Long power list

The long power list is a collection of diagnoses based on site and pathologic characteristics. It builds on the short power list.

Site

Bone & cartilage

General

Benign - bone:

• Aneurysmal bone cyst.
• Brown tumour.
• Paget's disease of bone.
• Osteomyelitis.
• Fibrous dysplasia.

Benign - bone tumours:

• Osteoid osteoma.
• Osteoblastoma.
• Osteochondroma.
• Adamantinoma.

Benign - cartilage:

• Chondroma.
• Enchondroma.
• Chondroblastoma.

Malignant - bone:

• Metastatic carcinoma.
• Plasma cell neoplasm.
• Osteosarcoma.
• Ewing sarcoma.
• Giant cell tumour of bone.

Malignant - cartilage:

• Chondrosarcoma.

Unusual genetic conditions:

• Langerhans cell histiocytosis.
• Gaucher disease.

Femoral head

Benign:

• Osteoarthritis.
• Avascular necrosis of the femoral head.
• Rheumatoid arthritis.

Uncommon - benign (fracture):

• Trauma.
• Osteoporosis.

Uncommon - benign pediatric:

• Slipped capital femoral epiphysis (SCFE).
• Legg–Calvé–Perthes syndrome.

Uncommon - malignant (fracture):

• Metastasis.

Breast pathology

Benign - common:

• Normal.
• Fibrocystic change.
• Apocrine metaplasia.
• Columnar cell change.
• Fibroadenoma.
• Phyllodes tumour.
• Intraductal papilloma of the breast.
• Florid epithelial hyperplasia.
• Sclerosing adenosis.

Benign - uncommon:

• Flat epithelial atypia.
• Complex sclerosing lesion.
• Breast abscess.
• Breast with fat necrosis.
• Microglandular adenosis.
• Collagenous spherulosis.
• Lactational change.
• Diabetic mastopathy.

Non-invasive:

• ADH.
• DCIS.
  • Subtypes: cribriform, solid, papillary, micropapillary.
• ALH.
• LCIS.

Invasive - epithelial:

• Invasive ductal carcinoma of the breast.
• Invasive lobular carcinoma.
• Papillary carcinoma of the breast.
• Invasive micropapillary carcinoma of the breast.
• Invasive cribriform carcinoma of the breast.
• Tubular carcinoma of the breast.
• Medullary breast carcinoma.
• Mucinous breast carcinoma.
• Metaplastic breast carcinoma.

Invasive - non-epithelial:

• Phyllodes tumour.
• Angiosarcoma.

Invasive - salivary gland-like:

• Adenoid cystic carcinoma of the breast.
• Carcinoma ex pleomorphic adenoma of the breast.

Cardiovascular pathology

General

• Thrombosis (embolism).
• Vasculitis.
  • Large vessel:
    • Giant cell arteritis.
    • Takayasu arteritis.
  • Medium vessel:
    • Polyarteritis nodosa.
    • Kawasaki disease.
  • Small vessel:
    • Microscopic polyangiitis.
    • Granulomatosis with polyangiitis (Wegener's granulomatosis).
    • Eosinophilic granulomatosis with polyangiitis (Churg-Strauss syndrome).
    • Leukocytoclastic vasculitis.
• Amyloid deposition.
• Hyperplastic arteriolosclerosis.
• Fibromuscular dysplasia.

Aorta

• Atherosclerosis.
• Aortic dissection.
  • Cystic medial degeneration.
  • Traumatic dissection - see blunt force injury.
• Mycotic aneurysm.

Cardiac valves

• Infective endocarditis.
• Myxomatous degeneration.
• Papillary fibroelastoma.

Aortic valve

• Calcific aortic stenosis.

Mitral valve

• Rheumatic heart disease.

Tricuspid valve

• Nonbacterial thrombotic endocarditis (NBTE).

Heart

Common - benign:

• Atrial myxoma.

Uncommon - benign:

• Lipoma.
• Rhabdomyoma.

Uncommon - malignant:

• Pleomorphic undifferentiated sarcoma.
• Angiosarcoma.

Dermatopathology

Benign - non-melanocytic:

• Epidermal inclusion cyst.
• Pilar cyst.
• Steatocystoma.
• Lipoma.
• Dermatofibroma.
• Dermal scar.
• Trichoepithelioma (trichoblastoma).
• Clear cell acanthoma.
• Leiomyoma.

