Melatonin inhibits apoptosis and oxidative tissue damage in cisplatin-induced pulmonary toxicity in rats.

Introduction: Cisplatin is one of the most frequently used chemotherapeutics, which is known to cause both tumor and normal lung tissue damage through the generation of free radicals and cells apoptosis/necrosis. Melatonin is a neurohormone that regulates numerous physiological processes in the body both through receptor pathways and by maintaining tissue redox homeostasis. Material and methods: The extent of rat lung damage induced by cisplatin and the effects of melatonin on this process was determined based on the pathohistological changes and biochemical disturbances in tissue lipid peroxidation, protein carbonyl modification and in the activity of xanthine oxidase (XO), caspase-3 and DNases. Results: Histopathological analysis of rat lung tissue obtained from animals that received cisplatin found them to be edematous, with significant deterioration of alveolar epithelium. These morphological changes are accompanied by a significant increase in all studied oxidative stress-related parameters, as well as with the activity of apoptosis-related enzymes. A five-day treatment with melatonin completely prevented a cisplatin-induced increase in oxidative stress-related parameters and in the activity of XO, caspase-3 and alkaline DNase. Also, the histopathological changes observed during microscopic analysis were much less pronounced than in the group that received cisplatin only. Conclusions: These results can potentially be connected with the ability of melatonin to inhibit the activity of XO, caspase-3 and alkaline DNase and/or its ability to scavenge free radicals, thus preventing lung damage induced by cisplatin.

Pharmacological methods for ovarian function and fertility preservation in women with cancer: A literature review.

Oncofertility is an extremely significant topic that is increasingly being discussed owing to increased evidence indicating that fertility preservation does not affect the treatment outcomes of patients with cancer but significantly contributes to preserving life quality. The effect of chemotherapy can range from minimal effects to complete ovarian atrophy. Limited data are available on the effects of monoclonal antibodies and targeted therapies on the ovaries and fertility. Temporary ovarian suppression by administering a gonadotropin-releasing hormone agonist (GnRHa) during chemotherapy decreases the gonadotoxic effect of chemotherapy, thereby diminishing the chance of developing premature ovarian insufficiency (POI). At present, the concomitant administration of GnRH analogs during chemotherapy is the only accepted pharmacological method for preserving ovarian function. Notably, most randomized studies on the effectiveness of luteinizing hormone-releasing hormone agonists during chemotherapy in preventing POI have been conducted in women with breast cancer, with a considerably small number of studies on patients with hematological malignancies. Furthermore, most randomized controlled trials on breast cancer have revealed a decrease in treatment-induced POI risk, regardless of the hormone receptor status. In addition, studies on hematological malignancies have yielded negative results; nevertheless, the findings must be interpreted with caution owing to numerous limitations. Current guidelines from the American Society of Clinical Oncology and ESMO Clinical Practice Guidelines recommend sperm, oocyte, and embryo cryopreservation as a standard practice and only offering GnRHa to patients when proven fertility preservation methods are not feasible. In this manuscript, we present a comprehensive literature overview on the application of ovarian suppression with GnRHa during chemotherapy in patients with cancer by addressing preclinical and clinical data, as well as future perspectives in this field that upcoming research should focus on.

The Importance of Immunohistochemical Heterogeneous Expression of MMR Protein in Patients with Colorectal Cancer in Stage II and III of the Disease.

Background and objectives: In patients with colorectal cancer (CRC), heterogeneous expression of Mismatch repair (MMR) proteins can manifest itself in several different forms and is not such a rare phenomenon. Therefore, it is very important to recognize the nuclear expression of MMR proteins of different MMR status in order to avoid false positive or false negative results. The aim of this study was to determine the frequency and distribution of heterogeneous expression of MMR proteins in patients with stages II and III of the disease as well as its association with clinical, demographic and pathological characteristics of CRC in relation to proficient and deficient expression of MMR proteins. Material and Methods: The study included 104 cases of colorectal cancer obtained from surgical colectomy material in stages II and III of the disease. Results: From a total of 104 patients with colorectal cancer, immunohistochemical analysis of the expression of all four MMR proteins showed that heterogeneous expression of MMR proteins (as well as deficient immunoreactivity of tumor cells) was present in 12 cases, while proficient expression of MMR proteins was detected in 80 tumors. Conclusions: Our study showed that the only independent predictors of the loss of MMR protein expression were younger patient age and right-sided anatomical location of the tumor. The study also established the existence of heterogeneous expression of MMR proteins in a non-negligible percentage of CRCs (11.5%), where heterogeneous nuclear expression of MMR proteins was described in several different forms.

