EMRCS PATHO 5 Flashcards by yamin bocha

A patient undergoes excision of a lump and the pathologist then examines a histological section and identifies a clump of Reed Sternberg cells. What is the most likely diagnosis?

	Thymoma
	Papillary carcinoma of the thyroid
	Hodgkins lymphoma
	Kaposi sarcoma
	Carcinoma of the parathyroid gland

Reed Sternberg cells are diagnostic of Hodgkins lymphoma

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Which statement relating to phaeochromocytoma is untrue?

They are tumours of chromaffin cells in the adrenal medulla.
They are bilateral in 10% of cases.
When located in an extra adrenal location have a higher incidence of malignancy.
May be associated with an elevated urinary VMA.
Up to 40% may have a blood pressure within the normal range.

Normotension is seen in around 10% cases. The remainder show a degree of hypertension.

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A 69 year old man presents with a purple lesion on his forearm. It is excised and an a 3 cm Merkel cell tumour is diagnosed. Which of the following statements relating to this diagnosis is false?

He should undergo a sentinel lymph node biopsy.
Lymphovascular invasion is typically seen histologically
They are more common in immunosupressed patients
Histologically they may resemble pyogenic granuloma
They are associated with visceral metastasis

Merkel cell tumours are rare cutaneous tumours. Histologically they consist of sheets and nodules of hyperchromatic epithelial cells, with high rates of mitosis and apoptosis. As such they are relatively easy to distinguish from pyogenic granuloma which has no features of malignancy and would not show lymphovascular invasion.

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A 58 year old lady undergoes a screening mammogram and appearances are suspicious for ductal carcinoma in situ. A stereotactic core biopsy is performed. If ductal carcinoma in situ is to be diagnosed, which of the following pathological features must not be present?

	Nuclear pleomorphism
	Coarse chromatin
	Abnormal mitoses
	Angiogenesis
	Dysplastic cells infiltrating the suspensory ligaments of the breast

Dysplastic cells infiltrating the suspensory ligaments of the breast

The presence of invasion is a hallmark of invasive disease and thus would not be a feature of DCIS. Angiogenesis may occur in association with high grade DCIS.

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Which of the following does not occur as a pathological response to extensive burns?

	Plasma leakage into interstitial space
	Absolute polycythaemia
	Increased haematocrit
	Keratinocyte migration during healing
	Cardiac output reduction by 50% in first 30 minutes

Haemolysis is the main pathological response.

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A 67 year old man is investigated for biliary colic and a 4.8 cm abdominal aortic aneurysm is identified. Which of the following statements relating to this condition is untrue?

The wall will be composed of dense fibrous tissue only
The majority are located inferior to the renal arteries
They occur most often in current or former smokers
He should initially be managed by a process of active surveillance
Aortoduodenal fistula is a recognised complication following repair.

They are true aneurysms and have all 3 layers of arterial wall.

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Which of the following statements in relation to the p53 tumour suppressor protein is false?

	It may induce necrosis of cells with non repairable DNA damage
	It is affected in Li Fraumeni syndrome
	It can induce DNA repair
	It can halt the cell cycle
	It may inhibit angiogenesis

When DNA cannot be repaired it will induce cellular apoptosis (not necrosis)

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Which of the following cell types is most likely to be identified in the wall of a fistula in ano?

	Squamous cells
	Goblet cells
	Columnar cells
	Ciliated columnar cells
	None of the above

A fistula is an abnormal connection between two epithelial lined surfaces, in the case of a fistula in ano it will be lined by squamous cells.

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A 22 year old man is referred to the surgical clinic. He has been complaining of varicose veins for many years. On examination he has extensive varicosities of the right leg, there are areas of marked port wine staining. The saphenofemoral junction is competent on doppler assessment. The most likely underlying diagnosis is:

	Deep vein thrombosis
	Klippel-Trenaunay syndrome
	Varicose veins due to sapheno-popliteal junction incompetence
	Sturge - Weber syndrome
	Angiosarcoma

Klippel-Trenaunay syndrome

Signs and symptoms
The birth defect is diagnosed by the presence of a combination of these symptoms:
One or more distinctive port-wine stains with sharp borders
Varicose veins
Hypertrophy of bony and soft tissues, that may lead to local gigantism or shrinking.
An improperly developed lymphatic system

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A 53 year old woman presents with a bloody nipple discharge. On mammography, there is calcification behind the nipple areolar complex. A core biopsy shows background benign change, but cells that show comedo necrosis which have not breached the basement membrane. Which of the lesions below is most likely?