Benign melanocytic lesions:

• Intradermal nevus.
• Junctional nevus.
• Congenital nevus.
• Clark nevus.
• Spitz nevus.
• Pigmented spindle cell nevus of Reed.
• Blue nevus.

Inflammatory skin lesions:

• Bullous diseases:
  • Pemphigus vulgaris.
  • Dermatitis herpetiformis.
• Interface dermatitis:
  • Lupus erythematosus.
  • Lichen planus.
• Nodular & diffuse:
  • Cutaneous T-cell lymphoma.
  • Granuloma annulare.
  • Necrobiosis lipoidica.
• Psoriasiform diseases:
  • Psoriasis vulgaris.
  • Lichen simplex chronicus.
• Panniculitis:
  • Erythema nodosum.
  • Erythema induratum.
• Vasculitides:
  • Leukocytoclastic vasculitis.

Malignant:

• Basal cell carcinoma.
• Squamous cell carcinoma.
• Malignant melanoma.
• Merkel cell carcinoma.
• Dermatofibrosarcoma protuberans.
• Atypical fibroxanthoma.
• Leiomyosarcoma.
• Metastasis.

Endocrine pathology

Thyroid gland

Benign:

• Nodular hyperplasia.
• Lymphocytic thyroiditis.
  • Hashimoto thyroiditis.
• Noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP).

Benign - uncommon:

• Hyalinizing trabecular tumour.
• Subacute thyroiditis.

Malignant:

• Papillary thyroid carcinoma follicular variant.
• Papillary thyroid carcinoma.

Malignant - uncommon:

• Papillary thyroid carcinoma columnar cell variant.
• Papillary thyroid carcinoma tall cell variant.
• Papillary thyroid carcinoma cribriform-morular variant.
• Papillary thyroid carcinoma diffuse sclerosing variant.
• Medullary thyroid carcinoma.
• Anaplastic thyroid carcinoma.

Thyroid gland - cytology

• Benign.
• Follicular lesion of undetermined significance (FLUS).
• Follicular neoplasm.
• Suspicious for malignancy.
• Malignant, e.g. papillary thyroid carcinoma.
• Nondiagnostic or unsatisfactory.

Parathyroid gland

Benign:

• Parathyroid hyperplasia.
• Parathyroid adenoma.

Malignant - rare:

• Parathyroid carcinoma.

Adrenal gland

Benign:

• Adrenal cortical adenoma.
• Adrenal myelolipoma.
• Hemorrhagic adrenalitis (Waterhouse-Friderichsen syndrome).
• Adrenal ganglioneuroma.
• Neuroblastoma - pediatric pathology.
• Tuberculosis.

Malignant:

• Adrenal cortical carcinoma.
• Pheochromocytoma.
• Metastasis.

Gastrointestinal pathology

Gastrointestinal polyp

Benign:

• Normal.
• Hyperplastic polyp.
• Inflammatory pseudopolyp (inflammatory bowel disease).

Pre-malignant:

• Tubular adenoma.
• Villous adenoma.
• Tubulovillous adenoma.
• Sessile serrated adenoma.

Uncommon - pre-malignant:

• Traditional serrated adenoma.

Uncommon - benign:

• Peutz-Jeghers polyp.
• Juvenile polyp.
• Inflammatory fibroid polyp.

Malignant:

• Adenocarcinoma.
  • Colorectal adenocarcinoma.

Esophagus

Benign:

• Gastroesophageal reflux disease.
• Eosinophilic esophagitis.
• Barrett esophagus.

Benign - uncommon:

• Candida esophagitis.
• Herpes esophagitis.

Tumour:

• Leiomyoma.
• Gastrointestinal stromal tumour - may be malignant.
• Granular cell tumour - may be malignant.

Malignant:

• Squamous cell carcinoma of the esophagus
• Adenocarcinoma.

Stomach

Benign:

• Helicobacter pylori gastritis.
• Intestinal metaplasia.
• Chronic gastritis.
• Acute gastritis.

Pre-malignant:

• Gastric dysplasia.

Malignant:

• Epithelial:
  • Adenocarcinoma, intestinal-type.
  • Adenocarcinoma, diffuse-type.
    • Signet-ring cell carcinoma.
  • Metastatic carcinoma.
  • Neuroendocrine tumour.
• Mesenchymal:
  • GIST.
• Hematopoietic:
  • MALT lymphoma.
  • Mantle cell lymphoma.
  • Diffuse large B-cell lymphoma.

