A 52-year-old man was referred to our hospital because of a growing left renal tumor. A contrast-enhanced CT scan revealed the presence of a 93-mm tumor in the upper pole of the left kidney (Fig. a,b) with tumor thrombus observed in the left renal vein (Fig. c). The tumor was gradually enhanced from the corticomedullary phase to the excretory phase. Enlarged lymph nodes were present at the left external iliac lesion; they were extra-regional lymph nodes and no other distant metastasis was observed (Fig. d). We diagnosed him as having left RCC classified as cT3aN0M1.\nOpen radical nephrectomy and dissection of left-sided pelvic lymph nodes were performed. The tumor and lymph nodes were examined macroscopically and microscopically. Macroscopically, a 80 × 80-mm, gray–whitish and solid tumor with necrotic tissue was located in the upper pole of the resected left kidney. Microscopically, the tumor consisted of a tubular and partly papillary structure (Fig. a). The neoplastic cells were cuboidal with eosinophilic cytoplasm. The Fuhrman nuclear grading system is used to describe the RMTSCC., This case was classified as Fuhrman nuclear grade 3 (Fig. b). The tumor was invaded into left renal vein, and metastatic lymph nodes were found at the left external iliac area (Fig. c). Fascicular growth with spindle cells and mucin stained by Alcian blue stain were found (Fig. a). Immunohistochemical findings showed the neoplastic cells to be diffusely positive for AMACR (Fig. b) and CK 7 (Fig. c). CD 10 was negative in the neoplastic cells (Fig. d). Although Ki-67 and p53 were negative in the neoplastic cells with low nuclear grade, they were positive in the neoplastic cells with high nuclear grade (Fig. e,f). We subsequently diagnosed him as having left RMTSCC classified as pT3aN0M1.\nThree months after nephrectomy, a PET-CT scan showed metastasis at the second lumbar vertebra with a maximum standard uptake value of 5.7 (data not shown). Six months after nephrectomy, vertebrectomy was performed for metastasis at the second lumbar vertebra. The pathological findings showed metastasis of the RMTSCC to the second lumbar vertebra. Nine months after nephrectomy, another PET-CT scan showed two 10-mm lymph nodes at the left internal iliac lesion with a maximum standard uptake value of 5.1 (data not shown). These were not regional lymph nodes of RCC, but he was not suffering from other causative diseases such as prostate or rectal cancer. Therefore, we diagnosed these lymph nodes as metastasis of RMTSCC. We are planning on administration of tyrosine kinase inhibitor.
In 2009, a 42-year-old non-smoking male presented to our hospital for the evaluation of a right lung nodule detected during physical examination. He underwent radical resection of the right lung, and the postoperative pathological report revealed a mucoid adenocarcinoma of the inferior lobe of the right lung (3.5 × 3.0 cm), but no positive lymph nodes (0 of 29; T2aN0M0 stage I). The patient relapsed in 2015. A computed tomography (CT) scan revealed a mass in the superior lobe of the right lung and mediastinal lymph node enlargement. He underwent resection of the residual right lung. Postoperative pathological evaluation and hematoxylin and eosin staining showed different histomorphologies in the primary lung site (mucinous type) (Fig a) and the fourth group of lymph node metastases (solid type, T2N2M0 stage III) (Fig b). Immunohistochemistry indicated a pulmonary origin of both tumors: TTF-1 and Napsin A were positive, and CK 5/6 and P63 were negative. We simultaneously detected ALK and EGFR gene status by reverse transcription-PCR (Amoy, Xiamen, China) in two tumor tissue specimens. The results indicated a positive EML4-ALK rearrangement in tissues and wild EGFR (Fig ). The patient received adjuvant chemotherapy and achieved stable disease.