	Fibrocystic disease of the breast
	Ductal carcinoma in situ
	Invasive ductal carcinoma
	Atypical ductal hyperplasia
	Lobular carcinoma in situ

Comedo necrosis is a feature of high nuclear grade ductal carcinoma in situ. It is has a high risk of being associated with foci of invasion.

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A 68 year old man presents with an ulcerated lesion on his right cheek. It is excised and on histological assessment a squamous cell carcinoma is diagnosed. It measures 25mm in diameter and is 4mm deep. Which of the following statements relating to this condition is false?

In this particular case margins of at least 6mm are required
Use of cryosurgery to treat this patients lesion would have been unsafe
Use of radiotherapy to treat this lesion would have been unsafe
This patients local recurrence rate may approach 15%
The disease usually spreads via lymphatics

This man has an SCC with significant risk of metastasis. Although cryotherapy may be used to treat SCC it would be most unsafe in this setting as the lesion extends deeply. However, radiotherapy is a safe treatment modality for SCC and may be used in selected cases. It is unwise to use radiotherapy in areas prone to radionecrosis e.g. the nose.

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A 23 year old man presents with weight loss fatigue and lymphadenopathy. He is diagnosed with tuberculosis. Which of the following processes most closely matches the underlying pathological process?

	Type 1 hypersensitivity reaction
	Type 2 hypersensitivity reaction
	Type 3 hypersensitivity reaction
	Type 4 hypersensitivity reaction
	None of the above

Granulomas (which occur in tuberculosis) are a feature of Type 4 hypersensitivity reactions

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A 73 year old man undergoes an emergency amputation for severe lower limb sepsis and gangrene. Post operatively he develops disseminated intravascular coagulation. Which of the following clotting factors will be most rapidly consumed in this process?

	Factor V and VIII
	Factor I
	Factor I and III
	Factor III and VII
	Factor VI and VIII

DIC Will tend to consume factors five and eight intially (and platelets).

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A pregnant women suddenly develops bilateral leg swelling. Her mother and aunt were troubled by the same problem. What is the most likely underlying abnormality?

	Anti endomysial antibodies
	Anti nuclear antibodies
	Anti cardiolipin antibodies
	Anti thyroid antibodies
	Anti mitochondrial antibodies

Anti phospholipid syndrome= following antibodies
Lupus anticoagulant
Anti-cardiolipin
Anti-β2-glycoprotein

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A 63 year old Japanese man presents with epigastric discomfort and iron deficiency anaemia. He undergoes an upper GI endoscopy, where the following appearances are found:
The most likely diagnosis is:

	Squamous cell carcinoma
	Linitis plastica
	Leiomyosarcoma
	Gastric varices
	None of the above

Linitis plastica produces a diffuse infiltrating lesion, the stomach is fibrotic and rigid and will not typically distend. This may be described as a ‘leather bottle stomach’. Diagnosis is made with a combination of pathology examination with endoscopy, radiological or surgical assessment. Pathologically signet-ring cell proliferation occurs.

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A 52 year old lady is referred to the breast clinic with symptoms of nipple discharge. The discharge is usually thick and green. Which of the following statements relating to the most likely underlying diagnosis is untrue?

The majority of patients will be smokers
Typically produces blood stained nipple discharge
It is not associated with increased risk of breast cancer
May result in development of mammary duct fistula
May require total duct excision (Hadfields operation) if it fails to resolve

Discharge of this type of material is most likely to be due to duct ectasia. Green or brown discharge is most common. Blood stained discharge should raise concern of intraductal papilloma or cancer.

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Which of the following statements relating to gas gangrene is untrue?

There is necrosis with putrefaction
The causative pathogens may be detected on normal perineal skin
Treatment with low dose penicillin is indicated
Hyperbaric oxygen may be beneficial
Clostridium perfringens is a recognised cause

Rapid surgery and high dose antibiotics are indicated in the treatment of gas gangrene.

