Fatal Pulmonary Tumour Thrombotic Microangiopathy (PTTM) Associated with Signet Ring Cell Carcinoma of Colon: An Autopsy Diagnosis

Case Report

Austin J Forensic Sci Criminol. 2017; 4(3): 1065.

Fatal Pulmonary Tumour Thrombotic Microangiopathy (PTTM) Associated with Signet Ring Cell Carcinoma of Colon: An Autopsy Diagnosis

Vishwakarma S, Arulselvi S*, Singh J# and Behra C#

Department of Forensic Medicine, AIIMS, India #Authors are equally contributed

*Corresponding author: Arulselvi Subramanian, Department of Lab Medicine, Jai Prakash Narayan Apex Trauma Centre, AIIMS, New Delhi 110029, India

Received: June 03, 2017; Accepted: June 23, 2017; Published: July 10, 2017

Abstract

Pulmonary tumor thrombotic microangiopathy (PTTM) is a rare clinicopathological entity in which the tumor cells embolize to the pulmonary vasculature leading to fibro cellular intimal thickening and arteriolar occlusion by cellular intimal proliferation. Sub-acute respiratory failure, pulmonary hypertension, right sided heart failure and sudden death may be seen due to consequences of stenosis of blood vessels.

We describe a case of a 23 year old man who presented with alleged history of found unconscious and declared brought death. He was clinically diagnosed as refectory sepsis with ventilator associated pneumonia with acute kidney injury. Past history revealed Crohn’s disease and treatment with Azathioprine and prednisolone. Mucicarmine was positive in colonic tumor as well as in pulmonary tumor cell emboli with recanalization and intimal fibro cellular proliferation of small arteries. A postmortem diagnosis of poorly differentiated signet ring cell carcinoma of colon with PTTM was made based on autopsy results.

Unfortunately, PTTM is difficult to diagnose and is mostly a post mortem diagnosis with an extremely poor prognosis. Pulmonary hypertension due to metastatic tumor emboli should be included in the differential diagnosis of various causes of dyspnea in patients with cancer.

Keywords: Pulmonary tumor thrombotic microangiopathy; Cell carcinoma

Introduction

Pulmonary tumor thrombotic microangiopathy (PTTM) is a rare clinicopathological entity in which the tumor cells embolize, organize and recanalize to the pulmonary vasculature leading to fibro cellular intimal thickening and vessel stenosis. Sub-acute respiratory failure, pulmonary hypertension, right sided heart failure and sudden death may be seen due to consequences of stenosis of blood vessels caused by PTTM. In this report, we describe a rare case of PTTM associated with metastatic colon carcinoma diagnosed on postmortem examination of a young man. We also aim to review the literature related to PTTM and associated malignancies and how they were diagnosed and managed.

Case Presentation

Clinical course

The deceased, a 23 year old man was brought with alleged h/o unconsciousness for an hour in a public place. On examination, patient was breathless and gasping. His BP was 110/60 mm Hg and pulse was feeble. He was immediately started on oxygen inhalation and nebulization and shifted to ICU. In ICU he was put on ventilator with i/v antibiotics and symptomatic care. On systemic examination respiratory system showed only gasping efforts and cardiovascular system showed feeble heart sounds. On CNS examination, Glasgow coma scale was E1V1M1. There was history of fever and breathlessness since past 3-4 days along with greenish expectoration. He was clinically diagnosed and treated as a case of refractory sepsis with septic shock, ventilator associated pneumonia and acute kidney injury.

Previous special investigations

His previous records revealed complaints of pain in abdomen and increased frequency of stool admixed with blood off and on, two years back. Colonoscopy revealed a long serpiginous ulcer present in transverse colon and impression of-colonic disease was made. Biopsy taken from recto sigmoid region was reported as scanty tissue with nonspecific acute on chronic inflammation. Contrast enhance CT was reported as diffuse colitis with rectal involvement with loss of haustrations and shortening of colon suggestive of ulcerative colitis. USG whole abdomen revealed slightly hypoechoic liver, mild fatty infiltration of pancreas, swollen tip of pancreas but no periappendiceal mass or fluid collection. Diffuse concentric thickening of colonic walls was seen. His routine blood investigations done twice during this period were within normal limits. Therefore he was considered as a case of inflammatory bowel disease (IBD) and since last two year she was on treatment with Azathioprine and prednisolone. He had poor compliance to medicines and was lost to follow up for last 8 months. During hospital stay his condition deteriorated further and on fifth day of admission, despite all our efforts the patient could not be revived and was declared dead.

On Autopsy

External examination: The deceased was averagely built and averagely nourished. Rigor mortis had set in and postmortem lividity present. Both corneas were hazy; pupils were dilated and fixed. On examining natural orifices- NAD (no abnormality detected).

Internal examination: Head & Neck: was normal, Scalp & Vault of Skull – Showed no gross abnormalities. Meninges - The dura appeared normal. There was no evidence of venous sinuses thrombosis. There was no subdural/subarachnoid hemorrhage. Brain weighed 1400 gms. There was no evidence of any hemorrhage externally or on cut surface of brain. There was no midline shift or herniation.

Thorax: Pleura and pleural cavity: The pleural cavities showed occasional flimsy adhesions with approximately 75-100 ml of straw colored fluid in both pleural cavities. Larynx, trachea and bronchi were within normal limits. Few small paratracheal lymph nodes were noted. Lungs - Right lung weighed 715 grams and left lung weighted 610 grams. Both lungs appeared boggy and subcrepitant. Pericardium & Pericardial cavity appeared unremarkable. Heart weighed 350 grams. The inflow/out flow tracts, valves and papillary muscles were normal. The right and left ventricular walls were normal. Coronary Arteries Both right and left coronaries were patent. No atheromatous lesions were seen. The great vessels were unremarkable.

Abdomen: Peritoneum and peritoneal cavity had 600 ml thin straw color peritoneal fluid multiple adhesions and palpable nodularity at places. Stomach – mucosa was diffusely hemorrhagic with flattened mucosal roughage. Serosal surface was grossly unremarkable. Large Intestine had focal red black colored ulcerated mucosa. External surface of small and large intestine was edematous and congested at places. Intestinal was focally thickened with polypoid areas causing narrowing of intestinal lumen in small intestine, large intestine and rectum (Figure 1). Rectal lumen was narrowed and thickened (1.5 cm) at places. Rectal mucosa was reddish black with presence of mucosal ulcer ranging from 0.5 cm to 2 cm. Liver, Gall Bladder and Bile Ducts - Liver weighed 1500 grams. The external surface was smooth. Cut surface was mildly congested. The Gallbladder and bile duct were normal. The hepatobiliary passage was patent. Pancreas was unremarkable. Kidneys - The left and right kidneys weighed 250 gms each. Capsule could be stripped off easily. The corticomedullary junction was well defined. Urinary Tract was within normal limits. Spleen – weighed 150 grams and cut surface appeared congested. Both adrenals appeared normal and their cut surfaces were unremarkable.