Postcomparison of [(18) F]-fluorodeoxyglucose uptake in the brain after short-term bright light exposure and no intervention.

OBJECTIVE: Bright light therapy is widely used as the treatment of choice for seasonal affective disorder. Nonetheless, our understanding of the mechanisms of bright light is limited and it is important to investigate the mechanisms. The purpose of this study is to examine the hypothesis that bright light exposure may increase [(18) F]-fluorodeoxyglucose (FDG) uptake in olfactory bulb and/or hippocampus which may be associated neurogenesis in the human brain. METHOD: A randomized controlled trial comparing 5-day bright light exposure + environmental light (bright light exposure group) with environmental light alone (no intervention group) was performed for 55 participants in a university hospital. The uptake of [(18) F]FDG in olfactory bulb and hippocampus using FDG positron emission tomography was compared between two groups. RESULTS: There was a significant increase of uptake in both right and left olfactory bulb for bright light exposure group vs. no intervention group. After adjustment of log-transformed illuminance, there remained a significant increase of uptake in the right olfactory bulb. CONCLUSION: The present findings suggest a possibility that 5-day bright light exposure may increase [(18) F]FDG in the right olfactory bulb of the human brain, suggesting a possibility of neurogenesis. Further studies are warranted to directly confirm this possibility.

Life-threatening hemorrhage and prolonged wound healing are remarkable phenotypes manifested by complete plasminogen activator inhibitor-1 deficiency in humans.

BACKGROUND: Plasminogen activator inhibitor-1 (PAI-1) is the primary physiological regulator of urokinase plasminogen activator (uPA) and tissue plasminogen activator (tPA) activity. A number of studies have shown that elevated levels of PAI-1 are related to pathological states such as an increased risk of arterial thrombotic events and a poor prognosis for cancer patients; however, there are few reports about PAI-1 deficiency in humans because the disorder is very rare. OBJECTIVE: To understand the in vivo impact of a complete PAI-1 deficiency, Serpine1(-/-) mice were generated; a number of in vivo studies have been conducted to elucidate the function of PAI-1 using Serpine1(-/-) mice. The phenotypes demonstrated in Serpine1(-/-) mice, however, were quite different from those in humans. Therefore, it is necessary to find out and analyze SERPINE1 deficiency in humans. PATIENT AND METHODS: The patient is a 47-year-old woman who has had multiple episodes of major bleeding. Although most of the patient's blood coagulation factors were functionally normal, her PAI-1 antigen levels were undetectable. Therefore, DNA sequencing of the SERPINE1 gene were analyzed. RESULTS: The proband had a homozygous 1-bp duplication (C) at exon 3 (c.356dupC; p.Ile120AspfsX42). Both wild-type PAI-1 (42.7 kDa) and mutated (Mut) PAI-1 (14.7kDa) were expressed in COS-1 cells, although the level of Mut PAI-1 expressed in the cell lysates was much lower. Wild-type PAI-1 was observed in the culture supernatant, whereas no Mut PAI-1 was detected in the supernatant. CONCLUSIONS: Considering the results of the present study, the translation of mouse studies to humans must be performed with great care.

Intramedullary spinal cord metastases of malignant melanoma: an autopsy case report and review of the literature.

INTRODUCTION: Compared with brain metastasis of malignant melanoma (MM), spinal metastasis, and in particular intramedullary spinal cord metastasis (ISCM), is extremely rare. CASE: A 78-year-old female patient suffered from disturbance of gait and mild dementia. Radiological investigations revealed multiple hemorrhagic lesions in the brain. She underwent surgical resection of a right parietal lesion, the diagnosis of which was MM. Re-examination of her past history revealed that the patient had undergone surgical resection of a nevus on her left cheek 3 years previously, the diagnosis of which had been MM. After she had died of the tumor 3 months later, complete autopsy was performed. Multiple ISCMs with hemorrhage were detected in the cervical, thoracic, and lumbar cord. DISCUSSION: We found 9 cases of ISCM of MM in the literature, 5 of which were located in the cervical cord, 3 in the thoracic cord, and 1 in the lumbar cord. One difference between the findings noted in the literature and those in the present case involved the cross-sectional location of metastases in the spinal cord. In the present case, it appeared that postoperative management for the left buccal melanoma, which did not include adjuvant therapy, affected the postoperative clinical course. The prognosis was also affected by overlooking of ISCM. The brain metastases in the present case induced deterioration of her neurological symptoms rapid enough that the possibility of ISCM was not considered. On evaluation of tumor spread from MM, it is important to take into account not only intracranial metastases but ISCM as well.