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A 30 year old man presents with abdominal distension, a laparotomy is performed, at operation the abdomen is filled with a large amount of gelatinous fluid. What is the most likely underlying diagnosis?

	Infection with entamoeba histolytica
	Pseudomxyoma peritonei
	Metastatic colonic cancer
	Chylous ascites
	None of the above

Pseudomyxoma is associated with the deposition of large amounts of gelatinous material. The appendix is the commonest organ or origin.

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A 30 year old man is suspected of having appendicitis. At operation an inflamed Meckels diverticulum is found. Which of the following vessels is responsible for the blood supply to a Meckels diverticulum?

	Right colic artery
	Vitelline artery
	Appendicular artery
	Internal iliac artery
	External iliac artery

The vitelline arteries supply a Meckels these are usually derived from the ileal arcades.

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A 45 year woman presents with haematuria. She has a temperature of 38 oC and is found to have a Hb 17g/dl. Her urine dipstick shows nitrites and 3+ blood. Blood and urine cultures are negative. What is the most likely cause?

	Urinary tract infection
	Renal vein thrombosis
	Adult polycystic kidney disease
	Hypertensive nephropathy
	Membranous glomerulonephritis

Renal vein thrombosis is a common feature of renal cell carcinoma as it invades the renal vein. Other features include PUO, left varicocele and paraneoplastic endocrine effects due to erythropoietin factor, renin, ACTH and PTH like substance.

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A 5 year old boy is found to have a Meckels diverticulum at an appendicectomy and it looks to be non inflamed. What type of epithelium is most likely to be found in the diverticulum?

	Gastric mucosa
	Non stratified squamous epithelium
	Ileal mucosa
	Stratified squamous epithelium
	Jejunal mucosa

Most asymptomatic Meckels diverticulum will be lined by ileal mucosa. Those which present with bleeding are more likely to contain gastric type mucosa.

Which of the following associations are incorrect?

Afro-Caribbean skin and keloid scarring
Extensive third degree burns and wound contraction
Chemotherapy and dehisence of healed wounds
Poor healing at the site of previous radiotherapy
Zinc deficiency and delayed healing

Chemotherapy and dehisence of healed wounds

A 45 year old woman is identified as having a gastric gastro-intestinal stromal tumour. What is the usual cell of origin of these lesions?

	Brunners glands
	Interstitial cells of Cajal
	Primitive stem cells of the gut wall
	Fundic glands
	Antral goblet cells

GIST’s are derived from the interstitial pacemaker cells of Cajal. This means that they are often located extramucosally and macroscopically, demonstrate little mucosal disruption.

A 23 year old man fractures his right tibia in a sporting accident. At which point in the healing process is fracture callus first visible radiologically?

	1 day
	7 days
	8 weeks
	6 weeks
	3 weeks

Fracture callus is composed of fibroblasts and chondroblasts and the synthesis of fibrocartilage. It is typically visible on radiographs approximately 3 weeks following injury. If delayed then there may be risk of non union.

Of the options below, which does not cause lymphadenopathy? ``` Kawasaki disease Systemic Lupus Erthematosus Phenytoin Hydralazine Amiodarone ```

Amiodarone

A 23 year old man is reviewed on the ward 10 days following a laparotomy. The wound is inspected and is healing well. Which of the following processes is least likely to be occurring in the wound at this stage? ``` Angiogenesis Synthesis of collagen Necrosis of fibroblasts Secretion of matrix metalloproteinases by fibroblasts Proliferation of fibroblasts ```

Fibroblasts are an important cell type in healing wounds. They typically proliferate in the early phases of wound healing. They release matrix metalloproteinases and these facilitate in the remodelling of the matrix within the healing wound. Necrosis in a healing wound would be unusual as wounds will tend to show clinical evidence of angiognesis by this time.

