMD, trabecular bone volume (BV/TV), and trabecular thickness (Tb.Th) decreased significantly in a dose-related manner with IN. In the OVX + IN15.0 group, LSBMD decreased by 12.7%, BV/TV decreased by 65.5%, and Tb.Th decreased by 32.8%, compared with the OVX + VEH group. In addition, the maximum stress in a compressive mechanical test of L4 vertebral body in OVX groups was also decreased in a dose-related manner with IN, and this value in the OVX + IN15.0 group was 31.3% lower than in the OVX + VEH group. We conclude that long-term treatment with IN accentuated the OVX-related decrease in trabecular bone mass and the compressive strength of lumbar vertebrae.

Alteration of proto-oncogenes during apoptosis in the oral squamous cell carcinoma cell line, SAS, induced by staurosporine

Staurosporine (ST) has been reported to induce apoptosis in many kinds of cultured cells. The pathway of the apoptosis induced by ST is still not clear. Certain proto-oncogene expressions have been shown to be involved in the apoptotic pathway. The present study characterized apoptosis induced by ST in the oral squamous cell carcinoma cell line, SAS, focusing on the alteration of proto-oncogene expression. SAS showed typical apoptotic features upon exposure to ST. We compared the level of gene expression in apoptosis induced by ST with that by withdrawal of serum, which is a common system to induce apoptosis. By RT-PCR analysis, ST-induced apoptosis showed c-fos and c-jun up-regulation, whereas serum withdrawal-induced apoptosis showed c-jun up-regulation and the same levels of p21/waf-1 and c-myc. These results indicate that ST can rapidly induce apoptosis in SAS, possibly via a c-fos and c-jun pathway.

Basaloid-squamous cell carcinoma of the floor of the mouth: characterization of a cell line

Since it was first described in 1986, basaloid-squamous cell carcinoma (BSC) has been considered a distinct variant of squamous cell carcinoma that occurs in a variety of anatomic sites, including the head and neck region. We report the characterization of the first cell line established from a basaloid-squamous cell carcinoma of the floor of the mouth. The cell line exhibited a highly invasive capacity, indicating that BSC has very aggressive behavior. This cell line may be a useful model for elucidation of the biological characteristics of BSC.

Angiogenesis in endometrial carcinoma

BACKGROUND

Tumor angiogenesis is essential for tumor growth and metastases. Recently, microvessel density (MVD), a measure of tumor angiogenesis, has been found to have prognostic significance for predicting metastasis and survival in many tumor types. This study was conducted to determine how MVD was related to several clinicopathologic parameters and correlated with metastasis and survival in patients with endometrial carcinoma.

METHODS

From 1979 through 1989, 85 cases of clinical Stage I and II endometrial carcinomas treated initially by hysterectomy with pelvic lymph node dissection were reviewed histologically. All hysterectomy specimens were stained immunohistologically for factor VIII-related antigen. MVD was counted in a x200 field (x20 objective lens and x10 ocular lens, 0.785 mm2 per field) in the most active area of neovascularization. Results were expressed as the highest number of microvessels identified within any single x200 field. Statistical analysis included the Mann-Whitney U test, Kruskal-Wallis test of variance, and the Spearman rank correlation test. Survival was calculated using the Kaplan-Meier method and differences in survival were analyzed using the log rank test. MVD and several other prognostic parameters were examined for their correlation with progression free survival (PFS) and overall survival (OS) by a multivariate analysis according to the Cox proportional hazards model.

RESULTS

MVD was significantly correlated with tumor grade (P = 0.0281), myometrial invasion (P = 0.0282), and lymph-vascular space invasion (P = 0.0073). There was no correlation between microvessel count and lymph node status and stage. Patients with a high MVD (> or =60) had significantly worse PFS and OS than those with a low MVD (<60) (log rank test, P = 0.0116 and P = 0.0096, respectively). Multivariate analysis showed that MVD correlated significantly and independently with PFS and OS.

CONCLUSIONS

In this study, MVD was found to be an independent prognostic factor for PFS and OS in patients with endometrial carcinoma.

Changes in the expression of gap junction proteins (connexins) in hamster tongue epithelium during wound healing and carcinogenesis

We examined changes in the expression and localization of connexin proteins and transcripts by means of immunofluorescence and in situ hybridization in normal conditions, wound healing and carcinogenesis using hamster tongue epithelium, in which differentiation, migration and growth of keratinocytes takes place physiologically and pathologically. In normal hamster tongue epithelium, immunofluorescent staining showed that Cx26 and Cx43 proteins were localized differently during differentiation of keratinocytes, but in in situ hybridization, the localization of Cx26 and Cx43 transcripts overlapped considerably, suggesting that the different localization of Cx26 and Cx43 proteins in squamous epithelium is largely regulated at post-transcriptional levels. During wound healing, the expression and localization of connexin proteins and transcripts were changed drastically. Shortly (6 h) after injury the expression of Cx26 and Cx43 proteins decreased at wound edges, but by 1-3 days after injury the expression of both proteins increased and both proteins co-localized to the same spots in the epithelium near wound edges. During carcinogenesis, the increased expression of Cx26 and Cx43 proteins and their transcripts and co-localization of both proteins occurred in papillomas, and the expression of Cx26 was reduced as cancer cells became morphologically less differentiated. We also found, that during wound healing in papillomas, squamous cell carcinomas and keratinocytes, Cx26 and Cx43 proteins were localized aberrantly in the cytoplasm, especially around nuclei, rather than on plasma membranes. These results indicate that quantitative and qualitative changes in connexin expression are associated with differentiation, migration and proliferation of keratinocytes in squamous epithelium.

