A rare presentation of small diaphragmatic epidermoid cyst with extremely elevated serum CA19-9 level

Abstract

Epidermoid cysts are rare lesions that can occur anywhere in the body. They are associated with elevated serum levels of CA 19-9. The spleen represents the most common site of intra-abdominal localisation. Only two cases of diaphragmatic epidermoid cyst are reported in the literature. We present the case of a 61-year-old woman with a small suprasplenic subdiaphragmatic cyst discovered during the investigation of left flank pain. The establishment of an adequate diagnosis was challenging due to the difficulty in specifying the exact localisation of the cyst, the extremely elevated CA 19-9 level of 19,000 and the high uptake on 18-fluoro-2-deoxy-D-glucose positron emission tomography. The definitive diagnosis followed complete surgical excision. Intra-abdominal epidermoid cysts are usually discovered incidentally on imaging for another reason. The cyst is lined by squamous epithelium responsible for the secretion of CA 19-9. The elevation of serum CA 19-9 is due to small rupture or increased intraluminal pressure followed by diffusion to the bloodstream. Surgery with en-bloc resection represents the optimal treatment to avoid any risk of recurrence. The definitive diagnosis is established by demonstrating positive immunohistopathological staining of epithelial cell to CA 19.9.

Rare finding of a symptomatic epidermoid cyst of the diaphragm – a case report

“…Histological features of epidermoid cysts include squamous epithelium and positive staining for CK [ 2 ], as was present in this case. Unlike a dermoid cyst, skin adnexae like hair follicles and sebaceous glands were absent.…”

“…Features in the clinical history or imaging may help characterize a diaphragmatic cyst to guide management, but in this case the diagnosis of an epidermoid cyst could not be made until after surgery. Epidermoid cysts of the diaphragm are very rare with three prior cases reported in the literature [ 2 ].…”

“…On histological grounds and by analogy with cutaneous epidermoid cysts, they are presumed to be benign. Raised CA19-9 levels which returned to normal levels after resection of benign epidermoid cysts has been described [ 2 , 12 ], suggesting that this serum marker may not help differentiate malignant from benign cysts.…”

“…Laparoscopic or open surgery can be considered for cystic lesions in this region if symptomatic or if concerned about a non-benign pathology on radiological or clinical grounds [ 13 ]. It has been suggested that cysts >5 cm in size may be at risk of rupture [ 2 ]. This case posed a diagnostic challenge, given the lack of specific radiological or clinical features.…”

Significantly Elevated CA 19-9 after COVID-19 Vaccination and Literature Review of Non-Cancerous Cases with CA 19-9 > 1000 U/mL

“…Herein, we report six cases of patients with AIP, causing the elevation of CA 19-9 ranging from 1950 U/mL to 12,000 U/mL, and a case of a patient with liver steatosis and an increased CA 19-9 value to 1930 U/mL. When considering differential diagnosis due to the low specificity of tumor markers and lack of obvious radiological image, various diseases should be taken into consideration [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 68 , 69 ]; however, a mildly increased dimension of the pancreas in MRI with areas of fluid signals could correspond to past AIP that induced increased CA 19-9. According to the literature, about 25% of patients with AIP show values of CA 19-9 > 37 U/mL, and only around 12.2% of them show elevated levels > 100 U/mL [ 70 ].…”