Duodenum

Benign:

• Normal.
• Celiac disease.

Pre-malignant:

• Tubular adenoma.

Malignant:

• Duodenal adenocarcinoma.

Uncommon benign:

• Gastric heterotopia of the duodenum.
• Peptic ulcer disease.
• Acute duodenitis.
• Giardiasis.
• Whipple disease.
• MAI infection.
• Pseudomelanosis duodeni.

Colon/rectum

Benign:

• Normal.
• Colitis.
  • IBD - Crohn's disease, ulcerative colitis.
• Hyperplastic polyp.
• Tubular adenoma.
• Tubulovillous adenoma.
• Villous adenoma.
• Sessile serrated adenoma.

Benign - uncommon infectious:

• Pseudomembranous colitis.
• Cytomegalovirus colitis.
• Cryptosporidiosis.
• Strongyloidiasis.
• Intestinal spirochetosis.

Benign - uncommon:

• Lymphocytic colitis.
• Collagenous colitis.
• Inflammatory polyp.
• Juvenile polyp.
• Peutz-Jeghers polyp.
• Solitary rectal ulcer.
• Melanosis coli.
• Radiation colitis.
• Diversion colitis.

Tumour:

• Gastrointestinal stromal tumour.
• Schwannoma.
• Lipoma.
• Neuroendocrine tumour.

Malignant:

• Colorectal adenocarcinoma.
  • Medullary carcinoma.
  • Mucinous carcinoma.
  • Signet ring carcinoma.
• Goblet cell carcinoid.
• Metastatic tumours.

Appendix

Benign:

• Appendicitis.
• Periappendicitis.
• Crohn's disease.
• Normal.

Benign - uncommon:

• Enterobius vermicularis.
• Granulomatous appendicitis.

Neoplasm:

• Neuroendocrine tumour.
• Low-grade appendiceal mucinous neoplasm (LAMN).

Malignant:

• Mucinous adenocarcinoma of the appendix.
• Goblet cell carcinoid.

Liver

Benign:

• Steatosis.
• Steatohepatitis.
• Hepatitis B.
• Hepatitis C.

Benign - tumour:

• Hepatic hemangioma.
• Focal nodular hyperplasia.
• Hepatocellular adenoma.

Malignant:

• Liver metastasis - usually metastatic adenocarcinoma.
• Hepatocellular carcinoma.

Uncommon benign:

• Alpha-1 antitrypsin deficiency.
• Autoimmune hepatitis.
• Primary sclerosing cholangitis, especially in the context of UC.
• Primary biliary cholangitis.
• Wilson's disease.
• Hereditary hemochromatosis.
• Hepatic infarct.
• Hepatitis A.

Uncommon malignant:

• Cholangiocarcinoma.
• Angiosarcoma.
• Epithelioid hemangioendothelioma.

Gallbladder

Benign:

• Cholelithiasis.
• Cholesterolosis.
• Acute cholecystitis.
• Chronic cholecystitis.
• Intestinal metaplasia.

Uncommon - pre-malignant:

• Gallbladder adenoma.

Uncommon - malignant:

• Carcinoma of the gallbladder.

Genitourinary pathology

Tumour kidney

Benign:

• Normal kidney.
• Renal oncocytoma.
• Angiomyolipoma.
• Papillary adenoma.
• Clear cell papillary renal cell tumour (previously clear cell papillary renal cell carcinoma or clear cell tubulopapillary renal cell carcinoma).
• Renal medullary fibroma.

Malignant - common:

• Clear cell renal cell carcinoma.
• Papillary renal cell carcinoma.
• Chromophobe renal cell carcinoma.
• Urothelial carcinoma.

Malignant - less common:

• Collecting duct carcinoma.
• Renal tumour with Xp11.2 translocation.
• SMARCB1-deficient renal medullary carcinoma.
• Renal mucinous tubular and spindle cell carcinoma.
• SDH-deficient renal cell carcinoma.
• Hereditary leiomyomatosis and renal cell carcinoma syndrome-associated renal cell carcinoma.
• Acquired cystic disease-associated renal cell carcinoma.
• Renal hybrid oncocytic/chromophobe tumour.
• Tubulocystic renal cell carcinoma.
• Unclassified renal cell carcinoma.
• ALK-rearranged renal cell carcinoma.