Microelectrode findings and topographic reorganisation of kinaesthetic cells after gamma knife thalamotomy.

A 64-year-old woman with Parkinson is disease had a severe resting tremor that was not completely relieved by right-sided gamma knife thalamotomy (GKT). We performed bilateral staged thalamic deep brain stimulation (DBS) and compared the right and left ventral intermediate nucleus (Vim) of the thalamus including the frequency of single units recorded with microelectrodes, and also the somatotopical distribution of kinaesthetic cells (Ki). The average frequency of units for the presumed left Vim exceeded that of the right (22.6 +/- 19.2 Hz vs. 14.3 +/- 8.8 Hz). Regarding the somatotopic distribution of Ki, the receptive field for the leg, which is usually situated in the dorsolateral Vim, was more widely scattered in the right Vim than the non-lesioned left side. Our findings raise the possibility that the specific properties of the neurons changed due to partial coagulation by GKT within both the coagulated and the surrounding thalamic lesions.

Serum CA125 level before the development of ovarian cancer.

BACKGROUND: Little is known about the natural history of ovarian cancer with respect to the change of serum CA125 level. METHODS: The Shizuoka Cohort Study on Ovarian Cancer Screening (SCSOCS) Trial contains approximately 100,000 data on serum tumor marker CA125 prospectively obtained from more than 70,000 women. We reviewed the clinical charts and collected serum samples 2 months to 9.4 years prior to the surgery were available. RESULTS: In 396 (95%) of the 419 patients with ovarian cancer, one serum sample was present before the diagnosis (mean, 4.1 years). The change of CA125 level before the diagnosis of ovarian cancer could be clearly separated into two groups according to the length of the following intervals: 47% (107/228) of patients with non-serous-type ovarian cancers develop secondarily from slightly elevated CA125 level (35

Risk of developing ovarian cancer among women with ovarian endometrioma: a cohort study in Shizuoka, Japan.

Although some studies have indicated that endometriosis may increase the risk of developing ovarian cancer, there are no data from epidemiologic studies in Japan. We prospectively analyzed all cases of ovarian endometrioma enrolled in the prefecture-wide Shizuoka Cohort Study on Endometriosis and Ovarian Cancer Programme, which was initiated in 1985. To evaluate the risk of ovarian cancer by time periods subsequent to ovarian endometrioma diagnosis, a cohort of 6,398 women with a clinically documented ovarian endometrioma in Shizuoka between 1985 and 1995 was identified from the Shizuoka Cancer Registry (SCR), with follow-up through 2002. Ovarian cancer incidence among cohort members was ascertained by linkage to the SCR using a unique person-identification number. Standardized incidence ratios (SIR) and their 95% confidence intervals (CI) were computed by a use of prefecture-wide rates of ovarian cancer, adjusted for age and calendar year. During follow-up of up to 17 years of the ovarian endometrioma cohort, 46 incident ovarian cancers were identified, yielding that the ovarian cancer risk was elevated significantly among patients with ovarian endometrioma (SIR = 8.95, 95% CI = 4.12-15.3). The SIR did not increase with increasing follow-up duration. The risk increased with increasing age at ovarian endometrioma diagnosis, with a SIR equal to 13.2 (95% CI = 6.90-20.9) in women above 50 years of age. Our findings for the first time support the hypothesis that ovarian endometrioma increases the subsequent risk of developing ovarian cancer in Shizuoka, Japan.

