HITHOC: the Indian experience

This 2019 article from the Indian Journal of Surgical Oncology covers a very tiny group of patients undergoing HITHOC during an 8 1/2 year period has serious limitations (with a total of only seven patients having HITHOC) but it’s still worth a few minutes of our readers time, particularly if the reader’s interest in HITHOC hasn’t translated into practice yet.

Patel et. al.  do a very nice job of describing their inclusion criteria, as well as the surgical techniques utilized in this study, where patients underwent either pleurectomy/ decortication (P/D) or extrapleural pneumonectomy (EPP) with/ without HITHOC.

In fact, it’s one of the better overviews of the procedure that’s been published in recent years.  This praise must be tempered by the fact that HITHOC is paired with two very high morbidity/ mortality procedures in this study.  P/D and EPP alone are difficult-to-tolerate procedures, and for that reason, are limited to a small subset of eligible patients.  Multiple studies by the leaders in the area of HITHOC such as Reid, Isik etc.  have already demonstrated that HITHOC can be effective without EPP.

For readers, there are some other serious limitations in their study.  Despite having a tiny sample size, the HITHOC and non-HITHOC groups are not comparable.  It is figuratively; apples to oranges.  

The non-HITHOC group was primarily made up of pleural mesothelioma patients, and based on that diagnosis alone – would have been expected to do worse post-operatively.  Yet, we don’t know if they did (do worse or not).

One of the reasons that we don’t know if the pleural mesothelioma patients outlived the HITHOC treatment group is that measurements were discordant as well.  The authors talk about 24 month and 36 month survival in the non-HITHOC group, but apparently, didn’t even follow the HITHOC group after 9 months. (Or chose not to present their data after nine months, which is, worse. )

The authors do acknowledge this, in their discussion, but also point out that two of the HITHOC patients (one a 40 year old female*) had extensive, infiltrating disease processes and poor pre-operative functional statuses.

It’s an interesting read for the most part, but it begs for follow-up so we will reach out to Patel etl. al. and update readers with any response.

Reference article

Patel MD, Damodaran D, Rangole A, et al. (2019). Hyperthermic Intrathoracic Chemotherapy (HITHOC) for Pleural Malignancies-Experience from Indian CentersIndian J Surg Oncol. 2019;10(Suppl 1):91–98. doi:10.1007/s13193-018-0859-y  [link to free full text].

*There are two charts that nicely display all the characteristics of patients in both groups. Interestingly, in this HITHOC group, both of the female patients presented with more advanced disease many, many months after initial diagnosis.  The 40F patient is clearly a last ditch ‘salvage’ patient, so her six month survival time after surgery would be better measured against more palliative procedures.