Malignant transformation within a dermoid cyst: a case report and literature review

Malignant Transformation of a Filum Terminale Dermoid Tumor into Adenocarcinoma

BACKGROUND

Intraspinal dermoid tumors are usually rare benign growths that occur as a result of defects during neural tube formation. They make up less than 1% of tumors in the spine and are associated with spinal dysraphisms or sinus tracts. Although rare, malignant transformation into squamous cell carcinoma has been previously reported. Malignant transformation into adenocarcinoma, however, represents a novel phenotypic differentiation pattern that is hitherto undescribed.

CASE DESCRIPTION

A 45-year-old woman presented with acute symptoms of cauda equina syndrome. Imaging of the spine revealed a large intradural sacral mass. The lesion was surgically resected with pathology revealing a dermoid tumor with malignant transformation into adenocarcinoma. Metastatic workup revealed no other suspicious lesions. The patient had an uneventful postoperative course, gradually regaining micturition control.

CONCLUSIONS

Dermoid tumors, also known as benign cystic teratoma or mature teratoma, are usually benign congenital tumors comprising epithelial cells that arise from displaced embryonic ectoderm and mesoderm during neural tube formation. Although extremely rare, malignant transformation into squamous cell carcinoma has been reported. This case represents the first report of an intraspinal dermoid tumor transforming into adenocarcinoma. A comprehensive histopathologic analysis is key to identifying the lesion and guiding postsurgical management.

Squamous cell carcinoma transformation in mature cystic teratoma of the ovary: a systematic review

BACKGROUND

0.17-2% of mature cystic teratoma of the ovary (MCTO) undergo malignant transformation, of which 80% are squamous cell carcinoma (SCC) transformation in MCTO. We aim to investigate the clinical characteristics and treatment of SCC transformation in MCTO METHODS: We systematically searched PubMed database and individual patient data about SCC transformation in MCTO were extracted. The published cases were combined with 6 cases of SCC transformation in MCTO from Qilu Hospital, Shandong University.

RESULTS

The incidence of SCC transformation in MCTO was 0.3%. A total of 435 cases of SCC transformation in MCTO were enrolled in the analysis. The mean age of diagnosis was 53.5 (range 19-87) years old. The most common clinical manifestations were abdominal pain (47.3%) and abdominal mass (26.0%). StageI,II, III and IV accounted for 50.0, 18.8, 26.8 and 4.4% of all cases, respectively. Patients with stage I had significantly better prognosis than stage II, III and IV patients (P < 0.01). Hysterectomy can improve overall survival (P < 0.01). For patients younger than 45 years old with stageIA orIC, there was no difference in mortality between fertility-sparing and radical surgery (P = 1.00). Adjuvant chemotherapy can improve survival in patients with advanced stage (P = 0.02), and chemotherapy with platinum was related to better prognosis (P = 0.02).

CONCLUSION

SCC transformation in MCTO is a rare malignancy mainly occurs in older age. FIGO stage is an independent prognostic factor. Hysterectomy and platinum-based chemotherapy are associated with better survival. Fertility-sparing surgery is feasible for young patients with early stage.

Large Sublingual Dermoid Cyst: A Case of Mandibular Prognathism

Dermoid cysts are unusual neoplasms and can occur in every part of the human body. They represent only 6.9% of all dermoid cysts in the head and neck region; in the oral cavity, the incidence is low, approximately 1.6% of all dermoid cysts. Our aim is to present an unusual case of a large sublingual dermoid cyst with mandibular prognathism caused by cyst growth. We reported a case of a large sublingual dermoid cyst in an 8-year-old female patient. A bibliographic research from 1937 to 2013 is reviewed and we found only three cases of mandibular deformity, of which only one was a dermoid cyst of the floor of the mouth. Removal of dermoid cysts of the floor of the mouth should be completed as early as detected, especially in newborns and infants when osseous growth abnormalities could result if removal is delayed.

A series of malignant ovarian cancers arising from within a mature cystic teratoma: a single institution experience

BACKGROUND

Mature cystic teratoma (MCT) is the most common germ cell tumor. It accounts for 10% to 20% of all ovarian masses. The likelihood of malignancy arising from within an MCT is low, and prognosis is poor.

METHODS

A single-institution retrospective chart review was completed of all cases of MCT from 2004 to 2012. Multiple variables were examined including procedure performed, residual disease after surgery, surgical stage, histologic type, site of primary disease, date of recurrence, whether or not adjuvant chemotherapy was given, and whether or not there was death secondary to disease.

RESULTS

During the study period, 1.2% of MCTs exhibited malignant transformation. The average age at presentation was 53.7 years. Mean follow-up time was 23 months. The most common presenting symptoms were bloating and abdominal pain. The average tumor size was 18 cm. Of note, 33% of cases were at least surgical stage IIIC at the time of presentation, whereas the remainder were stage IC or lower. Four (44.4%) of the 9 cases were identified as mucinous adenocarcinoma in addition to 1 case each of malignant melanoma, squamous cell carcinoma, and poorly differentiated adenocarcinoma. Only 1 patient experienced recurrence. One patient had a known MCT that was being managed expectantly and exhibited malignant transformation to a mucinous adenocarcinoma.

