Acinar Adenocarcinoma

 

 

Common sites:

    •  

 

Gross features:

    • whitish flat areas

 

Histologic features:

    • small glands
    • absence of basal cell layer
    • infiltrative architecture (between normal glands)
    • nuclear atypia, prominent nucleoli
      • enlarged nuclei
      • hyperchromatism
      • mitotic figures (not necessary)
    • amphophilic cytoplasm
    • sharp luminal border
    • perineural invasion
    • may see signet ring cells in gleason 4 & 5 (no intracellular mucin)
    • minor criteria:
      • wispy blue mucin
      • pink amorphous secretions
      • intraluminal crystalloids
      • adjacent PIN
      • (2 more)
    • hyperplastic variant:
      • benign-appearing nuclei
      • large, complex glands
      • back to back architecture
    • neuroendocrine components may be present:
      • basally located deeply eosinophilic fine cytoplasmic granules
      • positive for PSA and PSAP
    • squamous differentiation may be present (more frequent in men treated with hormone therapy)
      • PSA / PSAP may be positive
      • pure squamous carcinoma is rare and has a poor survival

 

Immunophenotype:

Marker:

Sensitivity:

Specificity:

 34-Beta (HMWK)
(negative)

 

 

P63 (neg)

 

 

Racemase

 

 

Neuroendocrine markers (subset of cells – common finding)

 

 

 

Molecular features:

    •  

 

Other features:

    •  Reporting:
      • Needle cores / TURP / enucleation:
        • Each separate specimen (container) should have its own diagnosis line:
          • Ex. Invasive adenocarcinoma; Gleason score 7(3,4); 1/2 cores positive; 20% tissue involvement; periprostatic fat invasion present.
        • Optionally, an additional global (composite) Gleason score integrating all involved sites and overall tumour extent measure may also be given
        • If 3 Gleason patterns are present, list the most predominant pattern and the worst pattern of the remaining two.
        • If the secondary Gleason pattern is < 5%, only include it if it is higher than the primary Gleason pattern.  Otherwise, just double the primary Gleason pattern.
        • Tumour quantification (% of prostate tissue involved by tumour)
        • Number of cores positive / total number of cores
      • Prostatectomy:
        • If 3 patterns are present, record the 3rd only if it is higher than the first two
        • If 2 distinct tumours are present, report them separately, or at least report the higher grade of the two as the Gleason score.
        • Tumour quantification (% of prostate involved by tumour)
        • Tumour size (dominant nodule if present)
        • Margins involved:
          • Apical
          • Bladder neck
          • Anterior
          • Lateral
          • Postero-lateral (neurovascular bundle)
          • posterior
      • Extraprostatic extension
        • Tumour abutting on or admixed with fat
        • Perineural invasion in the neurovascular bundles
        • At the apex, tumour admixed with skeletal muscle DOES NOT constitute extraprostatic extension
      • Seminal vesicle invasion
        • Requires invasion of muscular wall
      • Perineural invasion
      • Lymphatic (small vessel) invasion
      • Margin status:
        • Tumour cells must be touching the ink to be a positive margin
      • Additional findings (optional):
        • High-grade PIN (important in some settings)
        • Atypical adenomatous hyperplasia (adenosis)
        • Inflammation
        • Nodular prostatic hyperplasia

 

References:

    • Robbins 2005
    • Sternberg 2004