Ectopic salivary gland tissue in a Rathke’s cleft cyst

The presence of salivary gland tissue in the sella turcica has rarely been reported, mainly after pituitary examination at autopsy. Only five symptomatic cases have previously been described, mainly associated with Rathke’s cleft cyst. We report a 17-year-old boy presenting with headaches and hyperprolactinemia. The MRI showed a 19 mm sellar mass that at surgery revealed as a cystic lesion filled with mucinous fluid. The histological examination documented the presence of ectopic salivary gland tissue in the wall of a Rathke’s cleft cyst. The present report focuses on the possible pitfalls when dealing with unusual sellar lesions, and the need of increased awareness of this rare condition.     

Müllerian adenosarcoma with a neuroectodermal component associated with an endometriotic cyst of the ovary: a case report

Reported here is a case of Müllerian adenosarcoma of the ovary which contained a primitive neuroectodermal tissue component within the stroma. The adenosarcoma coexisted with clear cell adenocarcinoma in an endometriotic cyst. The patient was a 33-year-old woman with a large unilocular endometriotic cyst of the right ovary. On the internal wall of the cyst, both a plaque-like protrusion with a papillary surface and a dome-like mural nodule were noted. The former exhibited features of Müllerian adenosarcoma, and the latter showed those of clear cell adenocarcinoma. In the deeper portion of adenosarcoma, teratoma-like tissue which contained various tissue components including primitive neuroectodermal tissue was found. The presence of primitive neuroectodermal tissue in the stroma of adenosarcoma suggested the diagnosis of 'adenosarcoma with neuroectodermal differentiation' ('teratoid adenosarcoma'), although the possibility of the incidental occurrence of an immature teratoma could not be completely excluded.     

Ciliated hepatic cyst without smooth muscle layer: A variant of ciliated hepatic foregut cyst?

The ciliated hepatic foregut cyst (CHFC) is a rare lesion that may arise from remnants of the embryonic foregut. Its wall is lined by pseudostratified ciliated columnar epithelium, and is characterized by the presence of bundles of smooth muscle. Herein is presented two cases of ciliated hepatic cyst without smooth muscle layer. One case was an incidental autopsy finding, and the other was a surgically resected cystic lesion of the liver. Both cysts were <2.0 cm in diameter, and were located subcapusularly in the medial segment (S4) of the liver. The histological appearance of the two cases was identical. They had an epithelial lining of ciliated pseudostratified cells with occasional goblet cells, and lacked a smooth muscle layer, as shown by the actin immunostaining. The lining epithelium contained cells positive for immunohistochemical staining of surfactant apoprotein A, suggesting the embryonic foregut origin of the cysts and differentiation toward bronchiolar structures, rather than ciliated metaplasia of the epithelium of the simple (cholangiogenic) cyst. It is considered that ciliated hepatic cysts of the present case are a rare histological variant of CHFC where the smooth muscle layer is inconspicuous or absent.     

Reduplication cyst of appendix with mucinous carcinoma and Müllerian metaplasia: a case report

This report describes a case of mucinous carcinoma and Müllerian metaplasia arising within an appendiceal duplication cyst found incidentally during an emergency Caesarian section. Intestinal duplication cysts are rare and although there are occasional reports of malignant transformation, this is the first case where Müllerian metaplasia was found concurrently with a malignancy. There was no previous history of endometriosis and no other abnormalities were found at surgery. Treatment included surgical excision. The patient is alive and well two years after removal of the cyst.     

Immunohistochemical analysis of retroperitoneal Müllerian cyst

Retroperitoneal cysts are uncommon diseases, and benign nonneoplastic Müllerian cysts are extremely rare among the known cases. We report a case of a 35-year-old woman with a retroperitoneal Müllerian cyst with the tubal type of epithelium. The patient presented with a large (20 cm in diameter), palpable abdominal mass. This multilocular cystic mass was resected from the retroperitoneum between the descending colon and the left renal fascia. Histologically, it was lined by monolayered low-cuboidal to columnar cells without atypia that resembled tubal epithelium, including cilia. Loose fibrous tissue and incomplete smooth muscle bundles were identified beneath the epithelium of the lining. Immunohistochemical tests showed that the lining cells were strongly positive for cytokeratins (CKs) (polyclonal, 7, 18, CAM 5.2, AE1/AE3), epithelial membrane antigen, cancer antigen 125, progesterone receptor, and estrogen receptor. The lining cells were also occasionally weakly positive for CK5/6. They tested negative for CK20, carcinoembryonic antigen, calretinin, and CD 10.     