Possibly benign:

• Multilocular cystic renal neoplasm of low malignant potential.

Uncommon - benign:

• Xanthogranulomatous pyelonephritis.
• Chronic pyelonephritis.
• Eosinophilic vacuolated tumour.
• Mixed epithelial stromal tumour.
• Cystic nephroma.
• Metanephric adenoma.
• Low-grade oncocytic tumour.

Children - tumours:

• Wilms tumour.
• Clear cell sarcoma of the kidney.
• Metanephric stromal tumour.
• Metanephric adenofibroma.
• Mesoblastic nephroma.
• Renal rhabdoid tumour.
• Renal tumour with t(6;11) translocation.

Medical kidney

Important/common:

• Diabetic nephropathy.
• Systemic lupus erythematosus.

Nephrotic syndrome:

• Minimal change disease.
• Focal segmental glomerulosclerosis.
• Membranous nephropathy.

Nephritic syndrome:

• Post-infectious glomerulonephritis.
• IgA nephropathy.
• Lupus nephritis.
• Antiglomerular basement membrane disease.
• Wegener's granulomatosis.

Mixed presentation:

• Membranoproliferative glomerulonephritis (MPGN).

Cystic disease:

• Autosomal dominant polycystic kidney disease (ADPKD).
• Acquired renal cystic disease.
• Autosomal recessive polycystic kidney disease.

Others:

• Fibrillary glomerulopathy.
• Renal amyloidosis.
• Thin glomerular basement membrane disease.
• Alport syndrome.
• Fabry's disease.
• Thrombotic microangiopathy.
• End-stage kidney.

Prostate gland

Benign:

• Normal.
• Chronic inflammation.
• Acute inflammation.
• Benign prostatic hyperplasia (prostectomy diagnosis only).
• Granulomatous prostatitis.

Pre-malignant:

• High-grade prostatic intraepithelial neoplasia.

Suspicious:

• Atypical small acinar proliferation (atypical glands, suspicious).

Malignant:

• Acinar adenocarcinoma.

Waffle category:

• Prostatic stromal tumour of uncertain malignant potential.

Uncommon - malignant:

• Ductal adenocarcinoma of the prostate.
• Urothelial carcinoma.
• Mucinous prostate carcinoma.
• Prostatic signet ring cell carcinoma.
• Sarcomatoid prostate carcinoma.
• Small cell carcinoma of the prostate gland.
• Adenoid cystic/basal cell carcinoma of the prostate.
• Prostatic stromal sarcoma.

Mimic benign:

• Foamy gland carcinoma.
• Pseudohyperplastic adenocarcinoma.
• Atrophic prostate carcinoma.
• PIN-like prostatic ductal adenocarcinoma - mimics HGPIN.

Urinary bladder

Benign:

• Inverted urothelial papilloma.
• Cystitis cystica.
• Nephrogenic adenoma.

Pre-malignant/malignant:

• Urothelial dysplasia.
• Urothelial carcinoma in situ.
• Low grade papillary urothelial carcinoma.
• High grade papillary urothelial carcinoma.
• Flat urothelial carcinoma.

Uncommon - benign:

• Malakoplakia.
• Giant cell cystitis.

Urine - cytology

Common:

• Negative for malignancy.
• Urothelial carcinoma.
• Polyomavirus.

Uncommon:

• Squamous cell carcinoma.
• Adenocarcinoma.

Testis

Non-neoplastic:

• Testicular abscess.
• Testicular atrophy.
• Testicular scar.
• Sertoli cell nodule (Pick's adenoma).

Pre-neoplastic:

• Germ cell neoplasia in situ (intratubular germ cell neoplasia).

Common tumours:

• Seminoma.
• Embryonal carcinoma.
• Yolk sac tumour.
• Teratoma.
• Mixed germ cell tumour.

Less common tumours:

• Sertoli cell tumour.
• Leydig cell tumour.
• Lymphoma.
• Choriocarcinoma.
• Spermatocytic tumour.
• Malignant mesothelioma.
• Liposarcoma.
• Adenocarcinoma of the rete testis.

Associated with testis

• Spermatocele.
• Hydrocele testis.
• Vasitis nodosa.
• Fibrous pseudotumour of the paratesticular region.