A phase I study of S-1 combined with weekly cisplatin for metastatic gastric cancer in an outpatient setting.

A dose-escalation study was conducted for patients with metastatic gastric cancer to determine the recommended dose of weekly intravenous (i.v.) cisplatin combined with a fixed dose of a new oral dihydropyrimidine dehydrogenase-inhibitory fluoropyrimidine, S-1, on an outpatient basis. Secondary endpoints were to define the toxicity profile and to determine tumour responses. S-1 was fixed at a dose of 70 mg/m(2)/day and was administered for 2 weeks followed by a 1-week rest. Three dose levels of cisplatin (10, 15 and 20 mg/m(2)) were studied. Cisplatin was infused over 30 min on days 1 and 8. 20 patients were enrolled. No dose-limiting toxicities (DLTs) were recorded during the administration of cisplatin up to 20 mg/m(2), except for grade 3 diarrhoea and stomatitis in one patient at dose level 3. No grade 4 adverse events occurred. However, grade 2 gastrointestinal adverse reactions, such as nausea and anorexia, were seen in 7 of 13 patients at dose level 3 within the first two treatment cycles. This was determined to be the maximum acceptable level that would not negate the advantages observed with use of an oral drug such as S-1. An objective tumour response was seen at all dose levels, and the overall response rate in the 18 patients evaluated was 61%. A higher response rate of 78% was observed in 9 patients who had received no prior chemotherapy. Oral S-1 with weekly cisplatin is a feasible and promising combination regimen that is appropriate for an outpatient setting. A randomised phase II study comparing this combination with S-1 alone in chemo-nai;ve patients is warranted.

Routine endoscopy using a magnifying endoscope for gastric cancer diagnosis.

BACKGROUND AND STUDY AIMS: It has been reported that the fine mucosal patterns of the gastric pits can be observed with magnification and this may assist in preliminary evaluation prior to histological diagnosis. The aim of this prospective study was to clarify the relationship between the fine mucosal patterns of gastric lesions and histological findings, and also to evaluate the usefulness of magnifying endoscopy during routine endoscopy. PATIENTS AND METHODS: A recently developed magnifying video endoscope, which enables magnification up to 80 times, was used for gastrointestinal endoscopy in 318 patients between January 2000 and January 2001, at the National Shikoku Cancer Center. In total, 232 lesions were detected. However, patients diagnosed by conventional endoscopy as having advanced gastric cancer, malignant lymphoma, or submucosal tumor were excluded from the study. The endoscopic findings for 211 lesions included in this study were compared with the histological findings. RESULTS: Coarse and irregular mucosal patterns were observed in elevated-type cancers by magnifying endoscopy, and in depressed-type cancers there was a finer pit pattern than in the surrounding mucosa, destruction or disappearance of the mucosal microstructure, and abnormal capillary vessels. The magnifying endoscopy results were closely related to the mucosal microstructure observed by dissecting microscopy and to the histological features. The rate of presumptive diagnosis of small gastric cancers was significantly higher when a magnifying endoscope was used compared with conventional endoscopy. In this study, the sensitivity and specificity of magnifying endoscopy as a diagnostic method were 96.0% and 95.5%, respectively. CONCLUSIONS: The fine mucosal patterns and the features of capillary vessels, which were identified with the magnifying endoscope, correlated well with the pathological diagnosis. Magnifying endoscopy will be very useful in predicting the histological diagnosis during routine endoscopic procedures.

Cholesterol granuloma in the petrous apex: case report and review.