Is formal decompression necessary for parameniscal cysts associated with meniscal tears?

BackgroundMeniscal tears and associated parameniscal cysts have good outcomes after partial meniscectomy and cyst evacuation. Good outcomes have been noted after partial meniscectomy with recurrent cysts. This investigation asks if partial meniscectomy without meniscal cyst decompression is sufficient for positive patient outcome.MethodsSixteen patients treated between 2005 and 2010 for a meniscal cyst and concomitant meniscal tear. Inclusion criteria were meniscal tear and parameniscal cyst per MRI, no prior surgery on the affected knee, and Outerbridge classification of I/II. Two patients were excluded. Fourteen patients completed the study until final follow-up. Lysholm knee scores were documented at 6 months post-operatively and at final follow-up. Re-evaluation or second surgery of the treated knee was documented.ResultsEight lateral cysts and six medial cysts were diagnosed. Eight cysts were associated with a horizontal cleavage tear, while six menisci had a complex tear with a horizontal cleavage component. The average cyst size was 1.3 cm (0.5 to 3.5) at the largest diameter. At 6 months, the average Lysholm knee score was 94.1. At mean 5 years, the average score was 89.1. Patients with medial cysts, cysts greater than 1.0 cm, horizontal cleavage tears, or without simultaneous chondroplasty scored higher in the short and medium-term than their respective counterparts.ConclusionsExcellent short and medium-term outcomes can be achieved following partial meniscectomy without cyst decompression for patients with meniscal cysts and associated meniscal tears.Level of evidenceLevel IV     

Investigating meniscal symptoms in patients with knee osteoarthritis—Is MRI an unnecessary investigation?

The aim of this study was to evaluate the relationship between radiographic knee osteoarthritis and the presence of a relevant meniscal tear detected on MRI in symptomatic patients over the age of 60.Seventy seven patients over the age of 60 who had been investigated with a knee MRI over a 1-year period were identified. Sixty patients had a full set of data available for analysis. Their plain radiographs were blindly graded for osteoarthritis using the Kellgren-Lawrence (K-L) scale. The indications for the MRI were subdivided into: meniscal symptoms, general knee pain and “other”. These indications were correlated with the K-L grade and result of the MRI.Overall, 40% of patients with a K-L grade of 0 had a meniscal tear compared to 89% of patients with a K-L score of 3, and 88% with a K-L score of 4. The indications for an MRI were grouped into meniscal symptoms (49), general pain (6) and other (5). In the group investigated for meniscal symptoms, the incidence of meniscal tears was 92% and 100% with a K-L grade of 3 and 4 respectively. This equated to a positive predictive value of 93% for K-L grade 3 and above, and 100% for K-L grade 4 alone.Given the predictability of the MRI findings in patients with significant osteoarthritis as well as meniscal symptoms, we conclude that this is an unnecessary investigation when used for this indication.     

Cystic nephroma (multilocular cyst) and mixed epithelial and stromal tumor of the kidney: a spectrum of the same entity?