A 25 year old women presents with a slowly enlarging mass on the side of the face. Clinical examination demonstrates that the mass is located in the tail of the parotid gland. There is no evidence of facial nerve involvement. What is the most likely cause? ``` Sialolithiasis Adenocarcinoma Warthins tumour Oncocytoma Pleomorphic adenoma ```

Pleomorphic adenomas are the commonest tumours of the parotid gland and are often slow growing, smooth and mobile. Warthins tumours are typically found in elderly males and are composed of multiple cysts and solid components consisting of lymphoid tissue. Warthins tumours are most often found in the tail of the parotid gland, but not in 25 year old females, where a pleomorphic adenoma remains the most likely lesion.

Beta-naphthalamine is associated with which of the following malignancies? ``` Lung cancer Bowel cancer Bladder cancer Liver cancer Renal cancer ```

Beta-naphthalamine is used in the rubber industry. The following factors are associated with the development of bladder cancer: smoking occupational: aniline dyes used in printing and textile industry, rubber manufacture schistosomiasis drugs: cyclophosphamide

A 48 year old lady is admitted with abdominal distension. On examination, she is cachectic and has ascites. Her CA19-9 returns highly elevated. What is the most likely cause? ``` Metastatic ovarian cancer Metastatic pancreatic cancer Metastatic gastric cancer Metastatic colonic cancer Pseudomyxoma peritoneii ```

Although not specific CA 19-9 in the context of this history is highly suggestive of pancreatic cancer over the other scenarios.

A 6 month old boy is brought to the clinic with difficulty breathing and weight loss. On examination, he is found to have a firm para testicular mass. What is the most likely diagnosis? ``` Teratoma Seminoma Adenocarcinoma Rhabdomyosarcoma Malignant fibrous histiocytoma ```

Rhabdomyosarcomas as one of the more common malignant solid tumours in children (though all are rare). They have an aggressive behavior pattern and metastases are common. Teratomas are nearly always benign in younger children. Seminomas are very rare indeed. Malignant fibrous histiocytomas are almost never found in this location.

A 56 year old man with Wilsons disease presents with right upper quadrant discomfort. An ultrasound scan is performed and this demonstrates a mass lesion in the right lobe of the liver. What is the most appropriate method of establishing the underlying diagnosis? ``` PET CT scan Ultrasound guided biopsy Measurement of serum alpha feto protein MRI scan of the liver CT scan of the liver ```

This is likely to be a hepatocellulcar carcinoma. Diagnosis is usually made by AFP measurement (with further imaging depending on the result). Biopsy should not be performed as it may seed the tumour. Chronic liver diseases such as Wilsons disease (Hepato-lenticular degeneration) increase the risk.

A 55 year old man has suffered from reflux oesophagitis for many years. During a recent endoscopy a biopsy is taken from the distal oesophagus. The histopathology report indicates that cells are identified with features of coarse chromatin and abnormal mitoses. The cells are confined to the superficial epithelial layer only. Which of the following accounts for this process? ``` Metaplasia Apoptosis Autoimmune oesophagitis Dysplasia Infection with Helicobacter pylori ```

Dysplasia tends to develop as a result of prolonged stimulation by precipitants. Removal of these precipitants may possibly reverse these changes. Replacement of differentiated cells with another cell type describes metaplasia rather than dysplasia. The absence of invasion distinguishes this from malignancy.

Which one of the following confers the least risk of developing osteoporosis? ``` Obesity Long term unfractionated heparin therapy Gastrectomy Osteogenesis imperfecta Diabetes ```

Obesity Low body weight is a risk factor for osteoporosis.

A 63 year old man has a history of claudication that has been present for many years. He is recently evaluated in the clinic and a duplex scan shows that he has an 85% stenosis of the superficial femoral artery. Two weeks later he presents with a 1 hour history of severe pain in his leg. On examination he has absent pulses in the affected limb and it is much cooler than the contra-lateral limb. Which process best accounts for this presentation? ``` Thrombosis Embolus Atheroma growth Sub intimal dissection Anaemia ```

In an existing lesion a complication such as thrombosis is more likely than embolus. These patients should receive heparin and imaging with duplex scanning. Whilst an early surgical bypass or intra-arterial thrombolysis may be indicated, an embolectomy should not generally be performed as the lesion is not an embolus and the operation therefore ineffective.