Cholesterol granuloma in the petrous apex presents with various symptoms of cranial nerve dysfunction, so the selection for surgical treatment remains controversial. We report a 41-year-old woman with a cholesterol granuloma at the left petrous apex, which was totally resected via a combined middle fossa and posterior transpetrosal approach. In a review of 92 cases, including our case, treated for petrous apex cholesterol granuloma between 1990 and 2001, 38 were men (41.3%) and 54 were women (58.7%). The mean age of these patients was 37.4 years (males were 35.2 years, females were 39.4 years). The most common presenting clinical symptom was hearing loss due to dysfunction of cranial nerve VIII. Seventy-nine patients, including our case, underwent operation, and 13 patients were managed without surgery. The most frequently selected surgical approach was middle cranial fossa approach. Revision surgery (including the 2 cases who underwent revision twice and three times) was performed in 12 patients (15.2%). In 92 cases, all of those who underwent total removal have not shown re-accumulation of cyst contents. On the other hand, 11.4% of the patients with or without permanent drainage route proceeded by subtotal removal of the cyst wall needed revision surgery because of stenosis of the drainage route. Therefore we conclude that the most important treatment for the prevention of re-accumulation of cyst contents may be the extent of the cyst wall resection rather than the establishment of permanent drainage route.

[A case of spontaneous rupture of a suprasellar cystic mass].

The author reported a case of a spontaneous rupture of a suprasellar cystic tumor. A 67-year-old man complained of bitemporal homonymous hemianopsia. His visual acuity was 0.02 on the right side and 0.04 on the left side. Skull XP revealed no abnormal findings, but brain CT scan showed a cystic mass without calcification in the suprasellar region. Brain MRI at the same lesion site depicted a low-intensity mass on T1-weighted image without gadolinium enhancement, and a high-intensity mass on T2-weighted image. The patient was treated conservatively because of complications such as diabetes mellitus, cerebral infarction and old myocardiac infarction. MRI taken 5 years after the initial MRI revealed disappearance of the suprasellar cystic mass. However, the patient's neurological findings, including visual signs, revealed no deterioration. His physical and radiological findings had remained uneventful. In this report, we reviewed the literatures about spontaneous rupture of suprasellar cystic tumors. It was considered that in this case, according to the neurological, radiological and CSF findings, the suprasellar cystic mass might be a Rathke's cleft cyst or arachnoid cyst.

Structure and function analysis of urinary trypsin inhibitor (UTI): identification of binding domains and signaling property of UTI by analysis of truncated proteins.

The binding of urinary trypsin inhibitor (UTI) to its binding sites/receptors on tumor cells inhibits cell invasion in a number of experimental systems and that UTI downregulates constitutive and phorbol ester-induced urokinase production by certain tumor cells. To determine whether the carbohydrate moieties and core protein are required for urokinase suppression, we obtained UTI derivatives that contained O-glycoside-linked N-terminal glycopeptide (UTIm1), N-glycoside-linked C-terminal tandem Kunitz domains (UTIm2), UTI lacking O-glycoside (UTIc), asialo UTI (UTIa), UTI lacking N-glycoside (UTIn), purified Kunitz domain II of UTI (HI-8), and recombinant Kunitz domain II of UTI (R-020). The IC(50) of inhibiting binding of (125)I-labeled UTI to cells was indistinguishable for UTIa, UTIn and intact UTI, whereas the IC(50) for inhibiting binding of (125)I-labeled UTI to cells was 2.5-, 25- and 29-fold greater for UTIm1, UTIm2 and UTIc than for native UTI. We next looked at the suppression of the urokinase expression by UTI derivatives. An enzyme-linked immunosorbent assay was carried out to measure secreted and cell-associated urokinase. Intact UTI, UTIa, or UTIn effectively suppressed urokinase expression, but UTIm1, UTIm2, UTIc, HI-8 and R-020 had no significant effect. These data show that UTI requires either the N-terminal extension with the O-linked carbohydrate moiety (chondroitin 4-sulfate sugar side chain; Ala1 to Lys21 residues) or the Kunitz domain I (Lys22 to Arg77 residues) of UTI to bind to cells, but the urokinase expression was inhibited only by the O-glycoside-linked core protein without the N-glycoside side chain.

Studies on the mechanism of edematous changes at the endometrial stroma for implantation.

