PMC5223000_01
Intraoral examination shows relatively well defined elastic hard mass with ulcer in the left floor of the mouth, which measures approximately 36 x 33 mm.
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I to level II. Intraoral examination shows relatively well defined elastic hard mass with necrotic ulcer in the right to left floor of the mouth, which measures approximately 36 x 33 mm (Figure 1).
T2 weighted MRI sequence shows a 29 x 23 x 22 mm heterogeneous high signal mass in the floor of mouth.
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T2 weighted MRI showed a sequence that shows a 29 x 23 x 22 mm heterogeneous high signal mass in the floor of mouth (Figure 2).
Bilateral multiple neck lymph node metastases are shown. The level Ia LNs are swollen in 16 mm and 7 mm, right level Ib LNs are swollen in 23 mm and 13 mm, left level Ib LN is swollen in 5 mm, and left level IIa LN is swollen in 37 mm.
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The level Ia LNs are swollen in 16 mm and 7 mm, right level Ib LNs are swollen in 23 mm and 13 mm, left level Ib LN is swollen in 5 mm, and left level IIa LN is swollen in 37 mm (Figure 3).
(a) The histopathology of biopsy specimen (HE x40). The square of straight line was comprised of SCC, and dotted line was comprised of AC. Microscopically, the tumor consists of two components of SCC and AC. (b) The component of SCC. Nonkeratic dysplastic squamous cells proliferated with apoptosis and mitosis. (c) The component of AC. The cells change in a larger way and have high N/C rate and chromatin, a lot of mitosis and karyolysises are seen. A punctate necrosis is observed in the tumor nest, and the rosette structures are observed.
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The NET component was classified as AC (Figures 4(a)-4(c)).
(a) Immunohistochemical staining shows that the tumor cells are positive for synaptophysin and CD56 in SCC. (b) Immunohistochemical staining shows that the tumor cells are positive for HMW-CK/34B and P63 in SCC.
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There was no transitional part between SCC and AC (Figures 5(a) and 5(b)).
Intraoral examination 6 months after chemoradiotherapy shows small ulcer in the left floor of the mouth.
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The recurrence of the primary site occurred 6 months from the end of chemoradiotherapy with a diagnosis of primary site biopsy (Figure 6).
The histopathology of recurred resected specimen (HE x40, x100). Microscopically, the resected tumor of floor of mouth was SCC.
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The pathological diagnosis was SCC without AC in the primary site (Figure 7).
Lung metastasis and mediastinum lymph node metastases are depicted in the PET-CT.
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Although the primary and neck tumor did not recur, the multiple lung metastases and mediastinum lymph node metastases were diagnosed with FDG PET at 6 months after surgery (Figure 8).