Cancer during pregnancy has an incidence of 1/1,000, and when diagnosed, the most common ones are breast cancer (1/10,000), Hodgkin’s lymphoma (1/6,000), and head and neck cancer (1/10,000). If a diagnosis is made during pregnancy, the treatment cannot wait until delivery, and there is concern about the effects that radiotherapy may have on the foetus. The multidisciplinary group has to assess and ethically make decisions with regard to the mother and foetus.
A 35-year-old female, a carrier of Behcet’s disease, underwent 5 years of treatment with hydroxychloroquine, prednisone and low-molecular-weight heparin (the patient being a carrier of Behcet’s disease, there is a high risk for cancer of the oral cavity and oropharynx with an HR of 2·11, so the cancer could be related to the tonsil). The patient’s oncological situation started on December 2017 with a volume increase in preauricular, parotid and right mandibular angle, with a progressive growth. At this time, the foetus was of 17·5 weeks of gestation. An oral cavity tumour that invaded the right retromolar triangle was observed, and upon biopsy, a basaloid squamous cell carcinoma was diagnosed.
Radiotherapy treatment was started at 22 weeks of gestation; intensity-modulated radiation therapy (IMRT) was planned with a dose of 69·96 Gy to the primary tumour and 59·4 Gy to ganglion levels II, III and IV, bilaterally in 33 fractions. At fraction 27 a significant decrease in tumour volume was noted, so adaptive radiotherapy was performed to complete the treatment. Currently the patient has no clinical evidence of tumour pathology.
The risk of radiation exposure in pregnant women (after 20 weeks of gestation), being treated for cancers of the tonsil, reaching the foetus is minimal, with a reduced risk of a few or no effects.
Radiotherapy in tonsil cancer has been shown to be effective in combination with chemotherapy for local control of the disease. In the case of this pregnant patient, radiotherapy, as the only modality, provided local control and little exposure of radiation to the foetus.