The endometrium undergoes edematous changes during the implantation period. Many factors may be involved in these biochemical reactions. We investigated the localization of inducible NO synthase (iNOS), interleukin-8 (IL-8), mast cell tryptase, neutrophil elastase, type III collagen, and CD44 in human endometrium. Immunohistochemical staining was performed by the labeled streptavidin-biotin method. iNOS was stained in the entire endometrial tissue from the midproliferative phase. The IL-8-positive cells, mast cells, and neutrophil elastase in the stroma increased toward the early to midsecretory phase. Type III collagen was arranged regularly in the stromal extracellular matrix during the proliferative phase; however, it was dissected during the secretory phase. CD44 was detected around stromal cells in the midsecretory phase. From these results, we propose the following mechanism. Initially, iNOS, expressed by the entire endometrial tissues from the midproliferative phase, catalyzes the production of NO. NO stimulates cells, supposed to be mast cells, to produce IL-8, which lets neutrophils migrate into the stroma. Neutrophils secrete elastase, which degrades type III collagen, generating spaces in the stroma. Hyaluronic acid adheres to CD44 around the stromal cells and retains water intermolecularly, finally forming the edematous matrix.

Characterization of binding properties of urinary trypsin inhibitor to cell-associated binding sites on human chondrosarcoma cell line HCS-2/8.

Urinary trypsin inhibitor (UTI) forms membrane complexes with UTI-binding proteins (UTI-BPs) and initiates modulation of urokinase-type plasminogen activator (uPA) expression, which results in UTI-mediated suppression of cell invasiveness. It has been established that suppression of uPA expression and invasiveness by UTI is mediated through inhibition of protein kinase C-dependent signaling pathways and that human chondrosarcoma cell line HCS-2/8 expresses two types of UTI-BPs; a 40-kDa UTI-BP (UTI-BP(40)), which is identical to link protein (LP), and a 45-kDa UTI-BP (UTI-BP(45)). Here we characterize binding properties of UTI-BPs.UTI complexes in the cells. In vitro ligand blot, cell binding and competition assays, and Scatchard analyses demonstrate that both UTI-BP(40) and UTI-BP(45) bind (125)I-UTI. A deglycosylated form of UTI (NG-UTI), from which the chondroitin-sulfate side chain has been removed, binds only to UTI-BP(40). Additional experiments, using various reagents to block binding of (125)I-UTI and NG-UTI to the UTI-BP(40) and UTI-BP(45) confirm that the chondroitin sulfate side chain of UTI is required for its binding to UTI-BP(45). Analysis of binding of (125)I-UTI and NG-UTI to the cells suggests that low affinity binding sites are the UTI-BP(40) (which can bind NG-UTI), and the high affinity sites are the UTI-BP(45). In addition, UTI-induced suppression of phorbol ester stimulated up-regulation of uPA is inhibited by reagents that were shown to prevent binding of UTI to the 40- and 45-kDa proteins. We conclude that UTI must bind to both of the UTI-BPs to suppress uPA up-regulation.

Immunologic studies in presumed amniotic fluid embolism.

OBJECTIVE: To evaluate the potential role of immunologic mechanisms that involve mast cell degranulation (anaphylaxis) or complement activation in the mechanism of amniotic fluid embolism. METHODS: This study was a case series of nine women with presumed amniotic fluid embolism and a control group of 22 women who had normal labor. Women were from community and tertiary referral hospitals in Japan and the United States. Main outcome measures were maternal peripartum complement levels (C3 and C4), serum levels of tryptase, urinary histamine concentrations, and serum levels of a fetal antigen (sialyl Tn). RESULTS: Serum tryptase and urinary histamine measurements were negative in women with amniotic fluid embolism; seven of nine had elevated levels of fetal antigen. All eight who had serum available for testing had abnormally low levels of complement. Mean C3 level of 44.0 mg/dL and C4 level of 10.7 mg/dL were significantly lower than corresponding postpartum control values of 117.3 mg/dL and 29.4 mg/dL (P =.018 for C3, P =.012 for C4). Postpartum C3 and C4 levels decreased by 8% and 5%, respectively, compared with intrapartum values (P =.003 for C3, P =.021 for C4) but were still within normal range. CONCLUSION: Serologic findings suggest a role for complement activation in the mechanism of amniotic fluid embolism. Laboratory data from this series did not implicate mast cell degranulation (anaphylaxis) in the pathophysiology of the disease.

