Persistent dry cough: an unusual presentation of renal cell carcinoma

Abstract

A 68-year-old woman presented with a 3month history of persistent, gradually worsening dry cough, which, on occasion, woke her from sleep. She had no history of hemoptysis, recent respiratory tract infection, postnasal drip, asthma, seasonal allergies, travel or constitutional symptoms. She had quit smoking 10 years earlier. Her medical history included gastroesophageal reflux disease and benign adenomas of the colon. Her current medications included rabeprazole, atorvastatin and trazodone. The results of extensive investigations, including chest radiography, spirometry, flexible nasoendoscopy and a battery of blood tests, were negative, except for microcytic anemia, which we attributed to iron deficiency (hemoglobin 107 [normal 123-157] g/L).Six months following the initial presentation, our patient returned with worsening cough and complaints of drenching night sweats and unexplained weight loss of 5 lbs. A contrastenhanced computed tomography (CT) scan of the thorax showed prominent varicosities on the right side of the retroperitoneum. A subsequent CT of her abdomen and pelvis showed a hypervascular mass in the upper pole of the right kidney ( Figure 1), with no evidence of retroperitoneal lymphadenopathy.Our patient underwent open right radical nephrectomy for renal cell carcinoma (Führman grade 3, clear cell, with negative margins); there was no evidence of hepatic invasion. Following the surgery, the patient's cough completely resolved and did not recur during the next 2 years of follow-up.This patient's case represents a rare cause of chronic cough and an unusual presentation of renal cell carcinoma. Renal cell carcinomas secrete prostaglandins (mainly prosta glan din E 2 ), which have been implicated in enhancing the cough reflex via the EP 3 receptor pathway. 1,2 In our patient's case, a mass effect by the tumour on the posterior diaphragm may have also contributed to irritation and reflex cough. 3 References 1. Ishiura Y, Fujimura M, Nobata K, et al. Prostaglandin I 2 enhances cough reflex sensitivity to capsaicin in the asthmatic airway.Figure 1: Computed tomograph showing a large hypervascular right renal mass associated with the upper pole (arrow) in a 68-year-old woman with cough. There are multiple tumour lobulations that indent the hepatic capsule.Clinical images are chosen because they are particularly intriguing, classic or dramatic. Submissions of clear, appropriately labelled high-resolution images must be accompanied by a figure caption and the patient's written consent for publication. A brief explanation (250 words maximum) of the educational significance of the images with minimal references is required.

Persistent cough as a paraneoplastic presenting symptom in six patients with renal cell carcinoma

“…Paraneoplastic syndromes associated with RCC can range widely in their presentation. The six cases described above represent unusual instances of RCC, with only three similar cases of patients presenting with a chronic cough having been previously reported in the literature [3] , [4] , [5] . In all six cases, evaluation of the cough led to the diagnosis of a renal mass.…”

“…It is estimated that 10%–40% of patients develop paraneoplastic syndromes, including metabolic, hepatic, and hematologic syndromes [2] . Although the lungs are a common site of metastasis in patients with RCC, respiratory paraneoplastic syndromes are rare, with only three cases of RCC presenting with cough having been reported in the literature [3] , [4] , [5] . No clear explanation for these coughs has been elucidated; however, mass effect causing diaphragmatic irritation as well as paraneoplastic cytokines or growth factors have been hypothesized as possible causes.…”

Paraneoplastic Cough and Renal Cell Carcinoma

“…Also fortuitously the patient's presentation to our emergency room coincided with the publication the same week of a very similar case in the Canadian Medical Association Journal [ 1 ].…”

“…I have found reports of 11 patients (5 men, 6 women; age 24–68 years) with RCC whose cough appeared to be paraneoplastic rather than metastatic [ 1 , 5 , 8 – 14 ]. The oldest was published in Spanish in 1943 and aptly titled, Tos Renal, su importancia clinica , “Renal Cough, Its Clinical Importance” [ 8 ].…”

Protocol for a mixed-method study to assess chronic cough in patients with renal cell carcinoma: the prevalence, impact on quality of life, trigger and potential clinical application of chronic cough as an early screening tool in patients with kidney cancer

“…However, multiple patients report on patient forums within the Kidney Cancer UK website6 that they had an unexplained cough for many months before a diagnosis of RCC was made. Prior studies suggest that this cough occurs because of diaphragmatic irritation, pulmonary metastases or most likely a paraneoplastic syndrome 7–14. Many have reported that the cough resolves when the tumour has been treated either surgically or non-surgically (radiotherapy, embolisation or immunotherapy), but that the cough returns on recurrence of the primary tumour.…”