Endocrine Abstracts

Introduction

The coexistence of pulmonary adenocarcinoma and papillary carcinoma of the thyroid is a rare event. The relationship between these two cancers is still unclear; Far from being a coincidence, it’s most often attributed to a genetic mutation (of which that of BRAF’s the most common). The management must focus on the most aggressive carcinoma. In this case, it’s pulmonary adenocarcinoma since the latter carcinoma is known for its indolent evolution and a better prognosis than the first.

Observation

A 45-year-old patient, with a family history of malignant thyroid neoplasia, underwent total thyroidectomy with central and lateral lymph node dissection for a thyroid nodule initially classified as Tirads 5. The histopathological examination was in favor of invasive papillary carcinoma of 3 cm, with the presence of vascular embolism, classified pt3bN1Mx. Radioiodine ablation therapy was performed. The postoperative evaluation objectives a dry cough that has been around for more than 3 months with a deterioration of the general condition; a chest X-ray supplemented by a CT scan revealed a pulmonary masse of 7 cm localized at the left lower lobe, scintigraphy was performed, and showed an absence of uptake by the pulmonary tumor. An echoguided biopsy of the mass showed pulmonary adenocarcinoma. Faced with the coexistence of these 2 primary tumors, we suspected a BRAF mutation that we confirmed its presence by the genetic study, and we completed the screening of other possible cancers. the CA 19 9 returned x5 the normal limit, the somatic examination found a naveus of 3 cm without malignancy signs. Our patient underwent a left lobectomy.

Discussion

BRAF represents one of the most frequently mutated protein kinase genes in human tumors. BRAF mutation can be observed in melanoma, papillary thyroid carcinoma, colorectal carcinoma, leukemia… In these cancers, various genetic aberrations of the BRAF proto-oncogene, such as different point mutations and chromosomal arrangements, have been reported. The most common mutation is BRAF V600E which can be detected by DNA sequencing and immunohistochemistry on fixed formalin, paraffin-embedded tumor tissue.

Conclusion

BRAF is one of the most frequently mutated protein kinases in cancer. Data to date support a role for BRAF as a driver of mutation that influences phenotype in different ways and indicates that it’s an important therapeutic target for patients with cancer.