Background: Struma ovarii is a rare ovarian neoplasm, which contains thyroid tissue. It accounts for less than 5% of ovarian teratomas. These are mostly benign, occurring between 40 years and 60 years of age. Clinical and radiological features are inconclusive and mostly it is diagnosed by histopathology. About 5–8% cases have hyperthyroidism. Cystic struma ovarii is very rare with only 25 cases reported till now. It creates confusion in diagnosis, as even in histopathology, the cells are mostly like those resembling other cystic ovarian tumors with minimal thyroid follicles.
Case description: A 20-year-old girl came with complaints of abdominal discomfort and difficulty in squatting and lying supine. Clinically, a 28-week-size cystic tumor was palpated. Ultrasound showed features of a cystic benign tumor. Tumor markers were normal. Laparoscopic cystectomy was done. Histopathology showed cystic struma ovarii. At 6-month follow-up, the patient has been doing well.
Conclusion: Cystic struma ovarii is a rare diagnosis. Clinical, biochemical, and radiological features do not help. A careful and keen pathological examination is necessary so that thyroid follicles are not left while viewing. There is no clear consensus on follow-up of these patients, but benign tumors usually do not need extensive follow-up.
Clinical significance: It is a rare tumor and a good histopathological diagnosis is needed. Cystic tumors should be carefully examined. A proper correlation between clinical, biochemical, radiological, intraoperative, and histopathological findings may help us to consider this diagnosis when we get similar cases.
Robins, Cotran. Pathologic Basis of Disease Kumar V, Abbas A, Fausto N, ed. 9th ed., Publisher Elsevier India Ltd; 2015. p. 1030.
Prat J, Nogales FF, Cao D, et al. Monodermal teratomas and somatic type tumors arising from a dermoid cyst Kurman RJ, Carcangiu ML, Herrington CS, et al., ed. WHO Classification of Tumours of Female Reproductive Organs. Lyon: IARC Press; 2014. pp. 63–66.
Kondi-Pafiti A, Mayrigiannaki P, Grigoriadid Ch, et al. Monodermal teratomas (struma ovarii). Clinicopathological characteristics of 11 cases and literature review. Eur J Gynaecol Oncol 2011;32:657.
Yoo SC, Chang KH, Lyu MO, et al. Clinical characteristics of struma ovarii. J Gynecol Oncol 2008;19(2):135. DOI: 10.3802/jgo.2008.19.2.135.
Karuna V, Gupta P, Verma N, et al. Uncommon tumor with rare variants: cystic struma ovarii – a case report with review of literature. Medical Journal of Dr DY Patil Vidyapeeth 2019;12(6):516. DOI: 10.4103/mjdrdypu.mjdrdypu_182_18.
Jesus PC, Filomena MC, Flávia FL, et al. Hypothyroidism following struma ovarii tumor resection: a case report. Rev Hosp Clin 2002;57(1):1–3. DOI: 10.1590/S0041-87812002000100001.
Kraemer B, Grischke EM, Staebler A, et al. Laparoscopic excision of malignant struma ovarii and 1 year follow-up without further treatment. Fertil Steril 2011;95(6):2124.e9. DOI: 10.1016/j.fertnstert.2010.12.047.
De Simone CP, Lele SM, Modesitt SC. Malignant struma ovarii: a case report and analysis of cases reported in the literature with focus on survival and 1131 therapy. Gynecol Oncol 2003;89(3):543. DOI: 10.1016/S0090-8258(03)00141-0.
Hemalatha AL, Abilash SC, Girish M. Cystic struma ovarii – a pathological rarity and diagnostic enigma. Arch Cytol Histopathol Res 2017;2:12–14.
Manini C, Magistris A, Puopolo M, et al. Cystic struma ovarii: a report of three cases. Pathologica 2010;102:36–38.
Szyfelbein WM, Young RH, Scully. RE. Cystic struma ovarii: a frequently unrecognized tumor. a report of 20 cases. Am J Surg Pathol 1994;18(8):785–788. DOI: 10.1097/00000478-199408000-00004.
Savelli L, Testa AC, Timmerman D, et al. Imaging of gynecological disease (4): clinical and ultrasound characteristics of struma ovarii. Ultrasound Obstet Gynecol 2008;32(2):210–219. DOI: 10.1002/uog.5396.
Matsuki M, Kaji Y, Matsuo M, et al. Struma ovarii: MRI findings. Br J Radiol 2000;73(865):87–90. DOI: 10.1259/bjr.73.865.10721328.
Carvalho RB, Cintra ML, Matos PS, et al. Cystic struma ovarii: a rare presentation of an infrequent tumor. Sao Paulo Med J/Rev Paul Med 2000;118(1):17–20. DOI: 10.1590/S1516-31802000000100005.
Mui MP, Tam KF, Tam FK, et al. Coexistence of struma ovarii with marked ascites and elevated CA-125 levels: case report and literature review. Arch Gynecol Obstet 2009;279(5):753–757. DOI: 10.1007/s00404-008-0794-1.
Cooper DS, Ridgway EC, Maloof F. Unusual types of hyperthyroidism. Clin Endocrinol Metab 1978;7(1):199–220. DOI: 10.1016/S0300-595X(78)80043-7.
Nor NBMd, Kusumoto T, Inoue S, et al. Three cases of struma ovarii underwent laparoscopic surgery with definite preoperative diagnosis. Acta Med Okayama 2013;67:191–195.
Volpi E, Ferrero A, Nasi PG, et al. Malignant struma ovarii: a case report of laparoscopic management. Gynecol Oncol 2003;90(1):191–194. DOI: 10.1016/S0090-8258(03)00142-2.