CONCLUSIONS

A large ovarian mass that is suspected to be a mature teratoma should be managed more aggressively in older patients. Our data suggest that although malignancy arising from mature teratomas is rare, it is more likely when patients are older than 40 years, the mass is greater than 18 cm, and there is any suspicion for a mucinous tumor. Like most ovarian tumors, these tumors most often present at later stages and, thus, can be difficult to treat. It is unclear what role chemotherapy or radiation plays in the management of these tumors.

Conditional inactivation of p53 in mouse ovarian surface epithelium does not alter MIS driven Smad2-dominant negative epithelium-lined inclusion cysts or teratomas

Epithelial ovarian cancer is the most lethal gynecological malignancy among US women. The etiology of this disease, although poorly understood, may involve the ovarian surface epithelium or the epithelium of the fallopian tube fimbriae as the progenitor cell. Disruptions in the transforming growth factor beta (TGFβ) pathway and p53 are frequently found in chemotherapy-resistant serous ovarian tumors. Transgenic mice expressing a dominant negative form of Smad2 (Smad2DN), a downstream transcription factor of the TGFβ signaling pathway, targeted to tissues of the reproductive tract were created on a FVB background. These mice developed epithelium-lined inclusion cysts, a potential precursor lesion to ovarian cancer, which morphologically resembled oviductal epithelium but exhibited protein expression more closely resembling the ovarian surface epithelium. An additional genetic “hit” of p53 deletion was predicted to result in ovarian tumors. Tissue specific deletion of p53 in the ovaries and oviducts alone was attempted through intrabursal or intraoviductal injection of Cre-recombinase expressing adenovirus (AdCreGFP) into p53^flox/flox mice. Ovarian bursal cysts were detected in some mice 6 months after intrabursal injection. No pathological abnormalities were detected in mice with intraoviductal injections, which may be related to decreased infectivity of the oviductal epithelium with adenovirus as compared to the ovarian surface epithelium. Bitransgenic mice, expressing both the Smad2DN transgene and p53^flox/flox, were then exposed to AdCreGFP in the bursa and oviductal lumen. These mice did not develop any additional phenotypes. Exposure to AdCreGFP is not an effective methodology for conditional deletion of floxed genes in oviductal epithelium and tissue specific promoters should be employed in future mouse models of the disease. In addition, a novel phenotype was observed in mice with high expression of the Smad2DN transgene as validated through qPCR analysis, characterized by teratoma-like lesions implicating Smad signaling in teratoma development.

Proteomic analysis of mesenchymal stem-like cells derived from ovarian teratoma: potential role of glutathione S-transferase M2 in ovarian teratoma

Ovarian teratoma is a dermoid cyst in the ovary that contains mature tissues such as hair, teeth, bone, thyroid, etc. To understand the molecular mechanisms of ovarian teratoma growth, a comparative proteomic analysis was undertaken using mesenchymal stem cell-like cells (MSCLCs) isolated from normal human ovarian or teratoma tissues. Both normal ovarian and teratoma MSCLCs expressed stem cell markers OCT4 and NANOG, and were negatively staining with the senescence-associated (SA) β-galactosidase. Furthermore, teratoma MSCLCs had higher proliferation and colony formation rates, with more angiogenic property than that of normal MSCLCs. Proteomic study revealed that 17 proteins had the expression changes over eightfold in ovarian teratoma MSCLCs compared with normal control. Interestingly, among them, GSTM2 was strongly expressed in teratoma MSCLCs. Moreover, overexpressed GSTM2 in the teratoma was associated with downregulation of p38 MAPK and activation of AKT and survivin. Taken together, these findings suggest that that ovarian teratoma MSCLCs have a higher potency for proliferation and angiogenesis and GSTM2 appears to be involved in the regulation of other survival genes.

Squamous-cell carcinoma in mature cystic teratoma of the ovary: systematic review and analysis of published data

Up to a quarter of ovarian masses originate from germ cells, and many of these are mature cystic teratomas. The secondary development of malignancy is a rare but well-known phenomenon in patients with ovarian teratomas. Squamous-cell carcinoma accounts for 80% of secondary malignant transformations of ovarian teratomas. We aimed to do an up-to-date systematic review of this rare malignant transformation. 64 suitable studies provided information on 277 patients. Squamous-cell carcinoma in mature cystic teratoma was mainly found in women aged more than 50 years, with high concentrations of squamous-cell-carcinoma antigen and cancer antigen CA125, and with ovarian tumours more than 100 mm in size. Patients with FIGO stage Ia tumours had better survival than those with more advanced disease. Complete resection together with hysterectomy, bilateral salpingo-oophorectomy and lymphadenectomy for patients with advanced disease, followed by adjuvant chemotherapy with an alkylating drug was associated with higher survival, radiotherapy was not. We make proposals for investigation and treatment of this rare disorder.