Immunohistochemistry:
Undifferentiated tumor cells showed the following immunohistochemistry: CK: Positive (Figure1 B), P40: Negative, SALL 4(Figure-1 D): Negative, Synaptophysin: Negative (Figure-1 C), Vimentin: Negative, Desmin: Negative, CD20: Negative.
Squamous differentiated tumor area showed the following immunohistochemistry: CK (Cytokeratin): Positive (Figure 1-B), P40 (marker to distinguish squamous cell carcinoma from adenocarcinoma): Positive (Figure-3), SALL4 (transcription factor associated with embryonic cell pluripotency): Negative, Synaptophysin: Negative. The Ki67 (a marker of cell proliferation) index was 45-50%.
After the cumulative information from clinical, radiological, histomorphological, and immunohistochemical studies, the diagnosis of Undifferentiated carcinoma and squamous cell carcinoma arising in the background of MCTO was made. The patient was discharged without any postoperative complications. The patient is under adjuvant chemotherapy with Paclitaxel and carboplatin three weekly [Treatment line(L1), Cycle(Cl) completed]. She is tolerating the chemotherapy well and is stable without any complaints at two months of follow-up.