Computed tomography and magnetic resonance imaging findings of metastatic rectal linitis plastica from prostate cancer: A case report and review of literature

Secondary rectal linitis plastica caused by prostatic adenocarcinoma - magnetic resonance imaging findings and dissemination pathways: A case report

BACKGROUND

Secondary rectal linitis plastica (RLP) from prostatic adenocarcinoma is a rare and poorly understood form of metastatic spread, characterized by a desmoplastic response and concentric rectal wall infiltration with mucosal preservation. This complicates endoscopic diagnosis and can mimic gastrointestinal malignancies. This case series underscores the critical role of magnetic resonance imaging (MRI) in identifying the distinct imaging features of RLP and highlights the importance of considering this condition in the differential diagnosis of patients with a history of prostate cancer.

CASE SUMMARY

Three patients with secondary RLP due to prostatic adenocarcinoma presented with varied clinical features. The first patient, a 76-year-old man with advanced prostate cancer, had rectal pain and incontinence. MRI showed diffuse prostatic invasion and significant rectal wall thickening with a characteristic "target sign" pattern. The second, a 57-year-old asymptomatic man with elevated prostate-specific antigen levels and a history of prostate cancer exhibited rectoprostatic angle involvement and rectal wall thickening on MRI, with positron emission tomography/computed tomography PSMA confirming the prostatic origin of the metastatic spread. The third patient, an 80-year-old post-radical prostatectomy, presented with refractory constipation. MRI revealed a neoplastic mass infiltrating the rectal wall. In all cases, MRI consistently showed stratified thickening, concentric signal changes, restricted diffusion, and contrast enhancement, which were essential for diagnosing secondary RLP. Biopsies confirmed the prostatic origin of the neoplastic involvement in the rectum.

CONCLUSION

Recognizing MRI findings of secondary RLP is essential for accurate diagnosis and management in prostate cancer patients.

68 Ga-PSMA-11 PET/CT and PET/MRI in Rectal Linitis Plastica Secondary to Prostate Adenocarcinoma

ABSTRACT

Primary or secondary rectal linitis plastica is rare. We describe MRI, 68 Ga-PSMA-11 PET/CT, and PET/MRI findings in a case of rectal linitis plastica secondary to prostate adenocarcinoma. In this case, the rectal linitis plastica was the first manifestation of the prostatic adenocarcinoma, and the rectum was the only metastatic site of the prostate adenocarcinoma. The rectal wall showed circumferential thickening with a concentric ring pattern on MRI, and diffuse intense 68 Ga-PSMA-11 uptake on PET/CT and PET/MRI. Familiarity with the imaging findings of rectal linitis plastica secondary to prostate adenocarcinoma may be helpful for recognition of this rare entity.

Linitis plastica of the rectum secondary to prostate carcinoma

Linitis plastica is an intramural carcinoma that may occur in any hollow organ. Rectal linitis plastica (RLP) is a morphological variant cancer that may occur as a primary form of cancer or secondary as a metastasis of a primary malignancy. We report the case of a man in his 70s with RLP secondary to prostate carcinoma who was initially suspected to have an obstructing rectal adenocarcinoma. During colonoscopy a segment of cobblestone mucosa was seen in the distal rectum. Subsequent imaging showed enhancement of all wall-layers of the rectum and diffuse retroperitoneal fat infiltration with traction on both ureters. A prostate-specific membrane antigen scan confirmed RLP secondary to a prostate carcinoma mimicking the clinical and radiological signs of an obstructing rectal carcinoma with retroperitoneal fibrosis.This case emphasises the possible pitfalls in the diagnosis of RLP and the importance of advanced imaging techniques, such as MRI, as well as appropriate histological samples. The patient underwent androgen deprivation therapy to which RLP responded well and neither systemic chemotherapy or surgery was necessary.

An unusual delayed rectal metastasis from prostate cancer masquerading as primary rectal cancer

Introduction and importance

Rectal metastasis of prostate cancer origin is exceedingly rare. Its clinical presentation, endoscopic morphology, and histopathology are similar to primary rectal cancer. Misdiagnosis may lead to inappropriate treatment.

