Iatrogenic papillary renal cell carcinoma rupture with abdominal seeding three months after surgery

56 year-old man with unmotivated weight loss, night sweats and appetite loss, is referred to a chest-abdomen-pelvis CT which shows a 7x8x8 cm tumor with central necrosis in the right kidney (Figs. 1-2). The patient undergoes radical open nephrectomy during which the tumor ruptures. The histopathological report indicates papillary RCC type 2 (T2aN1M0).

Three months later, the patient presents with painful mass feeling in the scar.

Chest-abdomen-pelvis CT with with i.v. contrast in portovenous phase shows sequelae after right-sided nephrectomy with new focal retroperitoneal lesions suggestive of local recurrence and seeding, primarily along the liver, and implantation in the abdominal wall on the right side (Figs. 3-6).

Background

Renal cell carcinoma (RCC) is the most common solid lesion of the kidney and often detected incidentally as symptoms tend to manifest in late stages. RCC has many histological subtypes, the three most important being clear cell RCC (80–90%), papillary RCC (types I and II; 10–15%, of which 60–70% are type I), and chromophobe RCC (4–5%). For localised RCC, surgery is the only curative treatment with high-quality evidence [1].

RCCs usually metastasize following hematogenous and lymphatic pathways, but direct inoculation of neoplastic cells can happen during both surgery and biopsying, potentially leading to recurrence. Approximately 1% develop post-surgical abdominal seeding Klik eller tryk her for at skrive tekst. and 80% of seeding has been reported to occur after surgery [2]. The most likely mechanism of seeding is implantation of exfoliated cells from the tumour where resected tissue has passed during a procedure, such as biopsy, laparoscopy or surgery. The tumour cells exploit the physiological response to tissue trauma after surgery or injury, which may create beneficial microenvironment for implantation and growth of malignant cells [3].

Some papillary RCC tumours exhibit extensive central necrosis and are particularly prone to rupturing [4], potentially resulting in seeding. Only few cases are reported but one study found three common characteristics in patients with RCC developing seeding: intralesional central low attenuation, attachments with pararenal fascia and ill-defined margin [2].

Outcome and take-home message

As many patients with renal masses remain asymptomatic until the late stages of the disease, more than 50% of RCCs are detected incidentally when abdominal ultrasound (US), computed tomography (CT) or magnetic resonance imaging (MRI) is carried out for other medical reasons.

In case of prior radiological evidence of central necrosis in renal tumours, the radiologist can play an important role in multidisciplinary settings by drawing attention to the propensity of these tumours to rupture.