Just because something isn’t named explicitly, doesn’t mean we cannot identify it. All it takes is reading between the lines, taking the indirect evidence that we do have, and drawing logical conclusions from it. Back in 2012 I was researching Lodewijk Wesselo, one of my great-uncles. It was then that I first had a conclusion that completely relied on indirect evidence.
During the early 1940s Lodewijk Wesselo had an illness. There’s no medical information available for this, merely mentions he makes himself in various letters written in 1944. And in those letters, he doesn’t explicitly states what illness he has. All I had were fragmentary comments that describe symptoms and sometimes treatments.
A. “Maandag voor 8 dagen voor het laatst bestraald vermoedelijk eind dezer maand naar Adam voor onderzoek en dan gaan praten. alsnog maar fluisteren” 
(Translation: Monday radiation therapy for 8 days for the last time, probably to Amsterdam at the end of the month for examination and then starting to talk. For now, just whispering.)
B. “30 sept was ik voor controle bij de Radio Dr.. die een klein zweertje ontdekte op de oude geschiedenis, hij achte het nodig dat ik Dr. N daarvan in kennis stelde, die kwam tot dezelfde conclusie maar zei erbij dat hij voor onderzoek een stukje moest weg knippen anders geen zekerheid kan hebben wat het was. Ik heb een paar nare dagen gehad vooral door de vedoving en het binnenkrijgen van het middel. Zelf heb ik het flesje naar het Pathologis Inst. gebracht – en mocht ik van Dr. N. Donderdag vernemen dat het onschuldig was. eind dezer maand weer bij 2 terugkomen. Mijn stem, ik begon al zo aardig te babbelen, is weer geheel weg en moet van meet af aan beginnen. spraakles stop gezet.” 
(Translation: 30 September I was with the radiologist for a check-up, who found a small spot. Knowing the old history, he found it necessary that I notify Dr. N., who came to the same conclusion and said he would have to cut off a piece of it for examination or there was no certainty about what it was. I’ve had a few bad days because of the anesthesia and the ingesting of the fluid. Have taken the bottle to the pathological institute myself, and was notified by Dr. N. on Thursday that it was harmless. End of the month I have to see him again. My voice, I had begun to talk pretty well again, is completely gone again and I have to start all over again. I’ve stopped the speech lessons.)
C: “Met mij gaat het heel goed. Wat ten kwade leek heeft God ten goede gekeerd, de oude wond is prachtig en de Heren waren zeer tevreden, ik heb dus geen spijt van die laatste uitknipperij, ga volgende week weer spreekles nemen, ik hoop straks nog mee te kunnen zingen al is het maar een klein versje.” 
(Translation: I am doing well. What seemed evil, God has turned to good, the old wound has healed magnificently and the Lord was pleased. I do not regret the last surgery. Next week I will start speech lessons again, I hope to be able to sing along, even if it is only a small verse.)
D. “Zaterdag was ik bij de Spec. en die kon mij genezen verklaren, je begrijpt hoe dankbaar wij zijn met dit heerlijke geschenk. Mijn stem is niet mooi maar aan verbetering wordt niet getwijfelt.” 
(Translation: I was at the specialist on Saturday and he could call me cured. You understand how thankful we are for this wonderful gift. My voice is not pretty, but there is no doubt it will improve.)
When quote A is made, the illness is clearly nearing its end. Lodewijk talks about having his last radiation therapy. Radiation therapy is a standard treatment for cancer these days. It’s been used as a treatment sinds 1902, though radiation treatment of only the part of the body that was affected has been used since the 1920s.  In 1913, the Netherlands Cancer Institute is founded and in 1938, the new policlinic and radiology department is opened. From the letter it is not clear if the radiation therapy itself was in Amsterdam, but considering Lodwijk is also seeing a specialist in Amsterdam, it is likely he was going to the Netherlands Cancer Institute for treatment.
Lodewijk also mentions he’s whispering in quote A. Quote B & C clearly indicate that this condition came through surgery on the throat area. Quote B tells us the most, namely that there is some kind of ‘spot’ on the throat, and that a biopsy is needed to see if it is evil (see quote C) or in other words malignant – due to “old history”. Quote D tells us he is now cured – good news for Lodewijk – and that he was seeing a specialist.
The surgery, radiation therapy, the biopsy on a spot on his throat, the waiting for news on whether it’s malignant or not, the specialist in Amsterdam, it all points to cancer. Throat cancer, to be exact. It’s never explicitly named that, but all the information together makes me pretty confident in calling it that.
This post is an rewrite of a blog post previously published on my former blog Tracing My Roots. It was adapted and updated from the original version that was titled ‘Indirect Evidence for an Illness’ posted on 9 November 2012.
 Handwritten postcard from Lo [Lodewijk Wesselo] to Bram [Abraham Wesselo, his brother], 4 September 1944, portfolio 3, doos 1, familiearchief Wesselo, Familiearchieven: CBG, fa 00472, CBG, Den Haag.
 Handwritten postcard from E. Ant Lo [Elisabeth Lubach (Lodewijk’s wife), Antje Wesselo (Lodewijks daughter) and Lodewijk Wesselo] to Bram x Riek [Abraham Wesselo, and his wife Hendrika Johanna Wilhelmina Broer, his brother and sister-in-law], 10 October 1944, portfolio 3, doos 1, familiearchief Wesselo, Familiearchieven: CBG, fa 00472, CBG, Den Haag.
 Handwritten postcard from E. Ant & Lo [Elisabeth Lubach (Lodewijk’s wife), Antje Wesselo (Lodewijks daughter) and Lodewijk Wesselo] to Bram & Riek [Abraham Wesselo, and his wife Hendrika Johanna Wilhelmina Broer, his brother and sister-in-law], 29 October 1944, portfolio 3, doos 1, familiearchief Wesselo, Familiearchieven: CBG, fa 00472, CBG, Den Haag.
 Handwritten postcard from E. A. L. [Elisabeth Lubach (Lodewijk’s wife), Antje Wesselo (Lodewijks daughter) and Lodewijk Wesselo] to Bram & Riek [Abraham Wesselo, and his wife Hendrika Johanna Wilhelmina Broer, his brother and sister-in-law], 25 December 1944, portfolio 3, doos 1, familiearchief Wesselo, Familiearchieven: CBG, fa 00472, CBG, Den Haag.
 “Geschiedenis van de behandeling” page, Behandeling tab, Beter (http://beternahodgkin.nl/behandeling/geschiedenis-van-de-radiotherapie : accessed 5 January 2019).
 “Radiotherapie tijdlijn”, 100 jaar radiotherapie (https://www.historad.com/nl/#! : accessed 5 January 2019).