Is poorly differentiated squamous cell carcinoma something that can be cured?

Yes. Squamous cell Ca is a malignancy of tissues arising cutaneously (skin) and abutting internal structures such as bronchus and vagina/ cervix. High grade malignancies arising from such structures such as Ca of skin, bronchogenic Ca and cervix cancer can be cured iif not in metastatic phase, by wide resection,, followed by RT - chemo when needed.