The recently described mixed epithelial and stromal tumor (MEST) of the kidney and adult cystic nephroma (CN) (multilocular cyst) are rare benign cystic renal neoplasms that are composed of epithelial and stromal elements. Consensus criteria for distinguishing these entities have not been well established. Our objective in this study was to evaluate cases of CN and MEST to define the morphological, immunophenotypic, and clinical features of these two entities. Eleven cases from the files of a single institution diagnosed from 1996 to the present as either CN or MEST were reviewed. Architecturally, all lesions were composed of multiple noncommunicating cysts lined by a single layer of epithelial cells. All cases had areas with increased stromal cellularity and 8 cases had ovarian-like stroma present at least focally within the tumor. No stromal or epithelial cell atypia, blastemal elements, or increased mitotic activity was appreciated. The immunoprofile was also similar in the 7 cases stained and included epithelial reactivity with keratin and CAM 5.2 and stromal reactivity with estrogen receptor, progesterone receptor, smooth muscle actin, WT-1, vimentin, and focal desmin. All cases have acted in a benign fashion with no history of recurrence or metastasis. We propose that CN and MEST of the kidney represent a spectrum of the same entity. If the diagnosis of CN is limited to cases that are comprised entirely of thin fibrous-walled cysts, all 11 of our cases would be classified as MEST.     

The origin and distribution of CD68, CD163, and αSMA+ cells in the early phase after meniscal resection in a parabiotic rat model

We previously reported that circulating peripheral blood-borne cells (PBCs) contribute to early-phase meniscal reparative change. Because macrophages and myofibroblasts are important contributors of tissue regeneration, we examined their origin and distribution in the reparative meniscus. Reparative menisci were evaluated at 1, 2, and 4 weeks post-meniscectomy by immunohistochemistry to locate monocytes and macrophages (stained positive for CD68 and CD163), and myofibroblasts (stained positive for αSMA). Of the total number of cells, 13% were CD68⁺ at 1 week post-meniscectomy, which decreased to 1% by 4 weeks post-meniscectomy; of these, almost half of CD68⁺ cells (49.4%: 98.8% as PBCs) were green fluorescent protein (GFP)-positive post-meniscectomy (1, 2, and 4 weeks), indicating that the majority of CD68⁺ cells were derived from PBCs. Of the total cells, 6% were CD163⁺ at 1 week post-meniscectomy, which decreased to 1% by week 4. Of the CD163⁺ cells, the majority were GFP-positive (42.5%: 85.0% as PBCs) after 1 week; however, this decreased significantly over time, which indicates that the majority of CD163⁺ cells are derived from PBCs during the early phase of meniscal reparative change, but are derived from resident cells at later time points. Of the total cells, 38% were αSMA⁺ at 1 week post-meniscectomy, which decreased to 3% by 4 weeks. The proportion of GFP-positive αSMA⁺ cells was 2.8% after 1 week, with no significant change over time, which indicates that the majority of αSMA⁺ cells originated from resident cells. Here, we describe the origin and distribution of macrophages and myofibroblasts during meniscal reparative change.     

Immunization with excreted–secreted antigens reduces tissue cyst formation in pigs

It has been demonstrated that tachyzoite-pooled excreted–secreted antigens (ESAs) of Toxoplasma gondii are highly immunogenic and can be used in vaccine development. However, most of the information regarding protective immunity induced by immunization with ESAs is derived from studies using mouse model systems. These results cannot be extrapolated to pigs due to important differences in the susceptibility and immune response mechanisms between pigs and mice. We show that the immunization of pigs with ESAs emulsified in Freund's adjuvant induced not only a humoral immune response but also a cellular response. The cellular immune response was associated with the production of IFN-γ and IL-4. The humoral immune response was mainly directed against the antigens with molecular masses between 34 and 116 kDa. After intraperitoneal challenge with 10⁷ T. gondii of the Gansu Jingtai strain (GJS) of tachyzoites, the immunized pigs remained clinically normal except for a brief low-grade fever (≤40.5 °C), while the control pigs developed clinical signs of toxoplasmosis (cough, anorexia, prostration, and high fever). At necropsy, visible lesions were found at multiple locations (enlarged mesenteric lymph nodes, an enlarged spleen with focal necrosis, and enlarged lungs with miliary or focal necrosis and off-white lesions) in all of the control pigs but not in the pigs that had been immunized. We also found that immunization with ESAs reduced tissue cyst formation in the muscle (P?<?0.01). Our data demonstrate that immunization with ESAs can trigger a strong immune response against T. gondii infection in pigs.