Spontaneous regression of cutaneous head and neck melanoma: Implications for the immunologic control of neoplasia

Background. Spontaneous regression of cancer in the head and neck is a rare event. Moreover, there are rare reported cases of spontaneous regression of primary head and neck melanoma with accompanying immunohistochemical analysis of the tumor. Methods. We used detailed preoperative and postoperative pathologic examination of a lesion in the right supraclavicular region. Results. Pathologic examination of the initial specimen identified a melanoma of superficial spreading type with vertical growth and a thickness of 1.8 mm. The excised specimen demonstrated a complete regression of the melanoma with a florid host inflammatory response predominantly composed of a histiocytic reaction. Conclusion. The case presented illustrates histopathologic findings occurring in a head and neck melanoma as it is undergoing spontaneous regression. These findings point to a potentially critical role for histiocytes in effecting tumor elimination. Pathologic analysis of spontaneous head and neck melanoma regression will ultimately facilitate an improved understanding of naturally-occurring tumor elimination.