PMC8349051_01
Imaging findings at the time of initial diagnosis A, B) Chest computed tomography scan shows a primary lesion in the right upper lobe and a massive pericardial effusion. C, D) F18 fluorodeoxyglucose positron emission tomography scan shows uptake by the primary lesion, mediastinal lymph nodes, and pelvic bone.
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Multiple metastatic lung cancer (cT4N3M1c) was diagnosed by computed tomography and positron emission tomography (Fig. 1).
Computed tomography findings A) Progression of the primary lesion after 4 years of alectinib treatment. B) Partial response during cytotoxic chemotherapy for SCLC. C) Progression of the primary lesion after 2 years of cytotoxic chemotherapy for SCLC. D) Partial response after alectinib rechallenge.
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After 4 years of alectinib treatment, no metastases appeared, but the primary lesion progressed (Fig. 2A). TTF-1 (-), and ALK-1 (-), and the adenocarcinoma components were CD56 (-), synaptophysin (-), TTF-1 (+), and ALK-1 (+) (Fig. 3A). Two regimens of cytotoxic chemotherapy for SCLC (cisplatin plus irinotecan as the sixth-line treatment and amrubicin as the seventh-line treatment) showed a partial response (Fig. 2B), but serum tumor markers such as carcinoembryonic antigen (CEA) and sialyl-Lewis X-i antigen (SLX) increased gradually (Fig. 4). Imaging findings showed progression of the primary lesion and multiple brain metastases (Fig. 2C). ALK-1 (+), and disappearance of the SCLC component (Fig. 3B). Alectinib was re-administered, which resulted in a partial response and decreased CEA and SLX levels (Fig. 2, Fig. 4).
Pathological findings A) The second biopsy sample shows combined small cell carcinoma. SCLC components are positive for CD56 and synaptophysin, and adenocarcinoma components are positive for TTF-1 and ALK-1. B) The third biopsy sample shows only adenocarcinoma without SCLC components. Immunohistopathological analysis shows positive staining for TTF-1 and ALK-1, but negative staining for CD56 and synaptophysin.
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TTF-1 (-), and ALK-1 (-), and the adenocarcinoma components were CD56 (-), synaptophysin (-), TTF-1 (+), and ALK-1 (+) (Fig. 3A). Two regimens of cytotoxic chemotherapy for SCLC (cisplatin plus irinotecan as the sixth-line treatment and amrubicin as the seventh-line treatment) showed a partial response (Fig. 2B), but serum tumor markers such as carcinoembryonic antigen (CEA) and sialyl-Lewis X-i antigen (SLX) increased gradually (Fig. 4). ALK-1 (+), and disappearance of the SCLC component (Fig. 3B). Alectinib was re-administered, which resulted in a partial response and decreased CEA and SLX levels (Fig. 2, Fig. 4).