Immature Teratoma with Growing Teratoma Syndrome and Gliomatosis Peritonei Coexistence.

Ovarian germ cell tumours constitute 5% of all ovarian cancers. During the natural course and treatment of these tumours , there may be more unusual cases. One of them is gliomatosis peritonei, which is characterised by the spread of glial cells on the peritoneal surfaces, while the other one is growing teratoma syndrome characterised by the rapid growth of benign component and loss or shrinkage of the malignant component in response to systemic chemotherapy during the treatment of germ cell tumours. Herein, we present a case of coexistence of gliomatosis peritonei and growing teratoma syndrome during the treatment of a 29-year female with immature ovarian teratoma. Key Words: Germ cell tumours , Growing teratoma syndrome, Gliomatosis peritonei, Ovaries.

The importance of histological patterns on PD-L1 staining heterogeneity: Should we use pattern-based approach for selecting tumor samples for PD-L1 testing in lung adenocarcinomas?

Background/aim: Programmed death ligand-1 (PD-L1) is a predictive marker for immunotherapeutic agents. However, heterogeneous staining of PD-L1 can cause false-negative results. The aim of this study is to evaluate the importance of histological patterns on PD-L1 staining heterogeneity in lung adenocarcinomas (LAC). Materials and methods: PD-L1 immunohistochemistry (IHC) stain was performed to two different tissue cores of 128 LAC cases, and cut-off values are given for grouping the cases according to the percentage of staining (1%-10%, 11%-49%, 50%-100%). Staining rates between cores were compared and analyzed by their histological patterns. Also, the relation of the PD-L1 expression with the clinicopathological characteristics of the cases was analyzed. Results: Overall, PD-L1 expression was observed in 53 of 128 cases (41.4%, 1% cut-off), 23.5% of them were positive at 10% cut-off and 14.1% at 50% cut-off. PD-L1 expression was significantly related to the high grade micropapillary and solid patterns of adenocarcinomas (p:0.01). Staining cut-offs were mostly similar between cores (43/50, 86%) (k:0.843). However, 14% of them were positive only in one core (7 of 50). This false negativity was mostly related to the histological patterns. Conclusion: Our data reveal the heterogeneous staining of PD-L1 expression, also micropapillary and solid patterns show higher rates of PDL expression. Therewithal, these findings also highlight the importance of taking into consideration of histological patterns, when choosing a paraffin block for the PDL1.

Primary Retroperitoneal Müllerian Adenocarcinoma: Report of Two Cases Treated With Radical Surgery.

BACKGROUND: Primary retroperitoneal Müllerian adenocarcinoma (PRMA) is a very rare type of primary retroperitoneal tumour. CASE 1: A 45-year-old woman presented with left lower extremity swelling and pain. Imaging revealed that the tumour had invaded the left common iliac vein and artery, internal and external iliac arteries, sciatic and obturator nerves, and pelvic wall. CASE 2: A 37-year-old was admitted with pelvic pain. Imaging showed the tumor at the left iliac bifurcation infiltrating the internal iliac artery and left sciatic, obturator, and femoral nerves. Both of these patients were treated with radical surgery that achieved no visible tumour at the end of the operation. CONCLUSION: There is no guideline for the diagnosis and management of this entity due to its rarity. These cases should be managed at highly specialized centres with expertise in radical surgery.