Epididymis:

• Papillary cystadenoma of the epididymis.
• Serous cystadenoma of the epididymis.

Gynecologic pathology

Uterus

Benign:

• Fibroids.
• Adenomyosis.
• Atrophic endometrium.
• Uterine prolapse.
• Proliferative phase endometrium.
• Secretory phase endometrium.
• Disordered proliferative endometrium.

Pre-malignant:

• Simple endometrial hyperplasia.
• Simple endometrial hyperplasia with atypia.
• Complex endometrial hyperplasia.
• Complex endometrial hyperplasia with atypia.

Malignant:

• Endometrial carcinoma.
  • Endometrioid endometrial carcinoma.
  • Mucinous endometrial carcinoma.
  • Serous endometrial carcinoma.

Uncommon - benign:

• Decidua (change of pregnancy).
• Arias-Stella reaction.

Uncommon - malignant:

• Clear cell endometrial carcinoma.
• Carcinosarcoma.
• Endometrial stromal sarcoma.

Cervix - cytology

Main article: Gynecologic cytopathology

Benign:

• Normal.
• Candida.
• Endometrial cells >40 years.

Benign not typically reported:

• Atrophy.
• Reactive changes.
• Squamous metaplasia.
• Tubal metaplasia.
• Endometrial cells <40 years.

Uncommon - benign:

• HSV changes.
• Trichomonas.
• Bacterial vaginosis.
• Actinomycetes.

Waffle diagnoses:

• Atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesion (ASC-H).
• Atypical squamous cells of undetermined significance (ASC-US).
• Atypical glandular cells (AGC).

Pre-malignant/malignant:

• LSIL.
• HSIL.
• Squamous cell carcinoma.
• Adenocarcinoma in situ.
  • Endocervical.
  • Endometrial.
  • Other.

Ovary

Benign:

• Serous cystadenoma of the ovary.
• Mucinous cystadenoma of the ovary.
• Mature teratoma.
• Endometriosis.

Malignant:

• Serous carcinoma of the ovary.
• Endometrioid carcinoma of the ovary.
• Mucinous carcinoma.

Uncommon - malignant:

• Dysgerminoma.
• Clear cell carcinoma of the ovary.
• Choriocarcinoma.

Other tumours:

• Leydig cell tumour.
• Sertoli-Leydig cell tumour.
• Adult granulosa cell tumour.
• Juvenile granulosa cell tumour.
• Thecoma.
• Sex cord tumour with annular tubules.
• Ovarian fibroma.
• Brenner tumour.

Fallopian tube

Benign:

• Paratubal cyst.
• Tubo-ovarian abscess.
• Salpingitis.
• Ectopic pregnancy.
• Adenomatoid tumour.

Malignant:

• Serous carcinoma.

Uncommon - benign:

• Salpingitis isthmica nodosa.

Head and neck

General

Benign:

• Sinonasal papilloma.
• Vocal cord nodule.

Malignant:

• Squamous cell carcinoma of the head and neck.
• Nasopharyngeal carcinoma.
• HPV-associated squamous cell carcinoma of the head and neck.

Uncommon - malignant:

• Paraganglioma (carotid body tumour).

Salivary gland

Benign:

• Pleomorphic adenoma.
• Warthin tumour.
• Basal cell adenoma.
• Oncocytoma of the salivary gland.
• Canalicular adenoma.

Malignant:

• Mucoepidermoid carcinoma.
• Adenoid cystic carcinoma.

Uncommon benign:

• Benign lymphoepithelial cyst.
• Basal cell adenoma.
• Canalicular adenoma.
• Oncocytoma.

Uncommon malignant:

• Acinic cell carcinoma.
• Polymorphous adenocarcinoma - previously known as polymorphous low-grade adenocarcinoma.
• Carcinoma ex pleomorphic adenoma.
• Salivary duct carcinoma.
• Hyalinizing clear cell carcinoma.
• Epithelial-myoepithelial carcinoma.
• Secretory carcinoma of the salivary gland (mammary analogue secretory carcinoma).
• Human papillomavirus-related multiphenotypic sinonasal carcinoma (HPV-related carcinoma with adenoid cystic-like features).

Lymph node

Benign:

• Normal/resting.
• Reactive follicular hyperplasia.
• Sinus histiocytosis.
• Hyalinized lymph node.