Developmental Characteristics of the Glomerular and Tubular Portion of the Nephron in the Human Foetal Kidney Cortex: Morphometrical and Immunohistochemical Analysis.

This study aimed to morphometrically examine the development of glomeruli and tubules in the kidney cortex of human foetuses at different gestational ages (GAs). We also investigated the expression of the proliferation marker Ki-67 and apoptosis-related markers Bcl-2 and Bax during nephrogenesis using immunohistochemistry. Kidney samples from 38 human foetuses of both sexes with GA ranging from 13 to 40 weeks were analysed. The samples were divided into 7 groups based on GA, each corresponding to 1 lunar month. Foetal kidneys showed a spatiotemporal gradient of nephron differentiation with the transient stages of nephron anlage located in the nephrogenic zone and immature nephrons located in the subjacent maturation zone. In the inner cortex, nephrons establish the morphological characteristics of definitive nephrons. The average area, perimeter, and Feret's diameter of the glomeruli formed within the kidney cortex gradually decreased up to a period of 29-32 weeks of gestation and subsequently increased until a period of 37-40 weeks. There was a weak negative correlation with GA. In contrast, the areal density of glomeruli increased up to a period of 21-24 weeks and then gradually decreased until a period of 37-40 weeks, showing a moderate negative correlation with GA. The average area of renal tubules slightly decreased until a period of 21-24 weeks of gestation and then gradually increased until a period of 36-40 weeks, showing a moderate positive correlation with GA. The average areal density of renal tubules increased significantly until a period of 21-24 weeks of gestation, remained relatively constant until a period of 33-36 weeks, and then increased significantly at 36-40 weeks. There was a strong positive correlation with GA. Our results showed that Ki-67 was expressed in numerous cells of the metanephric mesenchyme, pretubular aggregates, renal vesicles, comma-shaped bodies, and early S-shaped bodies. During subsequent development and the spatial expansion of nephrons towards the mature zone, the expression of Ki-67 was markedly reduced. Similarly, Bcl-2 was strongly expressed in induced nephrogenic progenitor cells, pretubular aggregates, renal vesicles, and comma-shaped bodies. As vascularisation and maturation of the nephron proceeded, Bcl-2 staining became less intense and limited to the parietal layer of the Bowman's capsule and renal tubules. Weak Bax expression was observed in individual scattered cells within segments of the nephrons at all developmental stages. In the mature zone, more intense Bax staining was observed in the renal tubules.

The hepatoprotective effect of aminoguanidine in acute liver injury caused by CCl4 in rats.

In this study, the hepatoprotective effect of aminoguanidine in acute liver damage caused by carbon tetrachloride-CCl4 at a dose of 1 mL/kg, i.p. was investigated in experimental rats. Ten days of preventive treatment with aminoguanidine before exposure to toxic CCl4, at a dose of 150 mg/kg, i.p., led to significant reduction in biochemical markers of acute liver injury-AST(p < 0.001), ALT (p < 0.01), SDH (p < 0.05) and reduction in pro-oxidative markers-H2O2 (p < 0.05), TOS (p < 0.01), TBARS, and LOOH (p < 0.001) in relation to rats treated only CCl4. Treatment with aminoguanidine resulted in a significant reduction in the consumption of antioxidant-GR (p < 0.01), GST, GPx, GSH (p < 0.001), and a decrease in pro-inflammatory-TNF-α (p < 0.01), IL-1ß, IL-6, NO and NGAL (p < 0.001) markers relative to animals exposed to CCl4 alone. Also, aminoguanidine pre-treatment leads to an increase in arginase activity (p < 0.001), and a decrease in citrulline concentration (p < 0.01), as well as polyamine catabolism enzyme activity-putrescin oxidase and spermine oxidase (p < 0.001) in comparison to the CCl4 group. Aminoguanidine led to a striking reduction of the necrotic field (p < 0.001), and a significant increase in the number of apoptotic hepatocytes (p < 0.001), as well as the proapoptotic markers-BAX and Caspase-3 (p < 0.05), compared to CCl4. The hepatoprotective mechanisms in CCl4 induce hepatotoxicity of aminoguanidine are based on the strong antioxidant effects, inhibition of pro-oxidative and pro-inflammatory mediators, as well as induction of damaged hepatocytes into apoptosis.