Suppression of urokinase expression and invasiveness by urinary trypsin inhibitor is mediated through inhibition of protein kinase C- and MEK/ERK/c-Jun-dependent signaling pathways.

Urinary trypsin inhibitor (UTI), a Kunitz-type protease inhibitor, interacts with cells as a negative modulator of the invasive cells. Human ovarian cancer cell line, HRA, was treated with phorbol ester (PMA) to evaluate the effect on expression of urokinase-type plasminogen activator (uPA), since the action of uPA has been implicated in matrix degradation and cell motility. Preincubation of the cells with UTI reduced the ability of PMA to trigger the uPA expression at the gene level and at the protein level. UTI-induced down-regulation of PMA-stimulated uPA expression is irreversible and is independent of a cytotoxic effect. Down-regulation of uPA by UTI is mediated by its binding to the cells. We next asked whether the mechanism of inhibition of uPA expression by UTI was due to interference with the protein kinase C second messenger system. An assay for PKC activity demonstrated that UTI does not directly inhibit the catalytic activity of PKC and that PMA translocation of PKC from cytosol to membrane was inhibited by UTI, indicating that UTI inhibits the activation cascade of PKC. PMA could also activate a signaling pathway involving MEK1/ERK2/c-Jun-dependent uPA expression. When cells were preincubated with UTI, we could detect suppression of phosphorylation of these proteins. Like several types of PKC inhibitor, UTI inhibited PMA-stimulated invasiveness. We conclude that UTI markedly suppresses the cell motility possibly through negative regulation of PKC- and MEK/ERK/c-Jun-dependent mechanisms, and that these changes in behavior are correlated with a coordinated down-regulation of uPA which is likely to contribute to the cell invasion processes.

Suppression of urokinase-type plasminogen activator expression from human ovarian cancer cells by urinary trypsin inhibitor.

Urinary trypsin inhibitor (UTI), a Kunitz-type protease inhibitor, efficiently inhibits tumor cell invasion and metastasis. We examined the effect of UTI on urokinase-type plasminogen activator (uPA) expression in ovarian cancer cell lines, HOC-I and HRA. By Northern blot, Western blot, ELISA, and zymographic analyses, we demonstrated that UTI inhibited the expression of uPA mRNA and protein in these cells in a time- and dose-dependent manner, independent of whether induction was triggered by phorbol ester. Monoclonal antibody 4G12, which inhibits UTI binding to the cells, produced a dose-dependent abrogation in UTI-mediated down-regulation of uPA expression. These data suggest that UTI significantly down-regulates tumor cell uPA mRNA expression and protein secretion, and that UTI binding to the cells is necessary to exert the UTI's action.

One- and two-dimensional 13C-1H/15N- 1H dipolar correlation experiments under fast magic-angle spinning for determining the peptide dihedral angle phi.

A recently proposed 13C-1H recoupling sequence operative under fast magic-angle spinning (MAS) [K. Takegoshi, T. Terao, Solid State Nucl. Magn. Reson. 13 (1999) 203-212.] is applied to observe 13C-1H and 15N-1H dipolar powder patterns in the IH-15N- 3C- H system of a peptide bond. Both patterns are correlated by 15N-to-13C cross polarization to observe one- or two-dimensional (1D or 2D) correlation spectra, which can be simulated by using a simple analytical expression to determine the H-N-C-H dihedral angle. The 1D and 2D experiments were applied to N-acetyl[1,2-13C,15N] DL-valine, and the peptide q angle was determined with high precision by the 2D experiment to be +/- 155.0 degrees +/- 1.2 degrees. The positive one is in good agreement with the X-ray value of 154 degrees +/- 5 degrees. The 1D experiment provided the value of phi = +/- 156.0 degrees +/- 0.8 degrees.