Malignant:

• Metastasis, esp. carcinoma.
• Follicular lymphoma.
• Chronic lymphocytic leukemia/Small cell lymphoma.
• Diffuse large B cell lymphoma.
• Nodular sclerosis Hodgkin lymphoma.
• Mixed cellularity Hodgkin lymphoma.
• Nodular lymphocyte predominant Hodgkin lymphoma.
• Lymphocyte-rich Hodgkin lymphoma.
• Lymphocyte-depleted Hodgkin lymphoma.
• Marginal zone lymphoma.

Benign - uncommon:

• Castleman disease.
• Progressive transformation of germinal centers.
• Dermatopathic lymphadenopathy.
• Sarcoidosis.
• Tuberculosis.
• Cat-scratch disease.
• Rosai-Dorfman disease.
• Kimura disease.
• Toxoplasmosis.
• Intranodal palisaded myofibroblastoma.

Neuropathology

Brain

Benign:

• Epidural hemorrhage.
• Subdural hemorrhage.
• Subarachnoid hemorrhage.
• Intracerebral hemorrhage.
• Duret hemorrhage.
• Hypoxic-ischemic encephalopathy.
• Multiple sclerosis.
• Colloid cyst.
• Cerebral amyloid angiopathy.

Pediatric - tumour:

• Pilocytic astrocytoma.
• Neuroblastoma.
• Retinoblastoma.
• Ependymoma.

Adult - tumour:

• Meningioma.
• Schwannoma.
• Diffuse astrocytoma.
• Anaplastic astrocytoma.
• Glioblastoma.
• Myxopapillary ependymoma.
• Pituitary adenoma.
• Adamantinomatous craniopharyngioma.
• Papillary craniopharyngioma.
• Oligodendroglioma.
• Brain metastasis.

Neurodegenerative

• Alzheimer disease.
• Creutzfeldt-Jakob disease.

• Parkinson disease.
• Multiple system atrophy.
• Dementia with Lewy bodies.
• Multiple system atrophy.

• Chronic traumatic encephalopathy.
• Huntington disease.

Muscle

• Dermatomyositis.
• Polymyositis.

• Muscular dystrophy.
• Amyotrophic lateral sclerosis.
• Inclusion body myositis.
• Drug-induced rhabdomyolysis.

Pulmonary pathology

Benign:

• Normal.
• Acute bronchopneumonia.
• Diffuse alveolar damage - acute phase, organizing phase, resolution.
• Emphysema - centrilobular, panlobular.
• Asthma.
• Aspiration pneumonia.
• Pulmonary meningothelial-like nodule.

Malignant:

• Adenocarcinoma.
• Squamous carcinoma of the lung.
• Small cell carcinoma of the lung.
• Lung metastasis.

Uncommon - granulomatous:

• Tuberculosis.
• Sarcoidosis.
• Fungal infections (e.g. aspergillosis).

Uncommon - benign other:

• Carcinoid tumourlet.
• Typical lung carcinoid tumour.
• Atypical lung carcinoid tumour.
• Solitary fibrous tumour - esp. pleural.
• Lymphangioleiomyomatosis.
• Pulmonary Langerhans cell histiocytosis.
• Bronchogenic cyst.
• Congenital pulmonary airway malformation (CPAM).
• Extralobar sequestration.
• Intralobar sequestration.
• Asbestosis.
• Silicosis.
• Coal worker's pneumonconiosis.
• Pulmonary alveolar proteinosis.
• Eosinophilic pneumonia.
• Goodpasture disease.
• Wegener's granulomatosis.
• Radiation pneumonitis.
• Drug toxicity, e.g. amiodarone, bleomycin.
• Infectious - blastomycosis, cryptococcosis, histoplasmosis, pneumocystis pneumonia.

Uncommon - vascular:

• Pulmonary hypertension.
• Vasculitides - see cardiovascular section.

Uncommon - idiopathic interstitial pneumonias:

• Usual interstitial pneumonia (UIP).
• Non-specific interstitial pneumonia (NSIP).
• Lymphocytic interstitial pneumonia (LIP).
• Cryptogenic organizing pneumonia (BOOP).
• Respiratory bronchiolitis-associated interstitial lung disease (RB-ILD).
• Desquamative interstitial pneumonia (DIP).