Lycopene and Caffeic Acid Phenethyl Ester Affect Caspase-3 Activity, but Do Not Alter the NO Pathway in Lung Tissue Damage Induced by Cisplatin.

INTRODUCTION: Antioxidants such as lycopene (LCP) and caffeic acid phenethyl ester (CAPE) represent ideal molecules for the treatment of different reactive oxygen species (ROS) associated disorders. Cisplatin is a chemotherapeutic agent, causing an increase in ROS and DNA damage, with numerous side effects, which include lung toxicity. In the presents study, we evaluated and mutually compared the potential of LCP and CAPE in preventing cisplatin-induced rat lung damage. METHODS: The study was done using pathohistological analysis and a panel of biochemical parameters that reflect lung oxidative tissue damage, inflammation, and apoptosis. RESULTS: The obtained results suggest that cisplatin (10 mg/kg) causes significant disturbances in the lung tissue morphology, followed by an increase in lipid peroxidization and protein modification. Also, a pronounced inflammatory response and cell apoptosis cascade activation was noted. Both LCP and CAPE were able to mitigate the changes, to a different extent, in oxidative damage and apoptosis progression induced by cisplatin. However, they both had limited effect on inflammation since they only prevented an increase in myeloperoxidase activity but had not been able to prevent the NO generation. CONCLUSION: It is hard to be exact in saying whether LCP or CAPE is better in preventing cis-platin-induced lung damage since they obviously possess different mechanisms of action.

Prognostic Value and Immunohistochemical Analysis of Mismatch Repair Deficiency in Patients with Stage II and III Colorectal Carcinoma-A Single-Center Study.

Background and objectives: Deficient mismatch repair (MMR) status is associated with good prognosis but poor therapeutic response to adjuvant chemotherapy in patients with colorectal cancer. However, there are some opposed arguments considering therapeutic outcomes in patients with evidenced MMR deficiency in colorectal cancer. The aim of the study was the investigation of prognostic value and immunohistochemical analysis of the MMR-deficiency tumors. Materials and Methods: The study enrolled 104 patients with resected stage II and III colorectal cancer samples from the period 2018-2019. Results: The tumors with deficient MMR status were significantly associated with age up to 50 years and right-sided localization (p < 0.001). During the follow-up period of 22.43 ± 6.66 months, 21 patients (20.2%) died, whereas 14 patients (13.5%) had relapses. The loss of mutL homologue 1/postmeiotic segregation increased 2 (MLH1/PMS2) expression, compared to proficient MMR tumors, was associated with shorter disease-free survival in patients with lymphovascular invasion (p < 0.05), perineural invasion (p < 0.01), stage III (p < 0.05) and high-grade tumor (p < 0.05). Conclusions: This retrospective pilot study of a single-center cohort of patients with stage II and III colorectal cancer highlights the clinical importance of using immunohistochemistry (IHC) analysis as a guide for diagnostic algorithm in a country with limited resources, but with a high prevalence of colorectal carcinoma in the young patients. MMR-deficiency tumors compared with proficient MMR colorectal cancer was not shown to be a significant predictor of disease-free and overall survival.

Do we really know how to overcome trastuzumab resistance in hormone sensitive metastatic breast cancer?

PURPOSE: This article focuses on how the status of hormone receptors (HR) influences the efficacy of trastuzumab in patients with metastatic HER2-positive breast cancer treated with first-line trastuzumab in combination with taxane-based chemotherapy. METHODS: A prospective study was carried out at the Clinic for Oncology, Clinical Centre in Nis, from January 2015 to until June 2018. A total of 121 patients were treated with first-line trastuzumab in combination with taxane-based chemotherapy. None of the patients from the HR-positive group received hormonotherapy after completion of chemotherapy with trastuzumab. RESULTS: Clinical benefit rate was present in 76% of the patients, including partial response (PR) in 37%, stable disease (SD) in 38%, and complete response (CR) in almost 8% of the patients. Progressive disease (PD) occurred in almost a quarter of the patients, i.e. 24%. Progression-free survival (PFS) in the entire group of patients amounted to 9 months, whereas overall survival (OS) was 30 months. PFS in the HR-negative tumor group was significantly longer (13 months) compared to 8 months in the HR-positive tumor group (p<0.0001; HR 0.49;95% CI 0.31-0.69). Furthermore, OS was significantly longer in the HR-negative tumor group (34 months), compared to 26 months in the HR-positive tumor group (p=0.0073, HR 0.57; 95% CI 0.36-0.90). CONCLUSIONS: These data indicate a different response to anti-HER2 therapy in patients with HER2+ metastatic breast cancer (MBC) according to HR status, thus emphasizing that ER most likely represents an escape pathway for the response to anti-HER2 target therapy and vice versa. Combining hormonotherapy with anti-HER2 therapy surely represents a promising strategy which could help overcome resistance to trastuzumab and other anti-HER2 agents.