The following are true of carcinoid tumours except: When present in the appendix tip and measure less than 2 cm have an excellent prognosis Even when metastatic disease is present it tends to follow a protracted course When present in the appendix body tend to present with carcinoid syndrome even when liver metastases are not present May be imaged using somatostatin receptor scintigraphy scanning Advanced appendiceal carcinoids may require right hemicolectomy

Liver metastases are necessary for the presence of carcinoid syndrome.

During a difficult femoro-popliteal bypass operation the surgeon inadvertently places a clamp across the femoral nerve. It remains there for most of the procedure. At the end of the operation the nerve is inspected, it is in continuity but has evidence of being crushed. Which of the following is most likely to occur over the following weeks? Wallerian degeneration Rapid restoration of neuronal function because the axon itself is intact Normal but delayed neuronal transmission due to disruption of the myelin Absence of neuroma formation None of the above

A neuronal injury such as this will result in Wallerian degeneration even though the nerve remains in continuity. Neuromas may well form.

A 38 year old lady who smokes heavily presents with recurrent episodes of infection in the right breast. On examination she has an indurated area at the lateral aspect of the nipple areaolar complex. Imaging shows no mass lesions. What is the most likely diagnosis? ``` Duct ectasia Periductal mastitis Pagets disease of the nipple Mondors disease of the breast Radial scar ```

Periductal mastitis is common in smokers and may present with recurrent infections. Treatment is with co-amoxyclav. Mondors disease of the breast is a localised thrombophlebitis of a breast vein.

A 16 year-old boy presents to his GP with loss of weight, pain and fever. On examination, a mass is palpable over the mid-thigh region. What is the most likely diagnosis? ``` Fibrosarcoma Osteosarcoma Ewing sarcoma Osteoid osteoma Synovial sarcoma ```

Ewing's sarcoma is a malignant round cell tumour occurring in the diaphysis of the long bones in the children. These are not confined to the ends of long bones. X- Rays often show a large soft-tissue mass with concentric layers of new bone formation ( 'onion-peel' sign). The ESR may be elevated, thus suggesting an inflammatory or an infective cause such as osteomyelitis; although osteomyelitis usually affects the metaphyseal region in children. Treatment is with chemotherapy and surgical excision, an endoprothesis may be used to conserve the limb.

A 32 year old lady undergoes a thyroidectomy for a mild goitre. The resected specimen shows an intense lymphocytic infiltrate with acinar destruction and fibrosis. What is the underlying lesion? ``` Anaplastic carcinoma Rhadomyosarcoma Lymphoma Hashimotos thyroiditis Graves disease ```

Lymphocytic infiltrates and fibrosis are typically seen in Hashimotos thyroiditis. In lymphoma only dense lymphatic type tissue is usually present.