Uncommon - malignant:

• Malignant mesothelioma.

Spleen

Benign:

• Trauma.
• Normal.
• Enlargement due to cirrhosis or other causes of portal hypertension.
• Mononucleosis.

Benign - rare:

• Hemophagocytic syndrome.

Malignant - common:

• Diffuse large B-cell lymphoma.
• Splenic marginal zone lymphoma.
• Follicular lymphoma.

Malignant - others:

• Hairy cell leukemia.
• Hepatosplenic T-cell lymphoma.

Placenta

• Normal.
• Chorioamnionitis.
  • Funisitis.
• Meconium.
• Placentomegaly.
• Placental infarction.

Less common:

• TORCH infections.
• Chorangioma.
• Chorangiosis.
• Villitis of unknown etiology.
• Chronic intervillitis.
• Two vessel umbilical cord.
• Maternal floor infarction.
• Fetal thrombotic vasculopathy.
• Hypertrophic decidual vasculopathy.

Pathologic characteristics

Non-skin tumours with skin

• Salivary gland tumours.
• Breast tumours.

Nodule-forming lymphoma

Malignant:

• Follicular lymphoma.
• Small cell lymphoma.
• Nodular lymphocyte predominant Hodgkin lymphoma.
• Mantle cell lymphoma.

Nuclear features

Pseudostratified nuclei

Tumours that commonly have pseudostratified nuclei:

• Colorectal carcinoma.
• Endometrioid endometrial carcinoma.

Pseudoinclusions

Main article: Nuclear pseudoinclusions

Cytoplasmic features

Eosinophilic cytoplasm

• Squamous cell carcinoma.
• Oncocytoma/oncocytic tumours.
• Apocrine tumours.
• Anaplastic large cell lymphoma.

Clear cytoplasm

Main article: Clear cell tumours

Cells

Tumours with lymphocytes

• Seminoma.
• Acinic cell carcinoma.
• Nasopharyngeal carcinoma.
• Lymphoepithelioma-like carcinoma.
• Medullary breast carcinoma.
• Thymoma.
• Lymphoma - Hodgkin and non-Hodgkin.
• Follicular dendritic cell sarcoma.

Giant cells

Main article: Giant cell lesions

Many eosinophils

• Infection - esp. fungal.
• Drug reaction.
• Inflammatory fibroid polyp.
• Hodgkin lymphoma.
• Churg-Strauss syndrome.
• Langerhans cell histiocytosis.
• Kimura disease.

Site specific:

• Eosinophilic esophagitis.
• Eosinophilic gastritis.
• Eosinophilic colitis.
• Pulmonary Langerhans cell histiocytosis.
• Angiolymphoid hyperplasia with eosinophilia (ALHE) - skin.

Red blood cell extravasation

• Hemorrhage.
• Vasculitis.
• Nodular fasciitis.
• Intranodal palisaded myofibroblastoma.
• Kaposi sarcoma.

Structures

Psammoma bodies

Main article: Psammoma bodies

Myxoid lesions

Main article: Myxoid lesions

Architecture

Classically nested

• Paraganglioma.
• Meningioma.
• Brenner tumour.
• SCTAT.

Stroma rich tumours

• Cholangiocarcinoma.
• Fibrolamellar hepatocellular carcinoma.
• Mesothelioma - lung.
• Hyalinizing trabecular tumour - thyroid.
• Hyalinizing clear cell carcinoma - salivary gland.

Spindle cell lesions

Main article: Spindle cell lesions

Spindle cell lesions in neuropathology

• Schwannoma.
• Gliosarcoma.

Frustration lists

The following are diagnoses to think about if the answer isn't apparent.

General frustration list

If the pathology isn't apparent...

• Neurofibroma.
• Amyloidosis.
• Granular cell tumour.
• Adenomatoid tumour.
• Angiosarcoma.
• Pheochromocytoma.
• Plasma cell neoplasm.

Memory device: NAGAAPP.

CNS frustration list

• Meningioma.

Head & neck frustration list

• Myoepithelioma.
• Mucoepidermoid carcinoma.
• Polymorphous low-grade adenocarcinoma.

Colonic biopsies frustration list

• CMV colitis.
• Cryptosporidiosis.
• Intestinal spirochetosis.
• Lymphocytic colitis.
• Collagenous colitis.

See also

• Short power list.
• Diagnoses.