Introduction Spontaneous tumor regression is a rare phenomenon in medicine. It is defined as the
complete or partial disappearance of a malignant tumor without treatment or with treatment
for which there is as yet no evidence of efficacy (Everson & Cole, 1956).
Case Report A patient with clinically locally advanced oral cavity carcinoma of the ventral tongue
and floor of the mouth had squamous cell carcinoma confirmed histologically. Staging
revealed a clinical TNM stage of cT4a cN2b cM0. At the time of biopsy, superinfection
of the tumor was present. In addition, local peritonitis was evident after PEG placement.
The elevated laboratory parameters of infection regressed under i.v. antibiotics.
After case discussion in the tumor board and consultation with the patient, subtotal
glossectomy with segmental mandibulectomy, MRND on the right and SND level I-IV on
the left, tracheostomy, and defect coverage by chimeric scapular graft from the right
side were performed 4 weeks after histologic confirmation. Intraoperatively, the tumor
was already clinically clearly regressed with nevertheless deeply indurated tongue.
Histopathological examination of the resected tissue did not reveal any vital tumor
cells. Only a scarring and inflammatory-reactive process was described. The lymph
nodes were tumor-free (pN0 (0/83)).
Discussion The mechanisms of spontaneous tumor regression are not yet known. Possible factors
discussed include immunoreactive processes. In the case described by us, both the
inital proven infection and the significant improvement of general and nutritional
condition due to PEG insertion might have played a role in the spontaneous regression
of the tumor.