Human myometrial cells in culture express specific binding sites for urinary trypsin inhibitor.

Urinary trypsin inhibitor (UTI), which is present in amniotic fluid, prevents uterine contractility during pregnancy possibly via specific binding protein mechanisms. To test for the presence of UTI binding sites on the cell surface, we prepared cultured myometrial cells obtained at biopsy from 12 pregnant women and performed binding, competition, and cross-linking experiments using a specific radiolabelled UTI as a ligand. We report for the first time two classes of binding sites of differing affinities. Scatchard analysis at 4 degrees C, using radioiodinated UTI, revealed that UTI binds to 35 000 high affinity binding sites/cell (K(d) = 9.1x10(-9) mol/l) and 450 000 lower affinity binding sites/cell (K(d) = 3.5x10(-7) mol/l) in cultured myometrial cells. It appears to be the low affinity site that is internalized, and this has been identified as a protein of approximately 45 kDa by cross-linking and immunoaffinity labelling studies. Monoclonal antibodies against the NH(2)-terminal fragment of UTI abrogated specific binding of this protein to the cells. Treatment of the cells with hyaluronidase resulted in >80% inhibition of the [(125)I]-labelled UTI binding to the cells. These data show that the UTI binding site, which is hyaluronidase sensitive, is expressed on the surface of human uterine myometrial cells to accumulate the UTI molecule during pregnancy.

Clinical significance of combined use of macrophage colony-stimulating factor and squamous cell carcinoma antigen as a selective diagnostic marker for squamous cell carcinoma arising in mature cystic teratoma of the ovary.

OBJECTIVES: Mature cystic teratoma of the ovary transforms into malignant tumors, mostly squamous cell carcinomas, at an incidence of approximately 2%. Preoperative diagnosis of squamous cell carcinoma arising in mature cystic teratoma of the ovary is a difficult task. The present study aims to assess whether combined use of two serum tumor markers, macrophage colony-stimulating factor (M-CSF) and squamous cell carcinoma antigen (SCC), is effective in preoperatively diagnosing squamous cell carcinoma arising in mature cystic teratoma of the ovary, distinguishing it from mature cystic teratoma without malignant transformation. METHODS: Serum levels of M-CSF and SCC were assayed using blood samples collected preoperatively from 31 patients with squamous cell carcinoma arising in mature cystic teratoma of the ovary and 133 patients with mature cystic teratoma of the ovary without malignant transformation. RESULTS: In 22 of the 31 (71.0%) patients with squamous cell carcinoma arising in mature cystic teratoma of the ovary, the serum M-CSF levels exceeded the upper limit of the normal level (1056 U/ml). This positive incidence of the elevated serum M-CSF levels was significantly higher compared with that (13.5%, 18/133) observed in patients with benign cystic teratoma of the ovary (P < 0.0001). Regarding the serum levels of SCC, 13 of 31 (41.9%) patients with malignant tumors showed positive values exceeding the cutoff value of 2.0 ng/ml. Again, this incidence of positive cases was significantly higher compared with that (15.0%, 20/133) observed in patients with benign tumors (P < 0.01). There was no correlation between the serum levels of M-CSF and SCC among patients with squamous cell carcinoma arising in mature cystic teratoma of the ovary. Patients with malignant tumors testing positive for elevated M-CSF did not necessarily test positive for SCC. Patients with positive values for excess M-CSF and/or SCC constituted 87.1% of the total (27/31). Even when patients were restricted to those with stage I tumors, a value as high as 83.3% (15/18) was still obtained for those testing positive for elevated M-CSF and/or SCC. CONCLUSION: Serum M-CSF was proven to be useful as a tumor marker for detecting squamous cell carcinoma arising in mature cystic teratoma of the ovary. Combined use of serum M-CSF and SCC as a marker seemed to be useful in the selective diagnosis of mature cystic teratoma of the ovary harboring malignant squamous carcinoma, discriminating it from that without malignant carcinoma.