Which of the following statements relating to chronic inflammation is true? Chronic inflammation is mainly secondary to acute inflammation Neutrophils are the predominant cells involved Growth factors are not involved in the process Appendicitis is mainly a form of chronic inflammation Fibrosis is a macroscopic feature

``` Macroscopic features include: Ulcers Fibrosis Granulomatous process It most commonly occurs as a primary event rather than as a result of acute inflammation. ```

Which of the following statements relating to neutrophil polymorphs is true? Produce nitrogen peroxide as a microbicidal agent Not involved in opsonisation Deficiency leads to AIDS Neutrophil disorders may result in chronic granulomatous diseases Have a lifespan of 9 hours

Neutrophil disorders may result in chronic granulomatous diseases Neutrophils are the main cells of acute inflammation, important action against gram -ve and +ve bacteria Appearance of segmented nucleus and granulated cytoplasm Have a lifespan of 1-3 days (shorter when consumed during septic process, though 9 hours is unusual) Actions include: movement, opsonise microorganisms, phagocytosis & intracellular killing of microorganisms via aerobic (produce HYDROGEN PEROXIDE) & anaerobic mechanisms. Neutrophil disorders include chronic granulomatous diseases: rare AIDS associated with T cell deficiency

You review a 42-year-old woman 8 months following a renal transplant for focal segmental glomerulosclerosis. She is on a combination of tacrolimus, mycophenolate, and prednisolone. She has now presented with a five day history of feeling generally unwell with jaundice, fatigue and arthralgia. On examination she has jaundice, widespread lymphadenopathy and hepatomegaly. What is the most likely diagnosis? ``` Hepatitis C Epstein-Barr virus HIV Hepatitis B Cytomegalovirus ```

Post transplant lymphoproliferative disorder is most commonly associated with Epstein-Barr virus. It typically occurs 6 months post transplant and is associated with high dose immunosupressant therapy. Remember cytomegalovirus presents within the first 4 weeks to 6 months post transplant.

Which of the following processes facilitates phagocytosis? ``` Apoptosis Opsonisation Proteolysis Angiogenesis Necrosis ```

Opsonisation will facilitate phagocytosis. The micro-organism becomes coated with antibody, C3b and certain acute phase proteins. The macrophages and neutrophils have up regulation of phagocytic cell surface receptors in these circumstances, a process mediated by pro-inflammatory cytokines. These cells then engulf the micro organism.

Features which are evaluated for the grading of breast cancer include all the following, except: ``` Tubule formation Mitoses Nuclear pleomorphism Tumour necrosis Coarse chromatin ```

The necrosis of a tumour may be suggestive of a high grade tumour which has out grown its blood supply. However, the grading of breast cancer which classically follows the Bloom -Richardson grading model will tend to favor nuclear appearances (which include mitoses, coarse chromatin and pleomorphism). Tubule formation is an important marker of the degree of differentiation with formation of tubular structures being associated with well differentiated tumours.

A 34 year old man is diagnosed with an aggressive caecal adenocarcinoma. His sister died from the same disease at 38 years of age. His mother died from endometrial cancer at the age of 41. What is the most likely underlying abnormality? ``` Familial adenopolypomatosis coli Gardeners syndrome Mutation of mismatch repair genes Deletion of chromosome 6 MYH gene mutation ```

Mutation of mismatch repair genes Lynch syndrome which is characterised by aggressive right sided colonic malignancy and endometrial cancer is caused by microsatellite instability of DNA repair genes.

A 22 year old man presents with carcinoma of the caecum. His brother died from colorectal cancer aged 25. Which of the non GI cancers listed below are close relatives at greatest risk of developing? ``` Glioma Soft tissue sarcoma Endometrial cancer Ovarian cancer Fallopian tube cancer ```

This is a case of Lynch syndrome HNPCC. It is transmitted in an autosomal dominant fashion. Cancer of the uterine body is more common in HNPCC than Gardners syndrome. The fact that the patient is male is irrelevant as female relatives can still go on to develop endometrial cancers.

Which of the following is associated with poor wound healing? ``` Jaundice Patients taking carbamazepine General anaesthesia using thiopentone General anaesthesia using ketamine Multiple sclerosis ```

Jaundice Multiple sclerosis is associated with pressure sores, however the cellular healing process is not affected.

Which of the disorders listed below is characterized by a PTEN mutation and intestinal hamartomas? ``` Familial adenomatous polyposis coli MYH associated polyposis Peutz-Jeghers syndrome Cowden disease Lynch syndrome ```

Cowden disease PTEN is a tumour suppressor gene and loss of function mutations result in up regulation of the mTOR pathway.

A 55 year old man undergoes a colonoscopy and a colonic polyp is identified. It has a lobular appearance and is located on a stalk in the sigmoid colon. Which of the processes below best accounts for this finding? ``` Apoptosis Metaplasia Dysplasia Calcification Degeneration ```

Most colonic polyps described above are adenomas. These may have associated dysplasia. The more high grade the dysplasia the greater the level of clinical concern.

A 56 year old lady has just undergone a colonoscopy and a 1.5cm lesion was identified in the caecum. The histology report states that biopsies have been taken from a sessile serrated polyp with traditional features. What is the best management option? ``` Perform a right hemicolectomy List the patient for colonoscopic polypectomy Discharge the patient Re scope the patient in 6 months Re scope the patient at 3 years ```

List the patient for colonoscopic polypectomy These polyps represent an alternative pathway to progression to carcinoma and may be diagnostically confused with hyperplastic polyps. Hyperplastic polyps are more common in the left colon and confer no increased risk. SSA's are more common in the right colon and are usually larger. Those with "traditional features" on histology have dysplasia with increased risk of malignant transformation.