Granulocyte-macrophage colony-stimulating factor as a mediator of autoimmunity in multiple sclerosis.

Autoreactive, myelin-specific, CD4+ T cells have a central role in multiple sclerosis (MS) pathogenesis; however the exact phenotype characteristics of these cells remain elusive. Recently, granulocyte-macrophage colony-stimulating factor (GM-CSF) expression has emerged as the main pathological signature of the encephalogenicity in both T and B cell compartment. In this review we have summarized the current data supporting GM-CSF relevance in MS pathophysiology, in the context of both immunomodulatory and neuroinflammatory processes; as well as the potential cellular sources of this stimulating factor, including different T and B cell subsets.

Ten years of using adjuvant trastuzumab in breast cancer in Serbia - Single institution experience.

PURPOSE: The purpose of this study was to determinate disease-free interval (DFI) and overall survival (OS) in HER2-positive breast cancer patients who received adjuvant trastuzumab at the University Clinic of Nis, Serbia, and to investigate the influence of clinicopathological and biological characteristics of the tumor on prognosis. The second aim was to determinate the most frequent cause for the treatment discontinuation, recurrence rate, as well as the site of most common localization of the first recurrence of disease. METHODS: This research was conducted as a retrospective study at the University Oncology Clinic, Clinical Centre in Nis. The study included 238 patients who were operated and treated for HER2-positive breast cancer between January 1st, 2007 to September 30th, 2012 and followed up until December 31st, 2016. Trastuzumab was administered concurrently with taxanes, if administered, or after the completed anthracycline-based chemotherapy. RESULTS: After a median follow up of 69 months the 5-year DFI was 65.9% and 5-year OS was 81.8% and, as expected, significantly longer in the group of patients with smaller tumors, a smaller number of positive axillary lymph nodes, as well as a lower stage of disease (p<0.0001). Patients older than 65 years had a longer DFI compared to the 45-65 and under 45 age groups of patients (p=0.01). No statistical significance was found in the length of DFI in relation to the histological tumor subtype, tumor grade, or the status of hormone receptors. Unlike DFI, a longer OS was recorded in the group of patients with lower tumor grade (p=0.03) and there was no statistically significant difference in survival regarding the age of patients (p=0.07). Recurrence occurred in approximately one third of the patients (38.23%), mostly in the form of local recurrence. Adjuvant therapy with trastuzumab was not completely carried out in 18.49% of the patients, the most common reason being the progression of disease. CONCLUSIONS: A long median follow up period of 69 months indicated that anti-HER2 monoclonal antibody trastuzumab, after anthracycline-based chemotherapy or concurrently with taxanes, is efficient and safe in treating early breast cancer.

Markers of proliferation and cytokeratins in the differential diagnosis of jaw cysts.

We conducted a retrospective study to analyze the histologic and immunohistochemical findings in three main types of odontogenic cyst. We studied 90 archived cystic jaw lesions: 30 dentigerous cysts, 30 keratocystic odontogenic tumors, and 30 radicular cysts. The cyst types were identified on the basis of clinical, radiologic, and histopathologic findings. Immunohistochemical analyses included staining with Ki-67, p53, epidermal growth factor receptor (EGFR), cytokeratin (CK) 8, CK14, CK17, and CK18. Cell immunopositivity was evaluated for the entire epithelium. The criteria for Ki-67 and p53 positivity were dense and/or faint nuclear staining, and cells were considered EGFR-positive if they exhibited membrane staining and/or cytoplasm staining. For the cytokeratins, cells exhibiting cytoplasm staining were considered positive. Five representative fields of each lesion were selected and identified in each of the Ki-67- and p53-stained slides. We found a statistically significant difference in the ratio of Ki-67-positive cells in the entire layer between the keratocystic odontogenic tumors and both the dentigerous cysts and the radicular cysts. A statistically significant difference was observed in the ratio of p53-positive cells between the keratocystic odontogenic tumors and the radicular cysts. Cytokeratins proved to be useful in differentiating radicular cysts from other types of cystic jaw lesions because of their CK8-positive and CK17-negative immunolabeling.