Early adenocarcinoma of the uterine cervix

The purpose of this study was to evaluate the prognostic significance of the tumor depth, horizontal spread, and volume in early cervical adenocarcinoma while excluding adenocarcinoma in situ. Thirty cases who had been treated at our institution having cervical adenocarcinoma with a tumor depth of less than 5 mm were clinicopathologically reviewed. The volumes were estimated based on the portion with the largest tumor surface area by multiplying three dimensions: depth, horizontal spread, and a third dimension. The third dimension was calculated by the method of Burghardt to be 1.5 times the largest measured depth or spread. Two of the 30 patients recurred in the vagina at 18 and 163 months after the initial operation; the former patient died of disease 87 months postoperatively. The remaining 28 patients are all doing well without recurrence (range of follow-up from 24 to 232 months; median 79 months). No pelvic or paraaortic lymph node metastases were seen in 25 and 22 cases, respectively. None of the 21 cases with a lesion measuring less than 3 mm in depth had recurrence. On the other hand, 1 of 23 with a tumor volume up to 500 mm3 had recurrence. The estimated 5-year progression-free survival rates for patients with cervical adenocarcinoma with a depth of less than 3 mm and those with a depth of more than 3 mm were 100 and 88.89%, respectively (P = 0.116). The depth of stromal invasion may therefore be a good predictor of lymph node metastasis and recurrence in early cervical adenocarcinoma.

Relationship between pelvic lymph node involvement and other disease sites in patients with ovarian cancer

In 109 patients with epithelial ovarian cancer, 25 (23%) had pelvic lymph node (PLN) metastasis. Positive rates of PLN metastasis according to the clinical stage based on disease distribution except retroperitoneal lymph node were 2% for stage I, 6% for stage II, 44% for stage III, and 64% for stage IV. The nine disease sites, such as subdiaphragmatic surface, liver and spleen capsule, intestine and mesentery, omentum, pelvic peritoneum, sigmoid colon and rectum, uterus and tubes, peritoneal cytology, and paraaortic lymph node (PAN), were found to have a statistically significant relationship with PLN metastasis by univariate analysis. Multivariate analysis using a logistic regression model selected the omentum and PAN as independent factors with a statistical significance. The incidence of PLN metastasis in epithelial ovarian cancer with the above two parameters can be assumed to be greater than that without the two parameters by 42.6 times. The present data suggested that for the disease with PAN and/or omental metastasis, removal of the PLN may be mandatory from the standpoint of cytoreduction.

[Benefit of monitoring the level of blood flecainide acetate in an elderly patient with ventricular premature contractions]

A 67-year-old woman without organic heart, disease had symptomatic ventricular premature contractions. Because class Ia, Ib and IV antiarrhythmic drugs did not prevent the premature contractions, the patient was treated with flecainide acetate at a dose of 50 mg t.i.d. Adverse reactions were noted. After measurement of the blood drug level, the dose was reduced to 50 mg b.i.d. The adverse reactions disappeared, and the arrhythmia was controlled. Flecainide acetate has a relatively long blood elimination half-life and a narrow safety margin. When some antiarrhythmic drugs are used in elderly patients, blood drug level monitoring is useful in preventing adverse reactions and in designing appropriate therapy.

Adenocarcinoma of the uterine cervix with predominantly villogladular papillary growth pattern

We reviewed the clinical and pathological features of seven cases of adenocarcinoma of the uterine cervix with predominantly villogladular papillary growth pattern. The patients, who ranged in age from 33 to 54 (mean, 45) years, underwent radical hysterectomy. In all seven cases, the tumors were papillary exophytic architecture lined by stratified epithelial cells with mild to moderate nuclear atypicality. In one of seven cases, the majority of the tumor showed villogladular papillary component, but the small foci of small cell carcinoma was present in the endocervical end of the tumor. The lymph vascular invasion was demonstrated in two of seven cases, and these two had pelvic lymph node metastases. One of these two patients had recurrence 30 months after the initial treatment and died of disease after 46 months. The follow-up ranged from 9 to 169 (median, 46) months. The presence or absence of lymph vascular invasion and minor components of this tumor such as small cell carcinoma, serous cell carcinoma, and clear cell carcinoma with a poor prognosis may be important histological findings before deciding to manage this tumor by the conservative treatment.

Reconstruction of the posterior inferior cerebellar artery in the treatment of giant aneurysms. Report of two cases

Two techniques of revascularizing the posterior inferior cerebellar artery (PICA) during aneurysm surgery are presented. One involves transposition of the PICA to the vertebral artery proximal to the aneurysm using a superior temporal artery (STA) as a graft. This is used in cases in which the PICA has branched off from the wall of the giant vertebral artery aneurysm. The other technique involves end-to-end anastomosis of the PICA after excision of a giant distal PICA aneurysm located at the cranial loop near the roof of the fourth ventricle. The reconstructions of the PICA described here are surgical procedures designed to preserve normal blood flow in the PICA in patients treated for giant aneurysms involving that artery.