Oral Squamous Cell Carcinoma Metastases to the Kidneys: Is It Common?

Metastases to the kidneys are rare and are frequently erroneously diagnosed as primary renal tumour. The kidney is unusual site of metastatic disease and is the fifth most common site of metastases in the body after lung, liver, bone and adrenals.

A 42-year-old male known case of operated buccal carcinoma of cheek (squamous cell carcinoma) presented with complaints of upper abdominal discomfort. Patient was investigated with Computed Tomography (CT) scan outside for the same and was detected to have multiple space occupying lesions in lungs, liver and both kidneys [Table/Fig-1a-c]. For characterization of these lesions patient was referred to us. In our institute patient underwent contrast-enhanced Magnetic Resonance Imaging (CE-MRI). On T2-weighted and CE-MRI images, multiple lesions were detected in liver, bilateral kidneys and left adrenal. Lesions in kidneys were multicentric, appeared as ‘black holes’ on MRI and showed restriction on Diffusion-weighted images [Table/Fig-2,3]. The imaging was classical in keeping with metastases involving the liver, kidney and left adrenal gland.

[Table/Fig-1a-c]:

(a) Axial contrast-enhanced CT scan of neck showing fat graft (arrow) in a case of operated squamous cell carcinoma buccal mucosa (b) Lung window sections showing cavitating and solid lung metastases (arrows) (c) Coronal contrast-enhanced MRI image showing multiple liver metastases (arrows)

[Table/Fig-2a,b]:

(a) Coronal MR-FIESTA sequence showing hypointense black hole lesions (arrows) in bilateral kidneys (b) Coronal contrast-enhanced MRI image hypo enhancing black hole lesions (arrows) better

[Table/Fig-3a-f]:

(a-c) Axial MR diffusion-weighted images showing bright lesions (arrows) in liver, left adrenal and bilateral kidneys (d-f) corresponding ADC maps MR image showing lesions appearing dark (arrows) suggestive of diffusion restriction

Metastases to the kidneys are rare and are frequently erroneously diagnosed as primary renal tumour. The kidney is unusual site of metastatic disease and is the fifth most common site of metastases in the body after lung, liver, bone and adrenals. The reported incidence of renal metastasis of extrarenal neoplasms varies from 2 to 20% [1,2]. Differentiation between primary renal malignant tumour and multifocal renal metastases is arduous when there is isolated renal involvement in a case of occult primary [3].

Since the classical symptoms of pain and haematuria is seen only in 20% of cases, metastatic renal disease is seldom clinically identified [2,4]. Most common tumours metastasizing to kidneys are lymphoma and lung carcinoma. Histopathologically, tumours metastasizing to kidneys are mostly adenocarcinomas, followed by squamous cell carcinomas, sarcomas, gem cell tumours and melanoma. Radiological imaging methods either CT scan or CEMRI is the most accurate method to screen for secondary renal tumours.

Renal metastases in patients with history of malignancy may mimic primary renal tumours. Radiologically, metastases are usually small, subcapsular in location, multicentric, bilateral, has a history of known primary and metastases to other organs at the time of presentation. Differentials include multicentric renal cell carcinoma, transitional cell carcinoma, pyelonephritis, or phlegmon [5].

Cai et al., have reported isolated renal metastasis from squamous cell lung cancer in a 53-year-old female [6]. Aksu et al., have also reported isolated renal metastasis from left colon cancer [7]. Giashuddin et al., in their case series of 11 cases with metastases to the kidneys identified seven cases from lung primary, three cases from lymphoma and one case from haemangiopericytoma [8]. Similarly, there are other few case reports described by various authors pertaining to this entity [9,10].

[1]. Choyke PL, White EM, Zeman RK, Renal metastases: clinicopathologic and radiologic correlation Radiology 1987 162:359-63.  [Google Scholar]

[2]. Mitnick JS, Bosniak MA, Rothberg M, Metastatic neoplasm to the kidney studied by computed tomography and sonography J Comput Assist Tomogr 1985 9:43-49.  [Google Scholar]

[3]. Uzal MC, Koçak Z, Uygun K, Altaner S, Gözen S, Ünlü E, A case of isolated bilateral renal metastases from carcinoma of the lung Turkish journal of Cancer 2004 34:81-84.  [Google Scholar]

[4]. Honda H, Coffman CE, Berbaum KS, CT analysis of metastatic neoplasms of the kidney Acta Radiol 1992 33:39-44.  [Google Scholar]

[5]. Graham TE, Rockey KE, Renal masses in adults Postgrad Med 1990 87:111-6.:121-26.  [Google Scholar]

[6]. Cai J, Liang G, Cai Z, Yang T, Li S, Yang J, Isolated renal metastasis from squamous cell lung cancer Multidiscip Respir Med 2013 8(1):2  [Google Scholar]

[7]. Aksu G, Fayda M, Sakar B, Kapran Y, Colon cancer with isolated metastasis to the kidney at the time of initial diagnosis Int J Gastrointest Cancer 2003 34:73-77.  [Google Scholar]

[8]. Giashuddin S, Cangiarella J, Elgert P, Levine PH, Metastases to the kidney: eleven cases diagnosed by aspiration biopsy with histological correlation Diagn Cytopathol 2005 32:325-29.  [Google Scholar]

[9]. Murphy WM, Zambroni BR, Emerson LD, Moinuddin S, Lee LH, Aspiration biopsy of the kidney simultaneous collection of cytologic and histologic specimens Cancer 1985 56:200-05.  [Google Scholar]

[10]. Gattuso P, Ramzy I, Truong LD, Utilization of fine-needle aspiration in the diagnosis of metastatic tumours to the kidney Diagn Cytopathol 1999 21:35-38.  [Google Scholar]