Central mucoepidermoid carcinoma of the mandible ­ A case report.

Introduction: Mucoepidermoid carcinoma, compared to other tumors of salivary glands, occurs in 5­10% of cases. Histopathologically, it is divided into a well differentiated tumor that is of low-grade of malignancy, and a medium and poorly differentiated tumor of high grade of malignancy. Central mucoepidermoid carcinoma (CMEC) of the mandible was firstly described by Lepp in 1936, on a 66-year-old female patient. CMEC is characterized by atypical clinical image and radiological manifestation. Case Outline: A 55-year-old female patient was examined at the Clinic of Dentistry in Nis, Serbia, with anamnestic data regarding the presence of painless swelling in the right side of the mandible. Considering the histopathological results and presence of enlarged lymph nodes, right hemimandibulectomy and tumour excision from pterygomandibular space followed by supraomohyoid neck dissection was done. In due course, postoperative radiotherapy was applied (60 Gy) Conclusion: CMEC represents a rare tumor, characterized by local tissue destruction and ability to metastasize. Initial biopsy represented the key in preoperative planing. Radical excision with neck lymph node dissection followed by postoperative radiotherapy in our case represent a successful method of treating CMEC of the mandible.

Young age and pathological features predict breast cancer outcome - report from a dual Institution experience in Serbia.

PURPOSE: The aim of this study was to investigate the influence of clinicopathological and biological characteristics on prognosis, disease free survival (DFS) and overall survival (OS), of very young patients (≤35 years of age) with breast cancer. METHODS: We retrospectively collected information of 150 women diagnosed with breast cancer, aged ≤35 years, who were operated and treated at two University Hospitals in Serbia between January 2009 and February 2011. RESULTS: After a median follow up of 44 months patients ≤30 had shorter DFS and OS compared to patients aged 31-35 years (p=0.004 and p=0.037, respectively). The differences in DFS and OS were significant with decreased survival associated with higher tumor grade (p=0.005 and p=0.0001, respectively). Tumor size and number of positive nodes were predictors of outcome with decreased survival associated with higher tumor size (p=0.0019 for DFS and p<0.0001 for OS) and increasing number of nodes (p<0.0001 for both). HER 2 receptor did not seem to have a prognostic influence while patients with hormonal receptors (HRs) positive tumors had a better DFS (p=0.034) and OS (p=0.046) than those with HRs negative tumors. In univariate survival analysis, a significant difference in DFS (p=0.0003) and OS (p=0.0003) was found between patients with vs without lymphovascular invasion (LVI). CONCLUSION: Diagnosis of breast cancer at very young age (<30) was associated with increased risk of death and shorter DFS than women aged 31-35. Negative impact on survival was seen in patients with presence of LVI, negative HRs and higher grade and stage at the time of presentation.

Asymptomatic flow of Rosai-Dorfman disease.

INTRODUCTION: Sinus histiocytosis with massive lymphadenopathy is a rare benign self-limiting disease of unknown etiology. The salivary gland involvement, indicating the extranodal character of the disease, often presents a diagnostic dilemma requiring immunohistochemical staining of surgically removed tumor to confirm the diagnosis. CASE REPORT: We report a 43-year-old man presented with an asymptomatic mass in the left mandibular angle. On physical examination, the lesion was described as a painless, mobile, firm-elastic consistency nodule, which measured 4 x 3 cm in diameter, with normal overlying skin. A mass with the same characteristics, dimensions 2 x 2 cm, was also noted in the right parotid region. No other changes in regional lymph nodes were detected. On macroscopic examination the lesion was firm, multilobulated, yellowish and rounded, while on microscopic examination the lesion was composed almost entirely of polygonal histiocytes with abundant cytoplasm, emperipolesis, plasma cells arranged in sheets, and lymphocytes scattered or within clusters. The observed histiocytes were found to be CD68 and S100 protein positive. CONCLUSION: Rosai-Dorfman disease is a beningn and frequently overlooked clinical and pathological entity that may be misinterpreted as a neoplastic disease.

Bilateral giant angiomyolipomas revealed after massive retroperitoneal hemorrhage - A case report.