Case presentation

We report a case of a gentleman in his 80's with a history of treated prostate cancer T3aN0M0 with radical prostatectomy sixteen years ago. He presented with one-year complaints of altered bowel habits and weight loss. Physical and rectal examination was unremarkable. Colonoscopy manifested some inflammatory changes in the rectum. The pelvis magnetic resonance imaging (MRI) showed an abnormal posterior rectal wall thickening 2 cm above the anal canal. Biopsy confirmed poorly differentiated adenocarcinoma of prostate origin. The staging workup was negative for other distant metastasis. After a multidisciplinary decision, the patient was started on androgen deprivation therapy and given palliative radiotherapy to the rectum. Six weeks later, the patient was stable with mild radiation proctitis.

Clinical discussion

Management of rectal metastasis varies depending on the patient's choice, the extent of metastatic burden, symptoms, age, life expectancy, quality of life and comorbidities. While surgery remains the standard of care, other option including radiotherapy, hormonal therapy and chemotherapy has been documented in the literature with survival of few weeks to 2 years.

Conclusion

Delayed rectal metastasis of prostate cancer after radical prostatectomy is a rare entity. Its clinical presentation and endoscopic and histopathological findings of rectal metastasis are similar to primary colorectal cancer, making diagnosis more demanding.

•

Rectum is a rare isolated site of metastasis from prostate cancer.

•

Symptoms and endoscopic morphology of rectal metastasis are similar to primary rectal cancer.

•

Prostate-specific antigen is not always raised in rectal metastasis.

•

Emergent lower gastrointestinal symptoms in patients with a history of prostate cancer warrants a multidisciplinary approach to reach an accurate diagnosis and prompt treatment.

•

Management of rectal metastasis depends on patient desire, the severity of symptoms, age, quality of life, life expectancy and comorbidities.

Linitis plastica of the rectum secondary to metastatic prostate cancer: A case report of a rare presentation and literature review

Linitis plastica is a rare tumor with poor prognosis. It is a circumferentially infiltrating intramural tumor which can result in rigid, nondistensible thickening of the affected organ. It most commonly affects the stomach, followed by the rectum, and can be due to primary or secondary cancer. Secondary rectal linitis plastica (RLP) caused by metastatic cancers has been reported from the stomach, breast, gallbladder, urinary bladder, and very rarely, the prostate, with only <5 reported cases in the literature. We report the case of a 66-year-old man who presented with altered bowel habit and loss of weight, with elevated prostate-specific antigen of 180.6 ng/mL. Sigmoidoscopy showed thickened rectal mucosa, and biopsy was negative for malignancy. Magnetic resonance imaging showed circumferential wall thickening, "target sign" appearance suggestive of RLP, PIRADS 5 lesion with extraprostatic extension, infiltrating bilateral seminal vesicles, and right neurovascular bundle. Repeat colonoscopy was performed under anesthesia, and deeper biopsy revealed poorly differentiated metastatic prostate adenocarcinoma. This case report highlights the atypical presentation of metastatic prostate cancer secondary to RLP, the rarity of this condition, and emphasizes the importance of deeper biopsy in RLP due to disease involvement predominantly in the submucosa and muscularis propria layers.

Metastasis to the rectum: A systematic review of the literature

BACKGROUND

Metastatic spread to the rectum is a rare finding, and management of rectal metastases (RM) is not standardized. The aim of the present study was to review the evidence on diagnosis, management and outcomes of RM.

METHODS

A computerized literature search through MEDLINE/PubMed, Embase and the Cochrane databases was performed, applying a combination of terms related to RM. Articles and abstracts were screened and final selection was done after cross-referencing and by use of predefined eligibility criteria.

RESULTS

Final analysis was based on 99 publications totaling 162 patients with RM from 16 different primary tumors. Most common origins of RM were breast (42 patients), stomach (38 patients), and prostate (16 patients). RM occurred metachronously in the majority of patients (77%). The main treatment was surgical resection (n = 32), followed by chemotherapy (n = 16). Median overall survival for breast RM, stomach RM, and prostate RM were 24 months (95% CI 9-39 months), 7 months (95% CI 0-14 months), and 24 months (95% CI 7-41 months), respectively.

CONCLUSION

RM is a rare and highly heterogeneous condition. Surgical treatment appears to be a valuable treatment option in selected patients, while overall prognosis depends mainly on the primary tumor.