The Microscope as a Tool for Disease Discovery-A Personal Voyage

Of drills and bones: Giovanni Ghedini and the origin of bone marrow biopsy

Bone marrow (BM) studies are pivotal for the diagnosis of haematological disorders. Their introduction into clinical haematology dates back to the work of Giovanni Ghedini (1877-1959), an Italian physician who first conceived BM sampling in 1908. Ghedini's proposal stemmed from his clinical experience and from the scientific developments that characterised his epoch. By presenting selected passages of Ghedini's publications, this report considers the theoretical and historical bases of his work and analyses its practical implications for modern haematology.

A hypothesis on paradoxical privileged portal vein metastasis of hepatocellular carcinoma. Can organ evolution shed light on patterns of human pathology, and vice versa?

Unlike other carcinomas, hepatocellular carcinoma (HCC) metastasizes to distant organs relatively rarely. In contrast, it routinely metastasizes to liver vasculature/liver, affecting portal veins 3-10 times more often than hepatic veins. This portal metastatic predominance is traditionally rationalized within the model of a reverse portal flow, due to accompanying liver cirrhosis. However, this intuitive model is not coherent with facts: 1) reverse portal flow occurs in fewer than 10% of cirrhotic patients, while portal metastasis occurs in 30-100% of HCC cases, and 2) portal vein prevalence of HCC metastasis is also characteristic of HCC in non-cirrhotic livers. Therefore, we must assume that the route for HCC metastatic dissemination is the same as for other carcinomas: systemic dissemination via the draining vessel, i.e., via the hepatic vein. In this light, portal prevalence versus hepatic vein of HCC metastasis appears as a puzzling pattern, particularly in cases when portal HCC metastases have appeared as the sole manifestation of HCC. Considering that other GI carcinomas (colorectal, pancreatic, gastric and small bowel) invariably disseminate via portal vein, but very rarely form portal metastasis, portal prevalence of HCC metastasis appears as a paradox. However, nature does not contradict itself; it is rather our wrong assumptions that create paradoxes. The 'portal paradox' becomes a logical event within the hypothesis that the formation of the unique portal venous system preceded the appearance of liver in evolution of chordates. The analysis suggests that the appearance of the portal venous system, supplying hormones and growth factors of pancreatic family, which includes insulin, glucagon, somatostatin, and pancreatic polypeptide (HGFPF) to midgut diverticulum in the early evolution of chordates (in an Amphioxus-like ancestral animal), promoted differentiation of enterocytes into hepatocytes and their further evolution to the liver of vertebrates. These promotional-dependent interactions are conserved in the vertebrate lineage. I hypothesize that selective homing and proliferation of malignant hepatocytes (i.e., HCC cells) in the portal vein environment are due to a uniquely high concentration of HGFPF in portal blood. HGFPF are also necessary for liver function and renewal and are significantly extracted by hepatocytes from passing blood, creating a concentration gradient of HGFPF between the portal blood and hepatic vein outflow, making post-liver vasculature and remote organs less favorable spaces for HCC growth. It also suggested that the portal vein environment (i.e., HGFPF) promotes the differentiation of more aggressive HCC clones from already-seeded portal metastases, explaining the worse outcome of HCC with the portal metastatic pattern. The analysis also offers new hypothesis on the phylogenetic origin of the hepatic diverticulum of cephalochordates, with certain implications for the modeling of the chordate phylogeny.

[Recovery of paraffin blocks and central archiving : Experiences of the Kiel lymph node registry and the German study group for Hodgkin lymphoma]

BACKGROUND

Central collection of tissue blocks for pathological and translational research is particularly important in rare diseases. Transfer of tissue blocks from primary to central pathology is of crucial importance.

OBJECTIVES

We aimed to answer the following questions: Has the transfer of tissue blocks sent for consultation or within clinical trials changed over the last 20 years? What are the reasons for reclaiming tissue blocks by the primary pathology and what actions would convince primary pathologists to leave the blocks in the reference pathology?

MATERIAL AND METHODS

The first 100 biopsies of each year between 1995 and 2015 (n = 2100), as well as all tissue transfers within therapeutic studies (n = 1405, German Hodgkin Study Group, GHSG) between 1998 and 2015, were analyzed separately for block reclaims using the Department of Pathology database. A questionnaire evaluated the reasons for block reclaiming by the peripheral pathologists.

RESULTS

There is a significant increase in block reclaims during the period analyzed among submissions for consultation as well as in clinical trials (linear regression, p = 0.0195 and p = 0.0107). The percentage of block reclaims does not differ between consultations and cases submitted upon request within clinical trials (p = 0.2404, t-test). A survey among pathologies that reclaim the block showed that their willingness to leave the block at the reference center would increase if the compatibility with accreditation guidelines (39.3%), a positive statement from professional associations (25%), or a formal confirmation of availability (53.6%) is provided.

DISCUSSION

In particular, to improve research on rare diseases, it is desirable to point out the compatibility of central archiving in a designated center with accreditation guidelines.