INTRODUCTION: Angiomyolipomas (AML) are benign neoplasms composed of fat, smooth muscle and thick-walled blood vessels in varying proportions. These tumors have a significant female predominance. CASE REPORT: We reported a 61-year-old man with spontaneous rupture of AML. Computerized tomography revealed a change in morphology of both kidneys. Multiple lesions of fat density with dilated blood vessels were found in the left kidney. The right retroperitoneum was obliterated with a giant heterogeneous mass originating from the right kidney with a massive hemorrhage, active extravasations, compression of inferior the vena cava and intraperitoneal collections. After radical nephrectomy, histological examination revealed that the tumor was composed of relative proportions of fat, smooth muscle and blood vessels. We incidentally found small renal adenoma. CONCLUSION: The true nature of AML is unclear, but they are usually classified as hamartomas. Angiomyolipomas are generally benign lesions, although the epithelioid angiomyolipoma, a subtype that occurs in about 3% of cases, can behavior aggressively.

Clinical benefit of cetuximab and prognostic value of cetuximab-related skin toxicity in metastatic colorectal cancer: a single institution analysis.

PURPOSE: To evaluate the clinical benefits of cetuximab (CTX) and the prognostic value of CTX-related skin toxicity in metastatic colorectal cancer (mCRC) patients. METHODS: Sixty patients were tested for KRAS mutation at the Department of Oncology, Clinical Centre Nis. We assessed 34 wild-type KRAS mCRC patients treated with CTX. All of them were refractory to prior fluoropyrimidine, oxaliplatin and irinotecan-based regimens. The maximum grade skin toxicity according to treatment cycle was analyzed. Skin toxicity was grouped into clinically non-relevant skin toxicity (grade 0-1: Group 1) and clinically relevant skin toxicity (grade 2-4: Group 2). RESULTS: Ten out of 33 patients (30.30%) achieved partial response (PR). Eight additional patients (24.24%) showed stable disease (SD), whereas 15 (45.45%) had disease progression (PD). No patient achieved complete response (CR). Overall response rate (ORR) was 30.30%, whereas the disease control rate (DCR) was 54.54%.The median progression free survival (PFS) was 14 weeks. Some degree of skin toxicity was observed in 79.41% (27/34) of the patients. Clinically non-relevant skin toxicity was observed in 50% (17/34), and clinically relevant in 50 % (17/34) of the patients. Grade 4 skin toxicity was documented in 1 patient. The mean PFS in Group 1 was 12.65±5.59 weeks and in Group 2 22.82±12.16 (p<0.05). The results showed that grade 2-4 skin toxicity was associated with significantly better response to treatment than skin toxicity grade 0-1, with regard to ORR (80.00 vs 20.00%; p<0.05) and DCR ( 66.66 vs 33.33%; p<0.05). CONCLUSION: Cetuximab has clinical benefit when given alone or in combination with irinotecan in patients with irinotecan-refractory CRC. Skin toxicity was one of the predictors of response and it was in line with what was expected.

A rare case of retroperitoneal malignant Triton tumor invading renal vein and small intestine.

INTRODUCTION: Malignant Triton tumor is a very rare malignant peripheral nerve sheath tumor with rhabdomyosarcomatous differentiation. Most of those tumors occur in patients with von Recklinghausen's disease or as a late complication of irradiation and commonly seen in the head, neck, extremities and trunk. CASE REPORT: We reported retroperitoneal malignant Triton tumor in a 57-year-old female patient. Skin lesions were not present, and there was no family history of neurofibromatosis or previous irradiation. The presented case is one of a few recorded in the specialized literature that occurs in the retroperitoneal space in sporadic form. In this case, tumor consisted of a multilobular mass was in close relation with the abdominal aorta and inferior vena cava and involved the renal vein with gross invasion of the small intestine. The patient underwent total resection of the tumor and left nefrectomy was performed. The small intestine 10 cm in length was also resected and end-to-end anastomosis was conducted. The postoperative course was uneventful and the patient was discharged from the hospital ten days after the surgery. CONCLUSION: Diagnostically, it is crucial to recognize this uncommon histological variant because malignant Triton tumor has a worse prognosis than classic malignant peripheral nerve sheath tumor does. The use of the immunohistochemistry is essential in making the correct diagnosis. Only appropriate pathological evaluation supported by immunostaining with S-100 protein and desmin confirmed the diagnosis. Aggressive surgical management treatment improves the prognosis of such cases with adjuvant radiotherapy.