Penile metastases from primary bronchus carcinoma – A case report and literature review

Abstract

Introduction: The penis is an uncommon site of secondary metastases, and in most cases the primary tumour is found in the bladder, prostate, rectum or sigmoid colon. It is an extremely rare secondary metastatic site of lung cancer, with only 28 cases found in a review of the current literature. The majority of these cases were squamous cell carcinoma, with only 3 cases of adenocarcinoma. Case presentation: Our case is a 55-year-old builder who presented with a painfully enlarged penis and loss of weight. He had a smoking history and was cachectic, with generalised lymphadenopathy and a firm mass on his left olecranon. His penis contained multiple firm nodules. Complete laboratory and imaging workup were done. Findings revealed a bronchial adenocarcinoma with multiple distant metastases, with the penile deposits as presenting symptoms. Management was with single high dose palliative half body irradiation. He survived 2 months after the presentation of penile metastasis. Conclusions: Cases of metastases to the penis are very rare and often carry a grave prognosis, as it is a late manifestation of malignant disease. The average survival from the diagnosis of penile metastases in our review was just under 4 months. It is however important to be aware and recognise this rare phenomenon, and differentiate it from primary penis cancer. Treatment of penile metastases is mostly palliative, but much can be done to improve the patient's quality of life. Early correct diagnosis may also alter the treatment of the primary tumour.

A Rare Case of Penile Metastases as a Harbinger of Primary Pulmonary Adenosquamous Carcinoma

“…Approximately one-third of penile metastases from lung cancer are detected at the same time as the primary tumor with the remainder detected in advanced disease at a mean interval of 18 months following primary tumor detection [ 3 , 11 ]. Penile metastases are rarely detected prior to the diagnosis of the primary lung cancer with only four cases with this presentation reported in the current literature, with our case being the fifth [ 2 , 3 , 6 , 7 ].…”

“…Clinical manifestations vary widely with the most common symptom being the presence of a palpable penile mass which has been reported in 45% to 80% of patients with an average size of 3.5 cm [ 3 , 5 , 6 , 10 ]. Low flow priapism secondary to occlusion of the venous plexus by tumor cells, the so-called “malignant priapism,” has been reported in 20% to 53% of patients with secondary penile metastases and may be a particularly useful clinical tool in differentiating secondary penile metastases from primary penile malignancies as it is almost never observed in the latter [ 6 , 10 , 12 ]. Although penile pain and obstructive uropathy are infrequently reported as initial symptoms, they may be present in advanced disease secondary to increased mass effect and infiltration, notably into the corpus spongiosum [ 10 ].…”

“…Although penile pain and obstructive uropathy are infrequently reported as initial symptoms, they may be present in advanced disease secondary to increased mass effect and infiltration, notably into the corpus spongiosum [ 10 ]. As patients presenting with penile metastases often have widespread metastatic disease, symptoms specific to the primary tumor are common, including dyspnea, cough, and weight loss in the setting of a primary lung malignancy [ 2 , 3 , 6 ].…”

“…The majority of the reported secondary penile metastases from lung cancer are of squamous cell carcinoma origin (23 of 40 cases) followed by adenocarcinoma origin (7 of 40 cases) [ 3 ]. In contrast, the incidence of pulmonary adenocarcinoma is greater than pulmonary squamous cell carcinoma with an incidence of 40% and 25–30% in the lung cancer population, and this discrepancy may be the result of a female-predominant incidence of pulmonary adenocarcinoma [ 6 , 14 ]. Penile metastasis from pulmonary adenosquamous carcinoma is even rarer, which up until now has only been reported once in the literature, with our case being the second [ 3 ].…”

“…Approximately one-third of penile metastases from lung cancer are detected at the time of primary tumor detection with the vast remainder detected several months later, often in end-stage disease [ 3 ]. Penile metastases are rarely detected prior to the diagnosis of a primary lung cancer with only four cases reported in the current literature [ 2 , 3 , 6 , 7 ]. We report a rare case of penile metastases as the presenting sign of a metastatic ASC of the lung.…”