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dimensions could be set—[Y (height of the block) = 22 mm; X

(width of the block) = 28 mm; X spots (number of columns) = 10;

Y spots (number of rows) = 8; total spots = 80; X-margin (distance

of tissue array from the nearest X margin) = 4 mm; Y-margin (dis-

tance of tissue array from the nearest Y margin) = 3 mm; needle

diameter = 1.5 mm; S (spacing between two tissue spots) = 0.5 mm

and P (pitch—distance between center of one tissue and center of

adjacent tissue) = 2 mm].

We need to design the order of the “donor” blocks that are going

to put into the tissue microarray. In this phase, the “donor” blocks

to be used are defined and associated with one or more TMA spots.

Define the “donor” blocks selected for the array in the “donor”

block(s) tab in the program. “Donor” blocks can be defined one

by one or together.

●● Start up the program in the machine.

●● Following the software instructions, the next step is inserting

the empty “recipient” block into the block holder. The block

surface should be identical to the base plate.

●● Place the “donor” blocks in their holder.

●● Start construction button and the punching needle will move

to the position of the “recipient” block as designed by the

template.

●● Manually use the needle to create a hole in the first position of

the array configuration starts the arraying process. The smaller

punch is used to create the hole. The depth should be half of

“recipient” block thickness a great length is 0.5–1 mm above

the plastic block holder surface. Push the punch down, as an

appropriate depth, by hand (Fig. 2c).

●● Use the handle in the punch to turn the punch around 45°.

This twisting movement helps release the paraffin core from

the block.

●● Pull the needle up.

●● Then, the program will turn the larger needle to the spot to

cut the tissue from the “donor” block.

●● Manually insert the needle into the “donor” block (Fig. 2d).

●● Pull the needle up (tissue sample in the needle).

●● The program will turn the needle (with the tissue sample) to

the designed spot in the “recipient’ block.

●● Manually insert the needle with tissue in the designed spot into

the “recipient” block.

●● Pull the needle up.

3.2.3 TMA Design

3.2.4 Construction

TMA and Esophageal Adenocarcinoma