Brief Answer:
it's a tumor...

Detailed Answer:
Hello,

a neoplasm is a tumor, that is an abnormal growth of cells which may originate from any kind of cell in the body. Normally the cells have a limited lifetime which eventually stops after completing some cycles of reproduction. In neoplasms the cells loose the potential of programmed death and divide forever (or until they die due to lack of nutrients or due to other external factors), because of a mutation. Benign neoplasms are tumors without potential for invasion or metastasis. Malignant neoplasms (cancer) invade the surrounding tissue and may metastasize.

A mole is common example of a benign neoplasm. Lung cancer is a common type of a malignant neoplasm.

The penis (and actually no kind of tissue) cannot be excluded from the potential for neoplasm formation, that is a neoplasm may originate from the penis as well as any other tissue.

I hope you find my comments helpful!
You can contact me again, if you'd like any clarification or further information.

Kind Regards!

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